Balance spring stud holder device

Abstract

To provide a balance-spring stud holder capable of accurately positioning a balance spring stud.SOLUTION: A balance-spring stud holder 2 includes a clamping portion 12 forming three contact areas 18, 20, 22 intended to press against the side walls of the projecting portion of the balance bridge. A first contact region 18 is connected to a second contact region 20 via a first portion 24 and to the second contact region 20 via a second portion 26 of the clamping portion 12. The first portion 24 has a first stiffness at a second midpoint 30 of the second contact region 20 relative to a first midpoint of the first contact region 18, and the first stiffness is greater than three times a second stiffness that the second portion 26 has at a third midpoint 32 of the third contact region 22 relative to the first midpoint of the first contact region 18. The first stiffness is preferably 7 times the second stiffness, and preferably 12 times the second stiffness.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a balance spring stud holder device mounted on a movement for a timepiece, and more precisely, disposed on a balance bridge.

Background Art

[0002] According to French Patent Document FR2368070, a balance spring stud holder device is known. This balance spring stud holder device is attached by friction to a shoulder (a protruding cylindrical part) on the balance bridge or to a support of an impact-resistant bearing provided for balancing. This balance spring stud holder comprises an annular split ring having two symmetrical arms with a specific elasticity, thereby enabling the friction attachment of the balance spring stud holder onto the balance bridge. The inner circle of the split ring is designed to have a diameter slightly smaller than the diameter of the annular part of the protrusion or the support of the impact-resistant bearing intended to receive the balance spring stud holder, whereby the two elastic arms are slightly separated during assembly to provide a specific amount of clamping and obtain the required friction. Thus, the inner circle has a diameter smaller than the part to be attached, and for this reason, during assembly, the balance spring stud holder makes a small movement along the axis passing through the center of said circle and the center of the gap between the elastic arms, in a direction opposite to this gap from said center. Generally, as shown in this document, the part of the balance spring stud holder to which the balance spring stud is attached is located on said axis on the side opposite to the gap of the split ring. Therefore, after the balance spring stud holder is attached to the balance bridge, the distance between the axis of the balance spring stud and the center of the inner circle of the split ring changes. In fact, this distance increases, which causes a problem in the accuracy of the point where the balance spring is attached to the balance bridge. It should be noted that this problem occurs regardless of the angular position of the part to which the balance spring stud is attached with respect to the center of the split ring. This is because in all cases, this part to which the balance spring is attached makes a translational movement along the axis passing through the center of the gap and the part of the split ring on the diametrically opposite side of the gap when the balance spring stud holder is frictionally attached to the balance bridge.

[0003] Swiss Patent Document CH604226 discloses a balance spring stud holder which is bayonet - mounted on one part of a balance bridge and is configured to be held in a predetermined angular position by the friction of a ring which forms a balance spring stud holder on this part. In particular, the part of the balance bridge of concern is a component which is housed within a hole formed in the plate of the balance bridge and projects above this plate. This component is configured to receive the balance bearing. The ring has an inner flat part which clamps the side wall of said component at three points after rotating the balance spring stud holder to close the bayonet system, thereby maintaining the angular positioning by the friction of the ring. During rotation during clamping, the flat part in the ring moves with respect to the initial center of this ring, thereby causing the same problem as the problem previously highlighted in French Patent Document FR2368070. This is because the area where the balance spring stud is attached moves slightly within the plane of the balance spring stud holder about the central axis of the housed component which defines the axis of rotation of the balance during the rotation of the balance spring stud holder, in order to close the bayonet system and enable clamping.

[0004] In addition, European Patent Document EP1798609 also discloses a balance spring stud holder that forms a bayonet system with a protrusion of a balance bridge, as shown in FIG. 2 of this document. This balance spring stud holder is distinguished by three protrusions that form a bayonet system, and these three protrusions are located inside a ring that surrounds the protrusion. These three protrusions contribute to the bayonet system by enabling, in a first step, the balance spring stud holder to be freely attached at the correct level around the protrusion and then inserted by rotation of the balance spring stud holder in three corresponding lateral grooves formed in the protrusion, thereby closing the bayonet system. In order to prevent the balance spring stud holder from having a clearance with respect to the protrusion, a firm friction is generated. However, nothing is taught about the elasticity of the two parts of the balance spring stud holder between the central protrusion and the two end protrusions with a gap therebetween. In fact, the elasticity of these two parts may be small, and the friction generated may also be small. This is because the friction only serves to prevent clearance and does not serve for the axial retention of the balance spring stud holder obtained by the bayonet system, nor for the angular positioning of the balance spring stud holder. This is because this angular positioning is achieved by a swan neck return spring and a micrometric screw. It should be noted that from the teaching given in European Patent Document EP1798609, it is not possible to think or conclude that one of the two parts of the balance spring stud holder surrounding the protruding part has a different elasticity from the other part. Summary of the Invention Problems to be Solved by the Invention

[0005] An object of the present invention is to provide a balance spring stud holder that does not have the disadvantages of the conventional balance spring stud holder described above. In particular, the present invention aims to provide a balance spring stud holder that enables very accurate positioning of the balance spring stud in the general plane of the balance spring stud holder, in particular, very accurate and predetermined radial positioning with respect to the rotation axis of the balance spring.

Means for Solving the Problems

[0006] For this purpose, the present invention relates to a balance spring stud holder intended to be attached to a balance bridge of a mechanical movement of a timepiece, the balance spring stud holder having an attachment portion for attaching a balance spring stud and a clamping portion designed to be able to clamp a side wall of a protruding portion of the balance bridge or a side wall of a component attached to the balance bridge. The clamping portion forms three contact regions, and the three contact regions are intended to press against the side wall of the protruding portion or the component after the balance spring stud holder is attached to the balance bridge. A first contact region of the three contact regions is connected to a second contact region of the three contact regions, and the second contact region is adjacent to the first contact region via a first portion of the clamping portion. There is a first separation region between the first and second contact regions in the first portion. The first contact region is also connected to a third contact region of the three contact regions, and the third contact region is also adjacent to the first contact region via a second portion of the clamping portion having a second separation region between the first contact region and the third contact region. The first and second separation regions are provided so as to retreat from the side wall of the protruding portion or the component after the balance spring stud holder is attached to the balance bridge. In a general plane in which the entire clamping portion extends, the first portion has a first rigidity at a second central point of the second contact region with respect to a first central point of the first contact region, and the first rigidity is greater than three times a second rigidity that the second portion has at a third central point of the third contact region with respect to the first central point of the first contact region.

[0007] In a preferred variant, the first rigidity is greater than seven times the second rigidity. In a preferred variant, the first rigidity is greater than twelve times the second rigidity.

[0008] In a main embodiment, in the general plane, the first portion is a rigid body and the second portion is an elastic body.

[0009] In order to clearly characterize the rigidity of the first part and the second part, an object of the present invention is, as described above, characterized by the relative values of the rigidity of these first parts and second parts in the three mutant forms under consideration. In this way, potential problems related to the clarity of the terms "rigidity" and "elasticity" are solved. However, in the main embodiment, it can be said that in the general plane, the first part has rigidity (hardly deforms), and the second part has elasticity / flexibility. This is because when the balance spring stud holder is attached to the balance bridge, the higher the rigidity of the first part, that is, the less it deforms substantially, the more precise the centering of the balance spring stud holder provided by the present invention becomes, and therefore, the more precise the radial position of the balance spring stud becomes.

[0010] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that this description is given as an example and is not limited thereto.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying out the Invention

[0012] Hereinafter, with reference to Figures 1A, 1B and 2A, 2B, two modified forms of the first embodiment of the balance spring stud holder according to the present invention will be described.

[0013] Figure 1A shows the balance spring stud holder 2 according to the first modified form before being attached to the balance bridge, and Figure 1B shows the balance spring stud holder 2 after being attached to the balance bridge 4. The balance bridge 4 is provided in a mechanical timepiece movement with a balance spring in a traditional form, and the balance of this balance spring rotates within a bearing (these elements are not shown). This bearing is provided at the center of the protrusion 6 of the balance bridge or the center of a component attached to this balance bridge, and the outer end of the balance spring is held by a balance spring stud 9, and this balance spring stud 9 is attached in a known form, particularly by a lateral screw, within an opening 8 in the attachment portion 10 of the balance spring stud holder. Instead of this opening, particularly a groove can be used, and those skilled in the art can contemplate various modified forms for attaching the balance spring stud to the balance spring stud holder.

[0014] The balance spring stud holder has a clamping part 12 which is designed to be able to clamp the side wall 16 of the protruding part 6 or, in one variant form, the side wall of a part attached to this balance bridge. The protruding part or the part has a cylindrical or slightly inclined frustoconical part, the outer surface of which cylindrical or frustoconical shape forms the side wall 16, and the central axis 14 forms the axis of rotation of the balance. The part is, in particular, a part of a regulator assembly comprising the balance spring stud holder of interest or a bearing support provided for the balance spring. When the balance spring stud holder 2 is attached to the frustoconical part, the annular cross-section of this part increases as it moves away from the plate 5 of the balance bridge 4. The expression "attached" does not necessarily mean that the part is on top of the plate of the balance bridge with respect to the space provided for the balance spring. This is because in some embodiments, the balance spring stud holder can be arranged under the plate of the balance bridge on the balance spring side.

[0015] The clamping part 12 forms three contact areas 18, 20 and 22 which are intended to press against the side wall 16 of the protruding part 6 or the part after the balance spring stud holder is attached to the balance bridge. The first contact area 18 of the three contact areas is connected to the second contact area 20 of the three contact areas adjacent to the first contact area 18 via a first part 24 of the clamping part 12. There is a first separation area 25 between the first contact area 18 and the second contact area 20 in this first part 24. Also, the first contact area 18 is similarly connected to the third contact area 22 of the three contact areas adjacent to the first contact area 18 via a second part 26 of the clamping part 12. There is a second separation area 27 between the first contact area 18 and the third contact area 22 in this second part 26. After the balance spring stud holder 2 is attached to the balance bridge 4, the first and second separation areas 25 and 27 are provided so as to be recessed from the side wall 16 of the protruding part or the part.

[0016] In a general variant form, the first contact region 18 and the second contact region 20 each contact a geometric circle 17 at a first central point 28 of the first contact region and a second central point 30 of the second contact region in a general plane in which the entire clamping portion 12 extends. In this general variant form, the ranges of the first and second contact regions are each determined by the first and second contact points with respect to the geometric circle 17 that contacts the first and second contact regions at the first and second contact points that form the first and second central points.

[0017] In the various illustrated embodiments, the three contact regions are flat. Preferably, at least the first and second contact regions 18, 20 are flat, and in a general plane in which the entire clamping portion extends, two radii passing through the first and second central points 28, 30 centered on the center 15 of the geometric circle 17 are orthogonal. Other variant forms are also possible. In a specific variant form, the first and second contact regions are concave so as to describe an arc of a circle having the same radius and the same center as the geometric circle 17. In another specific variant form, these contact regions are slightly convex with respect to, for example, an arc of a circle having the same radius as the radius of the geometric circle.

[0018] In the first variant form of FIGS. 1A and 1B, the first portion 24 forms a first annular arm having a rectangular cross-section with a width L1 and an average radius R1 from the center 15 of the geometric circle 17 in the first separation region 25. The first separation region 25 extends over a first angular distance φ. The second portion 26 forms a second annular arm having a rectangular cross-section with a width L2 and an average radius R2 from the center 15 of the geometric circle 17 in the second separation region 27. The second separation region 27 extends over a second angular distance θ.

[0019] According to the present invention, in the general plane in which the entire clamping portion 12 extends, the first portion 24 has a first rigidity K1 at the second central point 30 of the second contact region 20 with respect to the first central point 28 of the first contact region 18, and the first rigidity K1 is greater than three times the second rigidity K2 that the second portion 26 has at the third central point 32 of the third contact region 22 with respect to the first central point 28 of the first contact region. That is, K1 > 3·K2. Note that the rigidity is the flexural rigidity, and the elastic constants of the first portion and the second portion are determined by the reciprocals of their flexural rigidities, respectively.

[0020] In one preferred variant, the first rigidity K1 is greater than seven times the second rigidity K2. That is, K1 > 7·K2.

[0021] In a preferred variant, the first rigidity K1 is greater than twelve times the second rigidity K2. That is, K1 > 12·K2.

[0022] In the example shown in FIGS. 1A and 1B, the width L2 = 0.55·L1, the first angle φ = 68°, and the second angle θ = 110°. According to the laws of physics, the flexural rigidity K varies according to the cube of the width L of the portion of interest (here, the annular arm). That is, K~L 3 and also varies according to the cube of its length. That is, K~(R·ψ) 3 where R is the average radius of the annular arm and ψ is the angular distance of this annular arm. Considering only the two annular arms located in the two separation regions 25 and 27 as a first approximation, K1 = K2·(1.5) 3 ·(1.8) 3 is obtained, that is, approximately K1 = 20·K2. Therefore, the first rigidity K1 is approximately 20 times greater than the second rigidity K2. Therefore, in this example, the elasticity of the second portion 26, specifically the second separation region 27, is approximately 20 times greater than the elasticity of the first portion 24, specifically the first separation region 25.

[0023] In two variants of the first embodiment, the third central point 32 of the third contact region 22 is substantially on the straight line 34 that bisects the first angle α formed between the first and second central points 28 and 30 about the center 15 of the geometric circle 17 that contacts the first and second contact regions 18 and 20 in the general plane in which the entire clamp portion 12 extends. The adverb "substantially" means, in particular, that the situation may be before or after attaching the balance spring stud 2 to the balance bridge 4. In the first variant, the first angle α is substantially 90°, and then the third central point 32 has a second angle β with respect to the first central point 28 about the center 15 of the geometric circle 17, and this second angle β is substantially 135°.

[0024] Thanks to the properties of the balance spring stud holder 2 according to the present invention, it is possible to attach the balance spring stud holder to the projection 6 of the balance bridge while ensuring extremely accurate radial positioning of the opening 8, and thus of the balance spring stud 9, with respect to the central axis 14 of the projection that coincides with the vibration axis of the balance spring. Also, the accurate positioning in the general plane of the balance spring stud holder perpendicular to the axis of rotation 14 of the balance is preferably obtained using two contact areas 18 and 20 that are angularly offset by an angle of 60 to 120°, preferably 90°. This is because the rigidity in the first part 24 connecting the two contact areas 18, 20 is greater than that of the second part 26 connecting the two contact areas 18, 22. This second part 26 has essentially only the contact area 22 with sufficient elasticity to allow movement of the balance spring stud holder in the general plane with respect to the contact area 18 during the separation between the two parts 24, 26. Thus, the following can be said about the first rigid part 24 and the second elastic part 26. Before the balance spring stud holder is attached to the balance bridge, the contact area 22 is inside the geometric circle 17 that touches the two contact areas 18 and 20. Thus, on the premise that the attachment part 10 of the balance spring stud is firmly connected to the first rigid part of the clamp part 12, during attachment, substantially only the second elastic part undergoes elastic deformation, and after the balance spring stud holder is angularly positioned on the projection 6, it is the first and second contact areas 18 and 20 that provide the accurate radial positioning of the balance spring stud 9 and the accurate positioning in the general plane of the balance spring stud holder. This is because considering that the radius of the geometric circle 17 in contact with the contact areas 18 and 20 is made equal to the radius of the projection 6 in the general plane of interest within the tolerance range of the machining of the balance spring stud holder and the projection and the tolerance range that can be made as small as possible by those skilled in the art for the machining techniques that can be used, since the first part 24 is rigid, after the balance spring stud holder is attached to the balance bridge, the center 15 of the geometric circle 17 is on the central axis 14 of the projection 6.

[0025] The balance spring stud holder 2 further has a free portion 36 that extends the first portion 24 beyond the second contact region 20. This free portion 36 has several functions. In particular, a safety function for preventing the balance spring stud holder from moving laterally due to impact, a mounting function for allowing a specific tool to temporarily move the third contact region 22 away from the center 15, and an aesthetic function.

[0026] Figures 2A and 2B relate to a second variant of a first embodiment that is essentially different from the first variant in that the first angle α and the second angle β are equal and each is 120 degrees (120°). In this case, the first angle φ (also called the first angular distance) is substantially equal to the second angle θ (also called the second angular distance). Various parts of the balance spring stud holder 42, including a clamp portion 12A having a first portion 24A that connects the contact regions 18 and 20 to form a first separation region 25A and a second portion 26A that connects the contact regions 18 and 22 to form a second separation region 27A, will not be described in detail again. It can be observed that the balance spring stud holder 42 does not include an additional free portion.

[0027] Based on the example shown in Figures 2A and 2B, the following results are obtained. That is, the first stiffness K1 of the first portion 24A, specifically the first separation region 25A, is approximately 5 times the second stiffness K2 of the second portion 26A, specifically the second separation region 27A. Therefore, in this example, the elasticity of the second portion 26A, specifically the second separation region 27A, is approximately 5 times greater than the elasticity of the first portion 24A, specifically the first separation region 25A. Note that this value changes significantly only when the ratio of the width L1 to the width L2 changes relatively little. Generally, the ratio of the first stiffness K1 to the second stiffness K2 is greater than 3. Preferably, this ratio is greater than 7 and can be easily obtained in the second variant. Preferably, the ratio K1 / K2 is greater than 12.

[0028] Figures 3A and 3B show a second embodiment of the balance spring stud holder according to the present invention. Parts of the balance spring stud holder 52 that are the same as or similar to those of the first embodiment already described will not be described in detail again. Therefore, for these same or similar parts, reference should be made to the description of the first embodiment. Note that the letter "B" added to the reference numerals indicates that the parts with these reference numerals are the same as the parts with the same reference numerals as the reference numerals in the first embodiment.

[0029] The balance spring stud holder 52 includes an attachment portion 10 for the balance spring stud 9, and this attachment portion 10 is fixed to the first part 24 of the clamp portion 12B. In particular, the attachment portion 10 is rigid and firmly attached to the first part 24. "Firmly attached" does not mean that these two parts must be initially separate parts attached to each other, but rather means that the attachment portion and the first part form the rigid parts of the balance spring stud holder together, and this rigid portion forms first and second contact regions 18, 20 with a separation region therebetween over a specific non-zero angular distance, preferably 60 to 120°, preferably substantially 90°. The clamp portion 12B further has a second part 26B that connects the first contact region 18 to the third contact region 22. Also, the clamp portion 12B forms a fourth contact region 56 intended to press against the side wall 16 of the protrusion 6 of the balance bridge (not shown) or the side wall of the portion attached to this balance bridge after the balance spring stud holder 52 is attached to the balance bridge. This fourth contact region 56 is adjacent to the second contact region 20 and is connected to this second contact region 20 via a third part 54 of the clamp portion 12B having a third separation region 55 between the second contact region and the fourth contact region. The third part 54 has a third stiffness K3 at the fourth central point 58 of the fourth contact region with respect to the second central point 30 of the second contact region, and this third stiffness K3 is less than one-third of the first stiffness K1 of the first part 24. In a preferred variant, the first stiffness K1 is greater than seven times the third stiffness K3. That is, K1 > 7·K3. Thus, like the second part, the third part 54 is elastic.

[0030] Thanks to the double configuration of the second and third elastic parts, the total clamping force of the balance spring stud holder on the protrusion 6 increases. The value of the width L2 of the separation region defined by the second and third parts 26B and 54 can be selected to determine the elasticity of these two parts. Similar to the third contact region 22, the fourth contact region 56 is arranged inside the geometric circle 17 that contacts the first and second contact regions 18 and 20 at their central points before the balance spring stud holder is attached to the balance bridge. To determine the total clamping force, the radial distances of the contact regions 22 and 56 for the balance spring stud holder not attached to the balance bridge can also be selected.

[0031] In the illustrated variant, the third and fourth contact regions 22, 56 have axial symmetry with respect to a straight line 34 that bisects a first angle α formed by an angle corresponding to the offset between the first contact region 18 and the second contact region 20 about the center 15 of the geometric circle 17 in the general plane of the clamp part 12B. In particular, the second part 26B and the third part 54 are arranged symmetrically with respect to the bisecting straight line 34 such that the angular distance θ1 of the second separation region 27B is equal to the angular distance θ2 of the third separation region 55 defined by the third part 54. Therefore, the second part 26B and the third part 54 of the clamp part 12B have axial symmetry with respect to the bisecting straight line 34.

[0032] At the free ends of the second and third parts 26B and 54, there are two radially extending parts 62 and 64 respectively, and these two parts 62 and 64 are provided to facilitate attaching the balance spring stud holder 52 around the protrusion 6 of the balance bridge using a tool 66.

[0033] Figures 4A and 4B show a third embodiment of the present invention. The balance spring stud holder 72 has a much more complex shape than the balance spring stud holders shown in other figures. This balance spring stud holder 72 serves several functions, which accounts for its particular shape. The balance spring stud holder 72 has an attachment portion 10C provided for attaching the balance spring stud 9 and a clamp portion 12C that generally forms an open ring. Similar to the embodiments described previously, the clamp portion or open ring does not have uniform elasticity or does not have elasticity over substantially the entire angular range but has elasticity due to the presence of at least one elastic portion. The clamp portion 12C has a first rigid portion 24C connecting the first and second contact regions 18 and 20 and a second elastic portion 26C connecting the first and second contact regions 18 and 22. The first and second contact regions 18 and 20 each form an angle α between their corresponding central points, and the first and third contact regions each form an angle β between their corresponding central points, and this angle β is substantially equal to the angle α in the illustrated example. Note that the angles α and β have values greater than 120° and approximately 150°. Therefore, this variant is not preferable considering the advantages of the present invention. However, since the first rigid component 24C has a much higher rigidity, particularly greater than 12 times, than the rigidity of the second elastic component 26C, due to the angle α being greater than 120° and 150°, after the balance spring stud 9 is attached to a balance bridge (not shown), in the general plane of the balance spring stud holder, the attachment portion 10C firmly coupled to the first portion 24C, and thus the accurate positioning of the balance spring stud 9, becomes possible.

[0034] The first portion 24C has a minimum width L1 at a single point Min and the second portion 26C is less than L1 Min and substantially L1 MinIt has an annular arm having a width L2 that is two-thirds of , and this annular arm extends over an angle Ω greater than 60°. Thus, when the balance spring stud holder 72 is attached around the protrusion 6 of the balance bridge, substantially only the second part 26C elastically deforms. This attachment is performed using a tool 66 that allows insertion into the gap between the first and second parts of the clamp part 12C to separate the free ends from each other.

Explanation of Signs

[0035] 2, 42, 52, 72 Balance spring stud holder 10 Attachment part 12, 12A, 12B, 12C Clamp part 15 Center of the geometric circle 17 Geometric circle 18 First contact area 20 Second contact area 22 Third contact area 24, 24A, 24C First part of the clamp part 25, 25A First separation area 26, 26A, 26B, 26C Second part of the clamp part 27, 27A, 27B Second separation area 28 First central point 30 Second central point 32 Third central point 34 Straight line 54 Third part 55 Third separation area 56 Fourth contact area 58 Fourth central point

Claims

1. A balance spring stud holder (2, 42, 52, 72) intended to be attached to a balance bridge of a mechanical movement of a timer, wherein the balance spring stud holder has an attachment portion (10) for attaching a balance spring stud, and a clamping portion (12, 12A, 12B, 12C) designed to be able to clamp a side wall of a protruding portion of the balance bridge or a side wall of a component attached to the balance bridge, the clamping portion forms three contact regions (18, 20, 22), the three contact regions (18, 20, 22) are intended to press against the side wall of the protruding portion or the component after the balance spring stud holder is attached to the balance bridge, a first contact region (18) among the three contact regions is connected to a second contact region (20) among the three contact regions, the second contact region (20) is adjacent to the first contact region via a first part (24, 24A, 24C) of the clamping portion, a first separation region (25, 25A) exists between the first and second contact regions in the first part (24, 24A, 24C), the first contact region (18) is also connected to a third contact region (22) among the three contact regions, the third contact region (22) is also adjacent to the first contact region via a second part (26, 26A, 26B, 26C) of the clamping portion having a second separation region (27, 27A, 27B) between the first contact region and the third contact region, the first and second separation regions are provided so as to retreat from the side wall of the protruding portion or the component after the balance spring stud holder is attached to the balance bridge, in a general plane in which the entire clamping portion extends, the first part has a first rigidity at a second central point (30) of the second contact region (20) with respect to a first central point (28) of the first contact region (18), the first rigidity is greater than three times a second rigidity that the second part has at a third central point (32) of the third contact region (22) with respect to the first central point of the first contact region, characterized in that it is a balance spring stud holder.

2. The first rigidity is greater than seven times the second rigidity. The balance spring stud holder according to claim 1, characterized in that...

3. The first rigidity is greater than 12 times the second rigidity The balance spring stud holder according to claim 1, characterized in that...

4. In the general plane, the first part is a rigid body and the second part is an elastic body The balance spring stud holder according to claim 1, characterized in that...

5. The third central point (32) of the third contact region is on a straight line (34) that bisects a first angle (α) formed between the first and second central points about the center (15) of a geometric circle (17) that contacts the first and second contact regions in the general plane in which the entire clamp portion extends, and the first and second contact regions are formed to partially coincide with arcs of a circle having the same radius and the same center as the geometric circle The balance spring stud holder according to any one of claims 1 to 4, characterized in that...

6. The first angle (α) is 90°, The third central point (32) is such that a second angle (β) formed between it and the first central point about the center (15) of the geometric circle is 135° The balance spring stud holder according to claim 5, characterized in that...

7. The first angle (α) is 120°, The third central point (32) is such that a second angle (β) formed between it and the first central point about the center (15) of the geometric circle is 120° The balance spring stud holder according to claim 5, characterized in that...

8. The clamp portion (12B) forms a fourth contact region (56) intended to press against the side wall of the protrusion or component after the balance spring stud holder is attached to the balance bridge, The fourth contact region is adjacent to the second contact region (20) and is connected to the second contact region via a third portion (54) of the clamp portion, There is a third separation region (55) between the second and fourth contact regions in the third portion (54), The third portion has a third rigidity that is less than one-third of the first rigidity of the first part at the fourth central point (58) of the fourth contact region with respect to the second central point (30) of the second contact region The balance spring stud holder according to claim 1, characterized in that...

9. The first rigidity is greater than seven times the second rigidity and greater than seven times the third rigidity. The balance spring stud holder according to claim 8, characterized in that.

10. The third and fourth contact regions (22, 56) are centered on the center (15) of the geometric circle (17) in the general plane in which the entire clamping portion extends and are in contact with the first and second contact regions. It has axial symmetry with respect to a straight line (34) that bisects a first angle (α) formed between a first central point of the first contact region and a second central point of the second contact region, and the first and second contact regions are formed so as to partially coincide with an arc of a circle having the same radius and the same center as the geometric circle. The balance spring stud holder according to claim 8 or 9, characterized in that.

11. The second part (26B) and the third part (54) of the clamping portion have axial symmetry with respect to the straight line (34). The balance spring stud holder according to claim 10, characterized in that.

12. The first and second contact regions (18, 20) are flat. The balance spring stud holder according to claim 1, characterized in that.

13. The first and second contact regions (18, 20) are flat. The balance spring stud holder according to claim 5, characterized in that.

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