EP2781967A1 - Timepiece hairspring - Google Patents

Abstract

The sub-assembly (1) has a bridge (3), and a balance spring (71) whose outer end is secured to a balance spring stud (73). The balance spring and the spring stud are connected to form a single-piece assembly with the bridge. The spring stud is designed in a position-adjustable manner and locked in a pre-adjusted position by a locking unit. The spring stud is fixed to the bridge by an elastic return unit, where the balance spring comprises an outer coil (77) that is clamped by two pins. One of the pins is secured to the bridge by the return unit.

Description

Field of the invention

The invention relates to a watch exhaust mechanism subassembly comprising at least one bridge and at least one spiral spring whose outer end is fixed to a pin.

The invention also relates to a mechanical clockwork movement comprising at least one such subassembly.

The invention relates to the field of watch mechanisms, and more particularly exhaust mechanisms incorporating ready-to-use functional modules.

Background of the invention

The use of modular assemblies allows the realization of product families, using a common base, and each customized by different options or functionalities, including complications in the case of a mechanical watch movement.

The design of modules or sub-assemblies of very high precision makes it possible to combine mass production with quality products.

Modular subsets of watch movements are thus known from patent applications. EP11193173.9 and EP11193174.7 in the name of ETA SA. The mechanical modules described in these applications are pre-set and assembled irreversibly to ensure the durability of their adjustments.

However, in a conventional embodiment, the modules do not always allow the reduction in the number of components, which can both lower the cost of production, and a simplification of the assembly range, allowing medium technical staff to assemble and adjust the most complex functions.

Summary of the invention

Also, the invention proposes to provide subassemblies with reduced number of components, and assembly and adjustment of average complexity.

In particular, the mounting of a spiral spring is a delicate operation to automate. The design of a spiral spring integrated with an easier handling subassembly allows a better automation of the assembly.

The present invention uses for this purpose new micro-component manufacturing technologies, MEMS, "LIGA", lithography, and the like, to optimize the manufacture of such modules, presented here as subsets. These subassemblies can, depending on the case, be assembled together irreversibly as in the two above applications, or they can be positioned and assembled in a conventional manner.

For this purpose, the invention relates to a watch exhaust mechanism subassembly comprising at least one bridge and at least one spiral spring whose outer end is fixed to a peak, characterized in that at least one said spiral spring and said stud associated therewith form a unitary assembly with said bridge.

According to a feature of the invention, at least one said pin is adjustable in position and is immobilizable in a pre-set position by locking means.

According to a feature of the invention, said pin is fixed to said bridge by one-piece elastic return means with said pin and said bridge.

The invention also relates to a mechanical clockwork movement comprising at least one such subassembly.

The fact of making monolithic components, and in particular with the plate or bridges, has the advantage of reducing the number of parts, avoid assembly problems. The invention benefits from the precision of realization of these monolithic components (typically, the parts are for example made of silicon and thus benefit from a micrometric precision).

The monolithic subassembly has the main advantage of guaranteeing the distances and forming a mechanism, particularly an oscillator in a preferred application, ready to use.

• une précision garantie ;
• un niveau de frottements très réduit voire nul ;
• l'absence d'hystérèse dans les mouvements, du fait de l'absence de frottements ou du moins de leur niveau extrêmement réduit ;
• l'absence de lubrification ;
• l'absence de jeu ;
• l'absence d'usure.

The invention integrates in particular flexible guides, the advantages of which are:

• guaranteed accuracy;
• a level of friction very reduced or even zero;
• the absence of hysteresis in the movements, because of the absence of friction or at least of their extremely reduced level;
• lack of lubrication;
• the lack of play;
• the absence of wear.

Their manufacture induces limitations, including a limited displacement stroke, low return forces, and a limited load. However, these limitations are not prohibitive for many horological functions, particularly those relating to regulation.

These limitations are largely offset by the high accuracy of the centers, the small number of components to achieve and therefore reduced complexity and assembly time. A subset according to the invention has a great industrial advantage: the mechanism, in particular an oscillator, as a subset forms a component ready to mount in a movement. Nothing prohibits, moreover, to design an entire movement in the form of a subset according to the invention.

Brief description of the drawings

• la figure 1 représente, de façon schématisée et en vue de côté, un sous-ensemble selon l'invention, pour le cas particulier d'un mécanisme d'échappement, et comportant un ressort-spiral réalisé de façon monobloc avec un pont ;
• la figure 2 représente, de façon similaire à la figure 1, une variante similaire ;
• la figure 3 représente, de façon similaire à la figure 1, une variante où le spiral est réalisé monobloc avec un piton, lui-même réalisé de façon monobloc avec le pont auquel il est relié par des moyens de rappel élastique intégrés ;
• la figure 4 représente, de façon similaire à la figure 1, une variante où le spiral est réalisé monobloc avec un piton, lui-même réalisé de façon monobloc avec le pont, et où l'extrémité externe du spiral est pincée par des goupilles monobloc avec le pont, et dont au moins une est reliée par des moyens de rappel élastique intégrés au pont ; la figure 5 représente, en vue en plan et en vue de côté, des goupilles classiques avec jeu, et la figure 6 représente, en vue en plan et en vue de côté, une telle paire de goupilles pinçant le spiral sous l'effet de moyens de rappel élastique intégrés ;
• la figure 4A représente un pont comportant, pour le pivotement d'un balancier destiné à recevoir l'extrémité intérieure du ressort-spiral, un pivot logé dans un porte-palier relié au pont par des moyens de rappel élastique ;
• les figures 7, 8 et 9 représentent, en vue en plan, un sous-ensemble monolithique comportant des moyens de réglage en position d'un composant lui aussi intégré à cet ensemble, ces moyens de réglage étant immobilisables en position par des moyens de blocage ; la figure 7 illustre le réglage d'un pivot d'accrochage d'un ressort-spiral par des moyens de réglage élastique comportant un peigne, le blocage en position de ce peigne dans une position réglée, et un mécanisme de verrouillage contrôlant ces moyens de blocage ; la figure 8 illustre un exemple similaire où le peigne est maintenu entre deux lames flexibles et forme un composant bistable ; la figure 9 illustre un mécanisme similaire avec un peigne immobilisant un index situé à l'extrémité d'une lame flexible, le peigne étant plaqué sur cet index par une lame-ressort de blocage elle-même immobilisée par un doigt de verrouillage ;
• la figure 10 représente une section passant par l'axe d'un pivot avec un palier anti-chocs monobloc avec une platine ou un pont ;
• la figure 11 représente, de façon schématique, un mouvement d'horlogerie comportant un sous-ensemble selon l'invention.

Other features and advantages of the invention will appear on reading the detailed description which follows, with reference to the appended drawings, in which:

• the figure 1 shows schematically and in side view, a subset according to the invention, for the particular case of an exhaust mechanism, and comprising a spiral spring integrally formed with a bridge;
• the figure 2 represents, similarly to the figure 1 a similar variant;
• the figure 3 represents, similarly to the figure 1 a variant where the hairspring is made in one piece with a peg, itself made integrally with the bridge to which it is connected by integral elastic return means;
• the figure 4 represents, similarly to the figure 1 , a variant where the hairspring is made in one piece with a pin, itself made in one piece with the bridge, and where the outer end of the hairspring is pinched by one-piece pins with the bridge, and at least one of which is connected by elastic return means integrated in the bridge; the figure 5 represents, in plan view and in view of side, classic pins with play, and the figure 6 represents, in plan view and in side view, such a pair of pins pinching the spring under the effect of integrated elastic return means;
• the Figure 4A represents a bridge comprising, for the pivoting of a rocker for receiving the inner end of the spiral spring, a pivot housed in a bearing carrier connected to the bridge by elastic return means;
• the Figures 7, 8 and 9 represent, in plan view, a monolithic subassembly comprising adjustment means in position of a component also integrated in this assembly, these adjustment means being immobilizable in position by locking means; the figure 7 illustrates the setting of a hooking pin of a spiral spring by elastic adjustment means comprising a comb, the locking in position of this comb in a set position, and a locking mechanism controlling these locking means; the figure 8 illustrates a similar example where the comb is held between two flexible blades and forms a bistable component; the figure 9 illustrates a similar mechanism with a comb immobilizing an index located at the end of a flexible blade, the comb being pressed on this index by a locking spring blade itself immobilized by a locking finger;
• the figure 10 represents a section passing through the axis of a pivot with a shockproof one-piece bearing with a plate or a bridge;
• the figure 11 schematically represents a watch movement comprising a subassembly according to the invention.

Detailed Description of the Preferred Embodiments

The invention relates to the field of watch mechanisms, and more particularly to movements incorporating ready-to-use functional modules.

The invention relates to a subset 1 of a watch exhaust mechanism, comprising at least one bridge 3 and at least one spiral spring 71 whose outer end is fixed to a pin 73.

According to the invention, at least one such spiral spring 71 and the stud 73 associated therewith form a one-piece assembly with the bridge 3.

• La figure 1 illustre un cas où le piton est solidaire d'une plaque 72, dans le plan du spiral 71, parallèle au plan du pont 3 proprement dit et solidaire avec lui, le tout formant un composant monobloc 20.
• La figure 2 illustre un cas où le piton 73 est saillant du pont 3, et où l'extrémité du piton 73 est dans le plan du spiral 71, parallèle au plan du pont 3, le tout formant un composant monobloc 20.
• La figure 3 et la figure 4 illustrent des cas où le piton 73 s'étend à la fois sur deux niveaux : celui du spiral 71 et celui du pont 3, le tout formant un composant monobloc 20.

In an advantageous variant, as visible on the Figures 7 to 9 at least one such pin 73 is adjustable in position and is immobilizable in a pre-set position by locking means.

• The figure 1 illustrates a case where the stud is secured to a plate 72, in the plane of the spiral 71, parallel to the plane of the deck 3 itself and integral with it, all forming a monobloc component 20.
• The figure 2 illustrates a case where the pin 73 is protruding from the bridge 3, and where the end of the pin 73 is in the plane of the spiral 71, parallel to the plane of the bridge 3, all forming a monobloc component 20.
• The figure 3 and the figure 4 illustrate cases where the bolt 73 extends over two levels at the same time: that of the spiral 71 and that of the bridge 3, the whole forming a monobloc component 20.

As seen especially in the figure 2 or 3 , the hairspring 71 is made in one piece with a pin 73 to which it is attached by its outer turn 77. This pin 73 is itself integrally formed with the bridge 3, to which it is connected by second integral resilient return means 75 monobloc both with the pin 73 and the bridge 3. Preferably, the adjustment in position of this pin playing on the elasticity of the second elastic return means, is maintained by locking means, not shown on the figure 3 but of which an example is found in figures 7 and 9 .

The adjustment of the active length of the outer turn of the hairspring 71 can be done in different ways.

In a variant, the outer coil 77 of the spiral spring 71 is gripped by two pins 74A, 74B, integral with the bridge 3.

In another variant, at least one of the pins 74 is fixed to the upper bridge 3 by second elastic return means 76 integral with the at least one pin 74A or 74B and the bridge 3, and which tend to bring it closer to the other pin 74B or 74A.

The figure 4 represents a variant of the execution of the figure 3 , where the hairspring 71 is also made in one piece with a pin 73, itself made integrally with the bridge 3, and where the outer end of the hairspring is pinched, at a distance from the pin 73, by pins 74A and 74B monobloc with the bridge 3, together constituting the equivalent of a racket 74 to modify the active length of the hairspring 71.

In an achievement without play, as visible on the figure 6 at least one of these pins 74A and 74B is connected and fixed to the bridge 3 by elastic return means 76 also integrated in the bridge 3, which are integral with this at least one pin 74 and with the bridge 3, and which tend to bring it closer to the other pin 74.

While the figure 5 illustrates an embodiment with a very slight clearance, in which, the radial adjustment, independent, the pins 74A and 74B makes it possible to adjust the isochronism of the movement in the different positions.

These elastic return means 76 are in particular constituted by one or more flexible elements, located either in the plane of the spiral 71, or in the plane of the bridge 3, or in any other plane. In an advantageous variant, the hairspring 71 and / or the pins 74A or 74B may be locally notched in order to allow the realization of a discrete type of adjustment notch notch.

In order to easily perform a pre-adjustment of such a subassembly 1, at least one of its components is adjustable in position and is immobilizable in a pre-set position by locking means.

In a particular variant, illustrated by the Figures 7 to 9 the subassembly 1 comprises an adjustable mechanism in position 80, which comprises a rigid structure 81. This rigid structure 81 is preferably constituted by the bridge 3, and it carries, via at least one elastic blade 83 at least one component adjustable in position 82 (in particular constituted by a pin or holder of a pin 73) This adjustable component 82 comprises indexing means 84, which are arranged to cooperate with complementary indexing means 91 that comprises an adjustment mechanism 90. These complementary indexing means 91 are detachably mounted indexing means 84, and are lockable in the cooperation position by a locking mechanism 94 resiliently fixed to the structure 81. This blocking mechanism 94 is itself even subject to the action of a locking mechanism 98 which allows it to occupy, or a disengaged position in which the adjustment mechanism 90 is free, or a position engaged in the the locking mechanism 94 obstructs the adjustment mechanism 90. This locking mechanism 98 is also resiliently attached to the structure 81.

In a variant, this mechanism adjustable in position 80 carries an adjustable component in position 82 which carries a bearing 44 or a bearing holder 13 receiving the pivot of a rocker 41 for receiving the inner end of the spiral spring 71, with the same architecture as before.

In the case of figure 7 this adjustable component in position 82 comprises indexing means 84, which are arranged to cooperate with complementary indexing means 91, here constituted by a comb, or a toothed sector, which comprises an adjustment mechanism 90. These means complementary indexing 91 are mounted disengageable indexing means 84. They are still lockable in the cooperation position by a locking mechanism 94.

This blocking mechanism 94 is resiliently fastened to the structure 81 by at least one flexible element 96, and is preferably itself subjected to the action of a locking mechanism which allows it to occupy, or a position disengaged in which the adjustment mechanism 90 is free, or an engaged position in which the blocking mechanism 94 obstructs the adjustment mechanism 90. This locking mechanism comprises at least one flexible element 98 springing and elastically fixed to the structure 81, this at less a flexible element 98 here comprises a spout 99 which cooperates with a spout 97 of the blocker 94 to keep the blocker spread during adjustment in position, or with a complementary stop surface 95 of the blocker 94 in the safety of the blocker when the adjustment in position is performed. The latter is shaped fork, so as to limit the stroke of an arm 93 that includes the comb 91.

The figure 8 illustrates a similar example where the comb 91 is held between two substantially aligned flexible blades 92 and 92A, and forms a bistable component, working in buckling substantially aligned, the assembly can occupy two stable positions: a first armed position A where the comb 91 cooperates with a finger 84 of a mobile peg 82, and a second disarmed position B where it is disengaged.

The figure 9 illustrates a similar mechanism with a comb 91 immobilizing an index 84 located at the end of a flexible blade 83, the comb 91 being pressed on this index 84 by a locking spring blade 96 belonging to the blocker 94, itself immobilized by a locking pin 99 mounted on at least one flexible blade 98, this finger 99 cooperating with a stop surface 97 of the blade 96.

As has been seen above, this combined mechanism of adjustment, locking and locking, illustrated here for a particular application of adjusting a stud in a race concentric to the axis of a spiral, is applicable to a wide variety of applications: positioning of a bearing, an abutment, a racket pin, or other.

In a variant according to figure 10 , the bridge 3 forms a single-piece component that can not be dismantled with at least one anti-shock bearing for receiving a pivot of a rocker arm 41 intended to receive the inner end of the spiral spring 71, or of a component of the escape mechanism .

In particular, in an advantageous variant visible on the Figure 4A , the bridge 3 comprises, for the pivoting of a rocker arm 41 intended to receive the inner end of the spiral spring 71, a pivot 45 housed in a bearing holder 13 connected to the bridge 3 by elastic return means 14. similarly, such a pivot 45 can be arranged at the level of the plate 2.

The pivot 45 may be constituted by a conventional pivot or by a flexible guide.

In a particular version, the pivot 45 is a flexible one-piece guide with the bridge 3 or with the plate 2, as the case.

In another particular version, not illustrated, the rocker arm 41 has a one-piece end with a flexible guide and the bridge 3 (or respectively the plate 2), the rocker then has a stroke which is limited by the deflection of the flexible guide, which is then advantageously made in several stages to allow sufficient angular travel for the balance, which is then in one piece with the bridge 3 (or respectively the plate 2). More particularly, such a flexible guide may be constituted by the spiral spring 71 itself.

In another variant not shown, the rocker 41 is hooked to both the bridge 3 and the plate 2, on each side by a flexible guide constituting a spiral spring 71, these two spiral springs 71 exerting couples, or in the same sense, or in opposite senses.

Preferably these elastic return means 14 are integral with the bridge 3 and the bearing holder 13, and, in one variant, the pivot 45 is also part of this monobloc subassembly 1.

In a particular embodiment of the subassembly 1, the bridge 3 comprises at least one bearing 44 or 45, or a bearing holder 13 for receiving the pivot of a rocker arm 41 intended to receive the inner end of the spiral spring 71 , and at least this bearing 44 or 45, or this bearing holder 13, is made integrally with the bridge 3, and comprises a revolution range 46 for the radial retention of a shaft 47 of the balance 41, and a front surface 49 for the axial limitation of the end of this shaft 47, the revolution range 46 and the front span 47 being carried together by an elastic shock absorber 48 also integral with them.

In an advantageous embodiment, the subset 1 is made of silicon. The pivot points of the pivots 45 are defined, for example, by anisotropic etchings (KOH) in a silicon substrate. A version with an assembly of the stones is also possible. The big advantage is the very precise positioning of the pivot points (center distance, verticality).

Anti-shock can thus be partially or completely made in the plate: the spring of the shock can be achieved in common with the plate. One of the two (or both) stones can be made in common with the plate. Pivoting is then done directly in the silicon. The pivot points can be made directly in silicon with surface coatings of the DLC or other type. So there is no more stone, and the rotation points are positioned very precisely.

In a particular embodiment, the subassembly 1 according to the invention comprises breakable elements, intended to facilitate its assembly in an upper assembly, it is sufficient to then break these breakable elements to give one or more degrees of freedom to some of its constituents . In particular these breakable elements are located at the inner end of the hairspring, in connection with the bridge, and are broken only during assembly of the balance 41 and the attachment of the hairspring 71 to the shell of this balance.

In a particular variant, not illustrated, the subset 1 comprises the entirety of an escape mechanism.

In a particular embodiment, the intrinsic elastic return means that comprises the subset 1 comprise at least one bistable or multistable flexible element, as visible for example on the figure 8 , which shows a bistable element working in buckling, and having a comb 91 between two substantially aligned resilient blades 92 and 92A, the assembly being able to occupy two stable positions: a first armed position A where the comb 91 cooperates with a finger 84 of a mobile peg 82, and a second disarmed position B where it is disengaged.

In an advantageous embodiment of the subassembly 1 according to the invention made of silicon, the intrinsic elastic return means it comprises are prestressed in an oxidized state of silicon.

In an advantageous embodiment of the subassembly 1 according to the invention, the bridge 3 is made of micro-machinable material, or silicon, or oxidized silicon, and intrinsic elastic return means that it comprises are prestressed in a state oxidized silicon. Other materials according to MEMS or "LIGA" technologies can be implemented. Quartz, DLC, at least partially amorphous materials, metallic glasses, can, and not exclusively, be used for these applications.

A particular structuring of the bridge 3, and / or unbreakable integral components that it comprises, may make it possible to compensate for the effects of the expansion of these structural elements, or of the components of the mechanism of the subassembly 1. It is possible for example to make the bridge 3 in silicon, then to oxidize it, in order to work coherently.

The invention also relates to a mechanical clockwork movement 100 comprising at least one such subassembly 1.

Claims (12)

Subassembly (1) of a watch exhaust mechanism comprising at least one bridge (3) and at least one spiral spring (71) whose outer end is fixed to a peak (73), characterized in that at least one said sprung spring (71) and said peg (73) associated therewith form a one-piece assembly with said bridge (3). Subassembly (1) according to claim 1, characterized in that at least one said pin (73) is adjustable in position and is immobilizable in a pre-set position by locking means. Subassembly (1) according to one of the preceding claims, characterized in that said pin (73) is fixed to said bridge (3) by elastic return means (75) integral with said pin (73) and said bridge ( 3). Subassembly (1) according to one of the preceding claims, characterized in that said spiral spring (71) comprises an outer turn (77) which is clamped by two pins (74) integral with said bridge (3). Subassembly (1) according to the preceding claim, characterized in that at least one of said pins (74) is fixed to said bridge (3) by elastic return means (76) integral with said at least one pin (74) and said bridge (3), and which tend to bring it closer to the other said pin (74). Subassembly (1) according to one of the preceding claims, characterized in that said bridge (3) forms an unbreakable integral component with at least one anti-shock bearing for receiving a pivot of a balance (41) for receiving the inner end of said hairspring (71), or a component of said exhaust mechanism. Subassembly (1) according to one of the preceding claims, characterized in that said bridge (3) comprises, for the pivoting of a rocker (41) intended to receive the inner end of said spiral spring (71), a pivot (44) housed in a bearing holder (13) connected to said bridge (3) by elastic return means (14). Subassembly (1) according to one of the preceding claims, characterized in that it comprises a mechanism adjustable in position (80) having a rigid structure (81) carrying, via at least one elastic blade ( 83), an adjustable component in position (82) carrying a said pivot (73) and having indexing means (84) arranged to cooperate with complementary indexing means (91) that comprises an adjustment mechanism (90), said complementary indexing means (91) being disengageable mountable indexing means (84) and being lockable in the cooperation position by a locking mechanism (94) resiliently attached to said structure (81), said locking mechanism (94) being itself subjected to the action of a locking mechanism (98) which allows it to occupy, or a disengaged position in which said adjustment mechanism (90) is free, or an engaged position in which said blocking mechanism (94) interferes with said adjustment mechanism (90), said locking mechanism (98) being also resiliently secured to said structure (81) . Subassembly (1) according to one of the preceding claims, characterized in that it comprises a mechanism adjustable in position (80) having a rigid structure (81) carrying, via at least one elastic blade ( 83), an adjustable component in position (82) carrying a bearing (44) or a bearing support (13) for receiving the pivot of a rocker arm (41) intended to receive the inner end of said spiral spring (71) and comprising indexing means (84) arranged to cooperate with complementary indexing means (91) that comprises an adjusting mechanism (90), said complementary indexing means (91) being mounted disengageable indexing means (84) and being lockable in the cooperation position by a locking mechanism (94) elastically fixed to said structure (81), said locking mechanism (94) being itself subjected to the action of a locking mechanism (98) which authorizes it to occupy, or a loose position wherein said adjustment mechanism (90) is free, or an engaged position in which said blocking mechanism (94) interferes with said adjustment mechanism (90), said locking mechanism (98) also resiliently secured to said structure (81). Subassembly (1) according to one of the preceding claims, characterized in that said bridge (3) comprises at least one bearing (44) or a bearing holder (13) for receiving the pivot of a balance (41 ) for receiving the inner end of said spiral spring (71), and in that at least one said bearing (44) or bearing holder (13) is integrally formed with said bridge (3) and comprises a bearing of revolution (46) for the radial holding of a shaft (47) of said rocker (41), and a front bearing (49) for the axial limitation of the end said shaft (47), said revolution range (46) and said front span (47) being carried together by an elastic shock absorber (48) also integral with them. Subassembly (1) according to one of the preceding claims, characterized in that said intrinsic elastic return means it comprises are prestressed in an oxidized state of said silicon. Mechanical clockwork movement (100) comprising at least one subassembly (1) according to one of the preceding claims.

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