CH709282B1 - Anchor suspended for watch exhaust. - Google Patents

Abstract

The invention relates to an anchor system (1) for a timepiece comprising an anchor (3) comprising a first part (5) extending in a first plane and suspended by at least one elastic element (19, 20). intended to be secured to a frame element of a timepiece and come from a part with the first part (5), so that the anchor (3) can pivot about a virtual axis of rotation . According to the invention, the anchor (3) comprises a second part (7) extending in a second plane and mounted directly or indirectly on the first part (5), at least one of the first part (5) and the second part (7) comprising pallets (9) intended to cooperate with an escape wheel that includes the timepiece.

Description

Description

Technical Field [0001] The present invention relates to the field of watchmaking. It relates, more particularly, a suspended anchor system for an escapement of a watch movement.

State of the art [0002] Document EP 2 037 335 proposes an anchor suspended by elastic elements from a piece with the anchor and intended to be secured to a frame member of a clockwork movement. This arrangement eliminates the physical pivot axis of the anchor, which therefore rotates around a virtual axis defined by the geometry of the anchor and elastic members. The friction due to the axis and its bearings are eliminated.

This anchor system is manufactured by a micro-machining process from a plate of a suitable material, for example by etching a silicon wafer. Subsequently, conventional pallets are attached to the anchor.

However, this system has several disadvantages. The constraints related to its manufacturing process limit it to forms extending in a single plane. As a result, for example, the possibilities of changing the positioning and geometry of the elastic elements are limited. In addition, in case of damage, the anchor system must be completely replaced, which can be expensive in the case where it occupies a large area on the wafer from which it is manufactured.

The object of the invention is, therefore, to provide an anchor system in which the aforementioned defects are at least partially overcome.

Disclosure of the invention [0006] More precisely, according to a first aspect, the invention relates to a timepiece anchor system comprising an anchor comprising a first part extending in a first plane and suspended by a less an elastic element, for example having at least one arm, come from a room with the first part. The at least one elastic element is intended to be secured to a frame element of a timepiece, and the first part is suspended by the at least one elastic element, preferably by at least two elastic elements, of such that the anchor can pivot about a virtual axis of rotation.

According to the invention, the anchor further comprises a second part extending in a second plane and mounted at least indirectly on the first part (that is to say indirectly or directly), the first part and / or the second part comprising pallets for cooperating with an escape wheel that includes the timepiece.

Therefore, the first and second parts can be manufactured separately, giving greater freedom of design to the system, because part of the anchor, which may optionally comprise a fork and / or at least one pallet, is arranged in another plane than the elastic elements. This leaves more room in their plan for the elastic elements. In addition, in case of replacement of the pallets, for example to change the penetrations of the pallets of the anchor in the teeth of the escape wheel, only the second part must be reworked or replaced, and there is more than need to manipulate the entire system to secure the pallets, reducing the risk of breaking it.

Advantageously, the second part is at least partially flexible and comprises at least two contact surfaces bearing against abutments that includes the first part, the distance between said contact surfaces when the second part is in disassembled position being different from the distance between the portions of said stops intended to be in contact with said contact surfaces. Attachment and easy detachment by wedging or clipping of the second part on the first part can be achieved.

Advantageously, the stops are formed by pins integral with the first part, said contact surfaces being formed by indentations that comprises the second part.

Advantageously, the second portion comprises a fork intended to cooperate in a conventional manner with an oscillator, such as a sprung balance, that includes the timepiece. By also arranging the fork on the second part of the anchor, any interaction with the escape wheel and the oscillator can take place in a plane different from that of the elastic elements, maximizing the space available for the elastic elements.

Advantageously, said pallets came from a room with the second part, which provides an extremely simple construction.

Advantageously, the second part comprises stress limiting means arranged to limit the stress on the second part when it is mounted on the first part. The risk of breaking the second part when it is mounted on the first part is thus reduced. Preferably, the stress limiting means are formed by at least one stress limiting abutment projecting from the second part.

Advantageously, the second part comprises handling means, making it easy to manipulate the second part by means of a suitable tool.

Advantageously, the system comprises at least one prestressing adjustment system of at least one elastic element. Therefore, the angular stiffness of the anchor and / or its angular rest position can be adjusted by modifying said preload.

Advantageously, the adjustment system comprises an adjustment member movable in rotation about a physical or virtual axis. The adjusting member is mounted integral with one end of a resilient member, and the angular position of said adjusting member is adjustable. Optionally, the adjusting member comprises a needle located in front of a ladder to indicate said preload. Advantageously, the needle is formed of a nose carried by the adjusting member, and the scale is formed of a toothing provided on a frame member arranged to support the anchor system. This latter arrangement makes it possible to indicate the prestressing without requiring additional markings.

BRIEF DESCRIPTION OF THE DRAWINGS Further details of the invention will appear more clearly on reading the description which follows, made with reference to the appended drawings in which: FIG. 1 is a perspective view of an anchor system according to the invention; Fig. 2 is an exploded view of the anchor system of FIG. 1; Fig. 3 is a perspective view of the adjusting devices; Fig. 4 is a schematic view of the principle of attachment of the second part to the first part; Fig. 5 is a schematic view of the principle of attachment of the second part to the first part in a variable manner; and fig. 6 to 11 are schematic views of variants of the second part.

Embodiments of the Invention [0018] FIG. 1 illustrates an anchor system 1 according to the invention in the mounted position, and FIG. 2 illustrates the same system 1 in exploded view. This system 1 comprises an anchor 3 formed by a first part 5, relatively rigid, which is located in a first plane and forms the arms of the anchor, and a second portion 7, at least partially flexible, which is located in a second plane different from the foreground. This second part 7 comprises pallets 9 located at the free end of two arms 10, and a fork 11, located near the junction of the other ends of the arms 10, where the arms 10 are connected by a transverse element 12. 9 pallets interact with an escape wheel (not shown), while the fork 11 cooperates with an ankle connected to a sprung balance (not shown) in a conventional manner. Alternatively, traditional pallets or dowels can be secured to the second part 7 in a conventional manner. It is also possible to arrange the pallets on the first part 5, or even two pallets on one of said parts 5, 7, and at least one pallet on the other, so as to interact with a multi exhaust wheel -levels such as that described in EP 1 517 197. It should be noted that any suitable material can be used to build the first part 5 and the second part 7, and that the materials used for each part can be the same or different. For example, one or more materials could be chosen from metals or alloys (crystalline or amorphous), silicon-based materials (such as monocrystalline or polycrystalline silicon, its oxide, its carbide, its nitride, etc.), alumina-oxide-based materials (such as corundum, ruby, sapphire), carbon-based materials (such as diamond or diamond-like carbon [DLC]), etc.

The second part 7 is fixed on the first part 5 by wedging between two pins 13 fixed in appropriate openings 14 provided in the first part, for example by gluing, driving, welding by laser, or any other appropriate means. These pins 13 form abutments against which the contact surfaces that the second portion 7 has are supported in the mounted position. For this purpose, the second part 7 is provided with two notches 15 each having at least one contact surface, adapted to interact with the pins 13. In fact, the second part 7 is clipped onto the pins 13. Although the notches have have been illustrated here as having a wall along an arc of a circle, it is also possible that the notches have another shape, for example polygonal or a succession of arcs of circles.

To allow jamming or clipping of the second part 7 of the pins 13, the second part has a degree of flexibility. This flexibility is given by all or part of the arms 10 and / or all or part of the transverse element 12. Alternatively, the two arms 10 can be articulated, flexibility being provided by a suitable elastic element.

In the examples illustrated in FIGS. 1, 2 and 4, the distance between the contact surfaces that comprise the notches 15 when the second part 7 is in disassembled position is greater than the distance between the corresponding contact areas located on the pins 13, which allows to join together the second portion 7 to the pins 13 without clearance. Therefore, in the mounted position, the second portion 7 exerts forces tending to separate the pins 13, any clearance between the pins 13 and the second portion 7 is thus eliminated. In the opposite case, that is to say when the pins 13 are wedged between indentations 15 located face to face inside the second part 7 (see Fig. 5), the ratio between the distances as well as the forces are also reversed.

Alternative design of the second part 7 are discussed in more detail below with reference to FIGS. 2, and 4-11.

To prevent the second portion 7 can move in a direction parallel to the axis of the pins 13, each pin 13 is provided with flanges 17a, 17b, serving as positioning stops of the second portion 7 in said direction mentioned above. . The upper flange (with respect to the view of Fig. 2) 17a also serves to position the pin 13 relative to the first portion 5, but is not essential. In addition, it should be noted that the collars can be replaced by any appropriate form of abutment, and that they are even superfluous in the case where the second part 7 is fixed by gluing or welding on the pins 13.

The first part 5, and the other components attached thereto, is suspended by elastic members 19, 20, integrally formed with the first portion 5, and constructed in the form of a blade. The elastic elements 19, 20 are located at least partially in the same plane as the first part. Two main elastic elements 19 extend rectilinearly from the first part 5 to a rigid frame 21 intended to be fixed on a frame element of a clockwork movement, such as a plate or a bridge, for example by screwing. Other forms for the main elastic elements are conceivable, such as curves or shapes having one or more discontinuities. In the illustrated variant, secondary elastic elements 20 extend from a single point on the first part 5 in the form of a single blade, and then separate into two distinct elastic elements, which are each connected to a device adjustment 23, which adjusts the prestressing of the secondary elastic elements 20 and thus to vary the force exerted by the main elastic elements 19, and thus the angular stiffness of the anchor. As illustrated, the secondary elastic members 20 consist of two straight sections connected by an angle of between 70 ° and 110 °. Alternatively, the secondary elastic members 20 may each extend from a respective junction point located on the first portion. Other forms of secondary elastic members 20 are naturally conceivable, such as curved shapes. The adjusters 23 will be described in more detail below.

These elastic elements 19, 20 are arranged such that the first part 5 can pivot about a virtual axis of rotation, substantially perpendicular to the plane of the anchor system 1, in response to the forces exerted on the second part 7 by the escape wheel and the peg connected to the sprung balance (not shown) during operation of the exhaust. Therefore, no physical axis of rotation, i.e. no rod or shaft, is needed for the pivoting of the anchor, and the friction associated therewith can be avoided.

According to a non-illustrated alternative construction, the second part 7 is simply attached, without jamming, to the first part 5, for example by gluing, laser welding, diffusion welding, or any other suitable method. In addition, as an alternative to the separate pins 13, the first part 5, the elastic elements 19, 20 etc. could be manufactured by an SOI process ("Silicon on insulator"), to form pins 13 in one piece with the first part 5. For such a construction without jamming, the second part 7 could simply be provided with openings arranged to receive the pins 13.

FIG. 3 illustrates on a larger scale the adjustment devices 23. As illustrated, the latter comprises a sub-frame 25, located inside the frame 21 and integrally formed therewith, serving as support for two adjustment members 27, to which the ends of the secondary elastic members 20 are attached. Alternatively, this sub-frame 25 can be made superfluous by arranging the various components directly on the frame 21.

Each adjustment member 27 has an opening 29, here illustrated in square form, adapted to receive a shaft mounted on a frame member, preferably on a rooster. This shaft (not shown) may be frictionally mounted on the frame or alternatively the opening 29 may be circular, the shaft being integral in rotation with the frame and the opening 29 being mounted to friction on the shaft. The adjusting member 27 further comprises an elongate arm 31 to which the end of the respective secondary elastic element 20 is attached, and a spout 33, which faces the teeth 35 of the sub-frame 25. to form a device for indicating the prestressing. Indeed, the spout 33 acts as a needle and the toothing 35 serves as scale. At the end of the elongate arm 31 opposite that of the point of attachment of the secondary elastic element 20 is a resilient support member 37, connecting the adjustment member to the sub-frame 25 and supporting the adjusting member 27. It should be noted that the elastic support member 37 is optional. By using an ad hoc tool, each of the adjustment members 27 can be positioned in any angular position, where it is retained by a greasy friction which is strong enough to overcome the force of the springs 20 and 37, but low enough to allow the pivoting of the adjustment members 27 by the watchmaker.

In order to adjust the anchor system 1, the watchmaker thus rotates the adjustment members 27 so that the point of attachment of the secondary elastic elements 20 away from the first part 5, that is to say say in the clockwise direction for the adjusting member 27 on the right in the figures, and in the counter-clockwise direction for the adjustment member 27 on the left. Such pivoting applies prestressing to the two secondary elastic elements 20 and the two main elastic elements 19, which is proportional to the pivot angle of the adjustment member 27, and which would pull the first part 5 towards the adjustment members 27 if said first part 5 was not retained by the main elastic elements 19. The greater this prestress, the smaller is the angular stiffness of the anchor 3.

In addition, beyond a certain prestressing value, which will depend on the geometry of the elastic elements 19, 20 chosen, the main elastic members 19 flambé slightly, and the anchor 3 can become bistable because of this buckling. It is nevertheless noted that this bistability is not necessarily sought, but can be applied advantageously, if necessary.

It should also be noted that, if the two adjustment members 27 are asymmetrically adjusted, the angular rest position of the first part 5 can be slightly modified.

It goes without saying that the adjustment members 27, and the teeth 35, can be arranged directly on the frame 21, which would make the sub-frame 25 superfluous. In addition, the positions of the spout and the toothing can be reversed, the lever 31 bearing the toothing 35, and the (sub) frame carrying the spout 33.

As an alternative embodiment, one can arrange the adjustment members so that each spout 33 enters the corresponding toothing 35. For this purpose, the resilient support member 37 exerts a force tending to penetrate the spout 33 into the toothing 35, the elastic support member 37 therefore also acting as a trigger spring. Each spout 33 and its respective toothing 35 thus together form an expansion system for indexing the angular position of each adjusting member 27 in a position, among a plurality of discrete and predetermined angular positions. It should be noted that no physical pivot axis is necessary in principle for the adjustment member 27 of this variant, but it is also conceivable to provide the movement, with which the anchor system is associated, with a such axis, passing through each hole forming the opening 29 as described above for the embodiment of FIGS. 1 to 3.

It goes without saying that the adjusting device 23 can be applied to an anchor suspended independently of the construction of the two-part anchor described here. For example, it can be used with a hanging anchor of the form described in EP 2,037,335, or any other type.

FIG. 4 schematically illustrates the principle of assembly of the second portion 7 of the pins 13. This figure shows the second portion 7 and the pins 13 in disassembled position, wherein the distance between the notches 15 is greater than that between the pins 13 More specifically, in the disassembled position, a distance d-ι between the parts closest to the pins 13 is less than a distance d2 between the parts of the contact surface of the notches 15 intended to be in contact with said parts of the pins 13 In the case where the pins are of circular section and the indentations follow corresponding circular arcs, the inter-axis of the pins is less than the inter-axis of said arcs of the circle.

To mount the second part 7 on the pins 13, just approach the arms 10, thus bending the transverse portion 12 and / or the arms 10, and clip the notches on the pins 13. The effort that the second part 7 exerts on the pins therefore acts to the outside. To dismount the second part 7, the arms 10 are brought together, and the second part 7 is moved away from the pins 13.

FIG. 5 illustrates an alternative construction of the second part 7, in which the orientation of the notches 15 is reversed, that is to say that the notches 15 are arranged facing each other, open towards the inside. As a result, the pins 13 are wedged between the indentations 15 in the mounted position. The distance separating the pins 13 is greater than that separating the indentations 15, that is to say that d3> d4, d3 and d4 being defined complementary to di and d2 above.

To mount this second part 7 alternative to the pins 13, simply move the arms 10, thus bending the transverse portion 12 and / or the arms 10, and clip the notches on the pins 13. The effort that the second part 7 exerts on the pins therefore acts inwardly. To dismount the second part 7, the arms 10 are again spread apart, and the second part 7 of the pins 13 is lifted.

Figs. 6 to 11 schematically illustrate several variants of the second part 7 of FIG. 4.

The second part 7 of FIG. 6 presents means for limiting the stress exerted during its mounting on the pins 13. These means consist of two limit stops 41 extending towards one another, and are arranged so that, when the arm 10 of the second part 7 approach during assembly, the two limit stops 41 come into contact before the stresses applied to the second part 7 exceed the elastic limit of the material. The risk of breaking the second part 7 during assembly is thus reduced.

The second part 7 of FIG. 7 shows handling means 43, arranged to facilitate handling of the second part 7 during (mounting). In this example, these handling means are formed by notches 43 located on the outer side of the arms 10 which serve as support points for a tool such as tweezers.

In the second part 7 of FIG. 8, the stress limiting means and the handling means have been combined into two hollow protuberances 45 extending towards one another, the opening 47 inside the protuberances 45 being adapted to receive a tool ad hoc for the manipulation of the second part 7.

FIG. 9 illustrates a variant of the second part 7 of FIG. 6, wherein the stress limiting means is constituted by a single stop 41 extending at one of the notches 15, formed such that its distal end comes into contact with the other arm 10 before the constraints maximum allowable levels are reached.

FIG. 10 also illustrates a variant of the second part 7 of FIG. 6, wherein the stress limiting means are arranged between the notches 15 and the pallets 9.

FIG. 11 also illustrates a variant of the second part 7 of FIG. 7, in which the handling means 43 are arranged projecting from the second part 7, in the form of protuberances extending outwards. With this variant, the assembly and disassembly of the second part are relatively easy: it suffices to place the pins 13 of the first part 5 and the second part 7 in the same plane, to immobilize the first part 5 and to push the second part 7 using the protuberances 43.

It goes without saying that the handling means and the stress limiting means can be arranged in any way according to the wishes of the watchmaker. In addition, the characteristics of the variants of the second part 7, illustrated in FIGS. 6 to 11, can be combined in any non-contradictory way.

Claims (12)

claims Anchoring system (1) for a timepiece comprising an anchor (3) comprising a first portion (5) extending in a first plane and suspended by at least one elastic element (19, 20) intended to be secured to a frame member of a timepiece and come from a part with the first part (5), so that the anchor (3) can rotate about a virtual axis of rotation; characterized in that the anchor (3) comprises a second portion (7) extending in a second plane and mounted directly or indirectly on the first portion (5), at least one of the first portion (5) and second part (7) comprising pallets (9) intended to cooperate with an escape wheel that includes the timepiece. 2. anchor system (1) according to the preceding claim, wherein the second portion (7) is at least partially flexible and comprises at least two contact surfaces (15) bearing against abutments (13) that comprises the first part (5), the distance between said contact surfaces (15) when the second part (7) is in disassembled position being different from the distance between the portions of said stops (13) intended to be in contact with said contact surfaces ( 15). 3. Anchor system (1) according to the preceding claim, wherein the stops are formed by pins (13) integral or integrally with the first part (5), said contact surfaces being formed by indentations (15) that comprises the second part (7). 4. anchor system (1) according to one of the preceding claims, wherein the second portion (7) comprises a fork (11) for cooperating with an oscillator that includes the timepiece. 5. anchor system (1) according to one of the preceding claims, wherein said pallets (9) are integrally formed with the second part (7). 6. anchor system (1) according to one of the preceding claims, wherein the second portion (7) comprises stress limiting means arranged to limit the stress experienced by the second part (7) when mounted on the first part (5). 7. anchor system (1) according to the preceding claim, wherein the stress limiting means are formed by at least one stress limiting abutment projecting from the second portion (7). 8. anchor system according to one of the preceding claims, wherein the second part comprises handling means. 9. System according to one of the preceding claims, characterized in that it comprises at least one adjusting device (23) prestressing the at least one elastic element (20). 10. anchor system (1) according to the preceding claim, wherein the adjusting device (23) comprises a control member (27) pivotable about a physical or virtual axis, one end of the at least one elastic member ( 20) being integral with said adjusting member (27), the angular position of said adjusting member (27) being adjustable. 11. anchor system (1) according to the preceding claim, wherein the adjusting member (27) comprises a needle (33) facing a scale (35) to indicate said prestressing. 12. anchor system (1) according to the preceding claim, wherein the needle (33) is formed of a spout (33) carried by the adjusting member (27), and the scale (35) is formed of a toothing (35) provided on an element of a frame that supports said anchor.