EP3839660B1 - Striking mechanism, timepiece and regulator - Google Patents

Description

The invention relates to the field of clocks, in particular wristwatches, with a mechanical clockwork. It relates in particular to timepieces with a striking mechanism, in particular a repeating striking mechanism, for example a minute repeater, and a regulator for such a striking mechanism.

Repeater striking mechanisms are complications for mechanical watches that allow the time to be reproduced acoustically at a point in time that can be selected by the user. Minute repeaters, in which hours, quarter hours and minutes are struck one after the other on a total of two different gongs, are particularly popular. The energy required for striking is supplied by pressing a triggering lever, stored in a spring barrel and released again during striking.

Repeater chimes and other chimes require a regulator that controls the speed of the chime and thus ensures an even sound. Known regulators have a rotary wheel which is provided with mass elements which are deflected outwards against a spring force during rotation due to the centrifugal force. in the Swiss patent 334 describes such a regulator, in which the mass elements are deflected until they come into contact with a stationary inner wall. The resulting friction causes the rotational movement limited, whereupon the mass elements are pulled back inwards due to the spring force. As a result, the rotational speed will increase again due to the lack of friction. A pendulum movement can result, with the rotational speed always oscillating around a speed value specified by the spring constants, at which the centrifugal force is just sufficient to deflect the mass elements against the spring force so far that they touch the inner wall.

It has also already been proposed to use another braking mechanism instead of a frictional force in such a regulator with mass elements, for example the generation of eddy currents in the surrounding element. It has also been proposed to regulate the speed in this way, without the mass elements having to rub against the inner wall, by achieving a balance between the torque generated by the drive on the one hand and the torque that is required to overcome the outward deflection of the mass elements inertia on the other hand results.

The rotary wheel required for the regulator is mounted on an axle that has a bearing on the top and bottom. This has the disadvantage that the regulator requires a relatively large amount of space.

It is an object of the present invention to provide a striking mechanism, a watch and a regulator which overcome the disadvantages of the prior art and which, in particular, enable a compact design.

These objects are solved by the invention as defined in the claims.

A striking train for a mechanical watch has a striking mechanism, a drive and a regulator. According to one aspect of the invention, the regulator has a base which can be mounted fixed to the housing and which rotatably supports a rotary wheel. At least two mass elements are arranged on the rotating wheel, which can be deflected radially outwards against a spring force by rotating the rotating wheel due to the centrifugal force in order to regulate the rotational speed of the rotating wheel. At least three bearing elements, for example ball bearings, are attached to the base, which engage peripherally, in particular from radially outside, on the rotating wheel in order to mount it relative to the base.

In contrast to the prior art, the rotary wheel is not mounted by a shaft that is attached concentrically to the axis of rotation and in turn is supported by a bearing with ball bearings below and above the rotary wheel, but rather along the periphery of the rotary wheel. As a result, the axial dimension of the regulator - ie its depth - can be reduced compared to the prior art. Overall flatter constructions are possible.

The regulator is therefore in particular free of a shaft or the like, which lies on the axis of rotation of the rotary wheel and supports it. The rotary wheel does not require a shaft.

The bearing elements cannot be moved relative to the base, for example in the circumferential direction, but can be rotated about a respective axis of rotation, as a result of which the rotary wheel rolls on the bearing elements as it rotates. The bearing elements can, for example, be ball bearing elements (ie have a ball bearing, for example by forming a ball bearing). Such have, for example. An inner element (e.g. an inner ring) fixed to the housing, an outer ring and a plurality of balls between the inner element and the outer ring, whereby the outer ring can rotate relative to the inner element with little resistance.

The base of the regulator may have a ring-like portion defining a rotationally cylindrical inner surface within which the rotary wheel rotates. At high turning speed, the mass elements touch this inner surface, which is fixed to the housing, radially on the outside. Due to the deflection of the mass elements to the outside and the consequently increasing moment of inertia and possibly due to the friction occurring when they touch, the rotational movement of the rotary wheel is slowed down, whereupon the mass elements are pulled back inwards by the spring force. As a result, the rotational movement is accelerated again until the mass elements are deflected outwards again and can touch the inner surface, etc. In this way, the rotational speed is controlled in such a way that it is around a state of equilibrium (e.g.: the mass elements barely touch the inner surface). oscillates around or possibly, with sufficiently large damping, occupies it.

In particular, exactly three bearing elements can be present, which are arranged, for example, distributed uniformly in the circumferential direction.

The presence of more than three bearing elements is also not ruled out. Four, five or even more bearing elements can also be used.

The bearing elements can be attached to the base in such a way that their radial position is adjustable. This enables fine adjustment, for example to achieve the best possible, backlash-free and noiseless turning behavior. The adjustability of the radial position can be ensured, for example, in that a bearing journal has a first bearing part which is fixed to the housing and a second bearing part which is arranged eccentrically in relation to the first bearing part. By rotating the bearing journal, the position of the second bearing section can be adjusted perpendicular to the axis of the first bearing section.

In addition to ball bearings, other bearing elements can also be considered, for example rollers, which in turn are mounted by plain bearings, or the bearing elements themselves can be designed as plain bearings, for example ruby bearings. As a further alternative, the bearing elements can also be designed as balls or rollers, which are guided in a corresponding groove of the housing or a base, so that the rotary wheel as a whole can be understood as a ring (inner or possibly outer ring) of a ball bearing. The only important thing is that storage from the periphery is possible and that the friction losses are not too great.

The bearing wheel forms a peripheral, radially outer or possibly inner running surface on which the bearing elements engage. For smooth rolling of the bearing elements, the running surface can be designed in such a way that it has no structure in the circumferential direction, but is smooth, i.e. it is constant as a function of the azimuth angle and in particular has no teeth or the like.

However, the running surface can form an encircling groove or possibly an encircling tongue, which interacts with a complementary structure of the bearing elements in order to fix the bogie in the axial direction. However, the complementary structure of the bearing elements can deviate from the structure of the running surface in terms of its configuration and dimensions such that generally only two contact points are formed per bearing element. This can be brought about, for example, by the respective groove having no curvature or a smaller curvature than the corresponding surface of the engaging element in the area of contact with the element (ring; spring) engaging in it. In one example, the bearing wheel has an outer circumferential groove that is roughly V-shaped, and the outer rings (rollers) of the bearing elements are convex in cross-section perpendicular to the axis of rotation to provide the two points of contact.

The mass elements are attached to the rotary wheel in particular in such a way that they can each be pivoted outwards about a pivot axis. In particular, they can be coupled to one another in such a way that they can only be deflected together, i.e. a deflection of one mass element causes a deflection of the other mass element by the same angle. Such a coupling can, for example, take place via a resetting gear which is geared to the mass elements; such a resetting gear wheel can in particular be arranged centrally on the impeller and can be arranged so as to be rotatable relative to it.

A solution with mass elements coupled to one another has the advantage that a single common spring is sufficient to bring about the restoring force. Two springs do not have to be used, and in particular two springs do not have to be matched very precisely to prevent imbalance.

The spring can be a spiral spring. In addition or as an alternative, the common spring can optionally act on the return gear.

In addition to the regulator, the present invention also relates to a striking mechanism, in particular a repeating striking mechanism, for example a minute repeater, with the regulator. The repetition striking mechanism has a mechanical control which queries the time in the mechanical clockwork and causes a sequence of blows of one or more hammers on one or more gongs depending on the time queried. The frequency of the hammer blows is controlled by the regulator.

The invention also relates to a watch, in particular a wristwatch, with such a striking mechanism.

Figur 1

Ein Schema der Bausteine eines Schlagwerks;

Figur 2

eine Ansicht des Regulators zusammen mit den ihn antreibenden Komponenten;

Figur 3

eine Ansicht des Regulators und der Komponenten gemäss Figur 3 aus einer anderen Sichtrichtung;

Figur 4

den auch in Figuren 2 und 3 sichtbaren Regulator nur mit dem ihn unmittelbar antreibenden Zahnrad;

Figur 5

eine Explosionsdarstellung der in Figur 4 gezeigten Komponenten;

Figur 6

eine Vorderansicht des Regulators mit dem Zahnrad;

Figur 7

den Regulator entlang der Ebene A-A in Fig. 6 geschnitten;

Figur 8

eine Explosionsdarstellung von Komponenten des Regulators, nämlich des Drehrades mit den daran angebrachten Elementen; und

Figur 9

ein Detail aus Figur 7.

The following drawings represent exemplary embodiments of the invention, on the basis of which the invention is described in detail. In the drawings, the same reference numbers indicate the same or analogous elements. The drawings show:

figure 1

A schematic of the building blocks of a percussion mechanism;

figure 2

a view of the regulator together with the components driving it;

figure 3

a view of the regulator and the components according to figure 3 from a different point of view;

figure 4

the also in figures 2 and 3 visible regulator only with the gear wheel directly driving it;

figure 5

an exploded view of the in figure 4 components shown;

figure 6

a front view of the regulator with the gear;

figure 7

the regulator along the plane AA in 6 cut;

figure 8

an exploded view of components of the regulator, namely the rotary wheel with the elements attached thereto; and

figure 9

a detail out figure 7 .

The functioning and implementation of the invention is shown below using various exemplary embodiments. It is understood that the invention is not limited to these embodiments, but also includes other embodiments consistent with the claims.

figure 1 shows very schematically the building blocks of an example of a percussion mechanism, namely a repetition percussion mechanism in the present case. The actuation of an actuating element 1, for example a lever, has the effect on the one hand that a mechanical energy store 2, for example a barrel with a spiral spring, is charged. On the other hand, it has the effect that a mechanical control 3 enables the energy stored in the energy store 2 to be directed via a gear (gear train) 4 to a percussion mechanism 5 on the one hand - for example with a hammer or several hammers, which hit one or several different sound elements, For example, gongs, hit - and on the other hand is delivered to a regulator 6. The controller works in such a way that it queries the current time from a movement 7 of the watch and depending on this causes a certain sequence of beats in the striking mechanism 5 .

Traditional striking mechanisms differ from repeating striking mechanisms in that they are not triggered by an actuating element, but rather automatically by the movement at specified times. It can also differ in that the mechanical control does not have to query the time but has a coding of the sequence of the impact sequences itself.

Mechanical controls and striking mechanisms for striking mechanisms, which can be quite complex, are known per se. Many variants of such percussion mechanisms are described in the literature. The advantages of the present invention do not depend on the structure of the mechanical control 3 and also not on the structure of the actuating element 1 or other winding mechanism, the mechanical energy store 2, the gear 4 and the striking mechanism 5. For these reasons, the following description of embodiments of the invention is limited to the description of the structure and mode of operation of the regulator.

The function of the regulator 6 is—this applies both to repetition striking mechanisms and to other striking mechanisms—to regulate the speed of the striking sequence in such a way that it is approximately independent of the state of the energy store, ie, for example, of the tension of the spiral spring. This is done by applying a speed-dependent resistance to a drive of a moving element of the regulator - in the present example the rotary wheel. The movement of the moving element of the regulator on the one hand and the impact mechanism on the other hand are coupled to each other.

figures 2 and 3 show the regulator 6 together with the components that drive it, with the energy store 2 and parts of the transmission 4. The energy store has a barrel 12 with a spiral strip spring 11; in 3 you can also see the winding stem 13.

Figures 4 to 7 show the regulator 6 together with the gear 41 of the transmission directly driving it. The regulator has a base 21 with an annular portion 22 defining an inner surface 23 of revolution cylindrical. In addition, there are several screw holes 24 on the base for attachment to an element fixed to the housing, for example a clockwork plate. Ball bearings 25 are fixed in place relative to the base via bearing journals 26 . Each ball bearing has an outer ring 27 and an inner element, namely an inner ring 28, the outer ring 27 being able to rotate relative to the inner ring with little friction due to the balls (rolling elements) 29 arranged therebetween. The rotary wheel 31 is rotatably supported by the ball bearings 25 relative to the base 21 .

The bearing journals 26 have a first, in figure 5 tenon section 71 below and a second, in figure 5 overhead trunnion 72 with a positioning plate 73 therebetween. The first trunnion section has a fixed position in the housing and is e.g. supported by a clockwork plate (not shown). The second trunnion part is mounted eccentrically relative to the first trunnion part and carries the respective ball bearing. By rotating the bearing journal, the position of the associated ball bearing can therefore be finely adjusted relative to the rotary wheel, for which purpose a screwdriver slot can optionally be present, as shown. The eyelets 30 (elongated holes) in the base 21, through which the second peg part protrudes, offer sufficient play for this purpose.

figure 8 shows the structure of the rotary wheel 31 and the components present on it. The rotary wheel has a toothed ring 32 and a bearing ring 33 attached thereto. The bearing ring 33 has an outer surface 34 which is provided with a groove and which serves as a running surface. The radially outermost part of the outer rings 27 of the ball bearings can engage in the groove of the running surface so as to fix the position of the bearing ring and thereby enable it to rotate about its axis with little friction. The rotary wheel is laterally mounted by the three ball bearings 25, ie in a floating manner.

figure 9 shows a detail 7 . It can be seen that the outer surface 34 is approximately V-shaped in cross-section. In the present example, due to the approximately V-shaped configuration of the groove forming the running surface and the convex shape of the outer rings 27, there are only two contact points 61 per ball bearing, which minimizes resistance.

As an alternative to a groove, the outer surface of the bearing ring could also have a projection which engages in a corresponding groove in the outer rings of the ball bearings.

The outer surface can be coated with an abrasion-resistant material that minimizes rolling friction, for example Diamond Like Carbon (DLC). Otherwise, the materials used can be metals or composite materials, in particular special plastics, or ceramics that are considered suitable for the purpose described, e.g. high-quality steels, titanium alloys, etc.

On the bearing ring 33 there is also an in 8 particularly visible web 35 attached or available. Next, a first and a second mass element 51 and 52 are attached to the rotary wheel. The mass elements 51, 52 are pivotably attached to the bearing ring 33 via a respective attachment pin 53 (an attachment to the web or possibly the toothed ring 32 would also be conceivable as an alternative).

The regulator also has a reset mechanism, which resets the mass elements in the ground state to the in 4 position shown and which opposes the centrifugal force mentioned the spring force. This reset mechanism has a coil spring 54 and a reset gear 57 . The resetting gear wheel 57 is non-rotatably connected to an inner ring 56 of the spiral spring 54 by a connecting element 58 . Inner ring 56, connecting element 58 and return gear 57 are rotatably mounted together on web 35, for which a central pin 59 is used. The mass elements each have a toothing 61 which engages in the teeth of the return gear 57 . An outward deflection of the mass elements causes the reset gear wheel 57 to rotate. Because an external coupling structure 55 of the spiral spring is suspended in a spring pin 37 of the web 35, and because the reset gear wheel is coupled to the inner ring 56 of the spiral spring in a rotationally fixed manner, this occurs against a spring force of the spiral spring 54.

Due to this construction, a single spring, here the spiral spring 54, is sufficient to exert the necessary restoring force on both mass elements 51, 52 at the same time.

In addition, the two mass elements are always deflected synchronously. In contrast to a construction with one spring per mass element, it cannot happen that one mass element is deflected further than the other.

The same effect could also be achieved if the spiral spring were fastened on the inside in a rotationally fixed manner to the bearing ring or web and, on the outside, would act on one of the mass elements and the mass elements would be coupled via a freely rotatable gear wheel.

Claims (15)

1. A regulator for a striking mechanism for a mechanical watch, comprising a base (21) which can be assembled in a fixed manner with regard to the housing, and a rotary wheel (31), wherein the rotary wheel is rotatably mounted relative to the base and carries at least two mass elements (51, 52) which by way of a rotation of the rotary wheel are deflectable radially outwards counter to a spring force on account of the centrifugal force, in order to regulate the rotation speed of the rotary wheel, characterised in that at least three bearing elements are attached to the base (21), said bearing elements engaging peripherally on the rotary wheel (31) in order to mount this relative to the base.
2. A regulator according to claim 1, wherein the bearing elements are ball bearings (25).
3. A regulator according to claim 1, wherein the rotary wheel (31) comprises a radially outer outside surface (34) which serves as a running surface for the bearing elements.
4. A regulator according to claim 3, wherein the outer surface (34) forms a groove into which an outer ring (27) of the bearing elements engages.
5. A regulator according to one of the preceding claims, wherein the mass elements (51, 52) are coupled onto one another so that they can only be deflected together.
6. A regulator according to claim 5, comprising a single spring element which commonly exerts the spring force which counteracts the centrifugal force, upon both mass elements (51, 52).
7. A regulator according to claim 6, wherein the spring element is a spiral spring (54).
8. A regulator according to one of the claims 5-7, comprising a restoring gearwheel (57) which is rotatably fastened to the rotary wheel and which is toothed with the mass elements (51, 52) and is rotatable relative to the rotary wheel by way of the deflection of these.
9. A regulator according to one of the preceding claims, wherein at least one of the bearing elements is mounted by a bearing portion whose position relative to the base can be set at least in the radial direction for the purpose of adjustment.
10. A regulator according to claim 9, wherein the bearing portion is an eccentrically attached pin portion (72) of a bearing pin (26).
11. A regulator according to one of the preceding claims, wherein the base comprises an in particular rotationally cylindrical inner surface (23) which is arranged such that the mass elements on account of the centrifugal force can be deflected to such an extent that they contact the inner surface (23).
12. A regulator according to one of the preceding claims, wherein the rotary wheel comprises a toothed ring (32) with a toothing, into which a gearwheel of a gear can engage, as well as a bearing ring (33), and wherein the bearing elements engage on the bearing ring (33) of the rotary wheel.
13. A striking mechanism for a mechanical watch, comprising a striking device (5), a drive and a regulator according to one of the preceding claims.
14. A striking mechanism according to claim 13, which is designed as a repetition striking mechanism, in particular minute repetition and comprises an actuation element (1) via which a bell strike can be manually activated.
15. A wristwatch comprising a striking mechanism according to one of the claims 13 or 14.

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