HK1199311B - Oscillator with tuning fork for mechanical timepiece movement - Google Patents

Description

Technical field

The present invention relates to a mechanical clock-moving freed-discharge oscillator with a resonator of the clock-type, at least one first oscillating branch of which is designed to oscillate on either side of a first axis and has at least one first wedge associated with at least one first fork of an anchor, to rotate the latter between first and second angular positions and alternately lock and release an exhaust wheel.

It is known that such a mechanism allows, in connection with a source of mechanical energy, to maintain the oscillations of the resonator which is the tuning fork and thus to define an oscillator.

The high quality factor of a resonator like a tuning fork, which is about ten to fifty times that of a conventional spiral swing, makes it attractive for watchmaking applications.

In addition, the present invention also concerns a watch movement equipped with such an oscillator and a watch part, in particular but not exclusively of the wristwatch type, equipped with such a watch movement.

State of the art

Many watchmaking devices with a tuning fork as a resonator have already been disclosed in the state of the art.

For example, the patent FR 73414 A, issued in the name of Louis-François-Clément Breguet on the basis of an application filed in 1866, describes a clock whose mechanical resonator is a tuning fork. A first branch of this tuning fork carries a wedge arranged so as to be trapped in a tidy dwelling in an anchor with two arms arranged to cooperate with an exhaust wheel, to alternately lock and release the latter, the anchor being pivoted on a building element of the clock movement.

In particular, Max Hetzel is the inventor of a large number of patented inventions relating to the use of a dial as an oscillator, which led to the production of the Accutron wristwatch (registered trade mark) marketed by Bulova Swiss SA.

The Accutron watch, however, includes an electronic oscillator as each branch of the corresponding dial carries a permanent magnet associated with a fixed electromagnet mounted on the watch body. The operation of each electromagnet is subject to the vibrations of the dial, via the magnets it carries, such that the vibrations of the dial are maintained by transmitting periodic magnetic pulses from the electromagnets to the permanent magnets. One of the branches of the dial drives a clicker to rotate the screws of the finishing gear of the watch.

The Commission has not yet decided whether to grant a Community guarantee to the United Kingdom of the amount of the aid in question, which is equal to the amount of the aid granted to the United Kingdom of Great Britain and Northern Ireland.

It should be noted that the Accutron coin is still currently marketed by Bulova Swiss SA.

The frequency stability of the oscillations of a tuning fork is used, by magnetic interaction, to stabilize the oscillations of a conventional-shaped swing, thus having a lower quality factor than that of the swing. To this end, the branches of the tuning fork on the one hand, and the swing on the other, carry permanent magnets arranged to cooperate with each other. The corresponding interaction allows both to maintain the oscillations of the tuning fork and to stabilize the frequency oscillations of the swing.

However, although this is not explicitly stated in the patent, it is obvious that this mechanism is necessarily coupled to a mechanical exhaust to convert the periodic oscillations of the balance into a one-way movement to drive the motors of a finishing gear. Thus, it is likely that the balance is coupled to a conventional mechanical exhaust arranged to maintain the oscillations. Therefore, the mechanism described in this document improves the stability in the frequency of oscillations of a balance, but this is done at the cost of a similarly markedly increased complexity and complexity compared to a conventional one-spin balance.

Alternative solutions, more suited to the spatial constraints specific to the construction of a wristwatch, had also been disclosed. Indeed, US Patent 3,208,287, from a 1962 filing, describes an oscillator comprising a tuning fork coupled to an exhaust wheel through magnetic interactions. Specifically, the tuning fork carries permanent magnets cooperating with the exhaust wheel, the latter being made of a magnetically conductive material. The exhaust wheel is kinematically connected to a power source that can be mechanical or take the form of a motor, while it comprises openings, in its thickness, such as a variable magnetic form of magnetic re-glow when driven by rotating magnets, in relation to the rotating circuit of the tuning fork.

Therefore, a permanent interaction of substantial intensity takes place between the switch and the exhaust wheel, which can be described as a magnetic lock, such a construction consisting therefore of a non-free exhaust. The energy input from the switch to the switch to maintain its oscillations, even if small, is continuous and constitutes a source of considerable disturbance from the point of view of the isochronism of these oscillations.

Thus, the type of interaction involved in this construction is close to a contact, which is unfavourable from the point of view of the precision of the movement.

With the exception of the Louis-François-Clément Breguet clock, all these mechanisms use magnetic interaction and none of them can be used to make a purely mechanical watch, i.e. without electronics or magnetic interaction.

The Commission shall adopt implementing acts laying down the rules for the application of this Regulation.

A main purpose of the present invention is to overcome the disadvantages of the known tuning oscillators of the earlier art by proposing an oscillator for a mechanical watchpiece, especially for a wristwatch, with a high quality factor and isochronism and a free-type escapement.

When a tuning-pipe resonator is used in a watch with a free exhaust, particularly in a wristwatch, a number of technical problems arise.

The frequency of oscillations of a tuning fork is much higher than that of a coil swing. For example, the Accutron mentioned earlier has its tuning fork vibrating at a frequency of 360 Hz, compared to the 4 Hz of the coil swing of most mechanical watches today. Thus, adapting a conventional free-flow exhaust to operate in relation to a tuning fork is not obvious.

The amplitude of vibration of a watch tuner is small. For example, the amplitude of vibration of the Accutron tuner is 0.036 mm, compared to the amplitude of oscillations of the pendulum in a spiral swing system, which is about 2 mm.

Such a low amplitude makes the exhaust components more difficult to make than in the case of a spiral swing.

In addition, the higher operating frequency and the reduced amplitude imply that the corresponding exhaust should act on a larger portion of the swing of the tuning fork and the disruption due to the exhaust should therefore be greater than in the conventional case.

An additional problem is that the oscillatory motion of the blades or branches of the tuning fork is almost linear, compared to the circular motion of the swing.

This linear movement requires changes to the exhaust components, since, in particular, the issue of the inputs and outputs of an ankle in an anchor fork becomes problematic.

In addition, it should be noted that the lateral amplitude of the oscillations of a tuning fork, i.e. following a direction appreciably perpendicular to the direction of the fork, is likely to vary greatly, up to 50% compared to an average value according to Max Hetzel.

Finally, it should be noted that the use of a dial in a wristwatch poses a problem in terms of space, since the dial used in the Accutron model has a length of 25 mm, compared with the normal diameter of a pendulum, which is about 10 mm.

After verifying the feasibility of an oscillator of the type mentioned above in terms of operating frequency and energy consumption, the Applicant set out to solve the problem of designing an oscillator to take into account the small amplitude of the oscillations of the branches of a tuning fork.

The calculations made by the Applicant led to the conclusion that, for example, a 50 Hz vibrating tuner with a vibration amplitude of 0,07 mm has a similar level of energy consumption to that of a conventional coil balancer.

In order to answer the general technical problem mentioned above, it has been shown that the present invention relates in particular to an oscillator of the type described above, characterized by the fact that it has a single conversion organ of the first pin and is arranged to: On the one hand, to transform the oscillations of the first branch of the resonator into rotational motions of the anchor by transmitting first pulses to the latter, and,on the other hand, to transmit mechanical energy from the anchor to the first branch of the resonator in the form of pulses,so that the first tooth has an axial displacement amplitude,i.e. substantially following the direction of the first axis, when the anchor is pivoted, which is greater than the displacement amplitude of the first ankle substantially following the direction of the first axis.

It is clear from the above geometrical considerations that, in the conventional resonator-anchor-exhaust system, the plate-mounted ankle, which is in conjunction with the resonator and operates the anchor to release the exhaust wheel, has an axial displacement amplitude, considering here that the axis of the anchor when oriented towards the axis of the balance is greater than that of the anchor.

The present invention also provides that the amplitude of axial displacement of the teeth of the anchor fork is greater than that of the ankle, a conversion organ being provided to ensure proper cooperation between these elements and, finally, to allow the proper functioning of a free exhaust.

The conversion organ can be made in various forms without going beyond the scope of the present invention.

In the first case, it may be expected that the pendulum will have a swing, which is to be mounted pivoting on a structural element of the movement and, in conjunction with the first pendulum so that it can pivot in relation to the first branch of the resonator, the pendulum will have a second pendulum which is to cooperate with the first tooth and with a second fork tooth to rotate the anchor.

In a preferred alternative embodiment, it consists of a support arranged on the first branch of the resonator and bearing the first and second pegs, which are intended to cooperate alternately with the first and second forked teeth respectively and are located at a relative distance slightly less than the relative distance between the first and second forked teeth.

The present invention makes it possible to implement a mechanical oscillator for a watch part with a tuning fork and a free exhaust.

The advantage is that the anchor has a barrel with first and second arms bearing the first and second forks, respectively.

According to a preferred variant, the anchor is joined by an anchor rod to ensure its mounting on the movement, the first and second arms extending significantly from the anchor rod.

Several variants of construction can be considered, depending on the constraints to be met in terms of the volume in particular. e.g. the anchor comprises additional first and second arms intended to cooperate alternately with the exhaust wheel, these first and second arms on the one hand, and the first and second additional arms on the other hand, all of which can be arranged either in one plane or in two separate planes.

In addition, it can also be expected that the oscillator will include a second exhaust wheel, arranged to cooperate with either the same anchor or with an additional anchor arranged to cooperate with the second branch of the resonator.

Brief description of the drawings

Other features and advantages of the present invention will be more clearly seen by reading the following detailed description of preferred embodiments, made with reference to the attached drawings given as non-limiting examples, in which: Figures 1a and 1b represent diagrams of the stresses to be taken into account in the implementation of the present invention;Figure 2 represents a schematic face view of a mechanical oscillator for clock movements according to a first embodiment of the present invention;Figure 3 represents a schematic face view of a mechanical oscillator for clock movements according to a first embodiment of the oscillator in Figure 2;Figure 4 represents a schematic face view of a mechanical oscillator for clock movements according to a second embodiment of the oscillator in Figure 2;Figure 5 represents a schematic face view of a mechanical oscillator for clock movements according to a third embodiment of the oscillator in Figure 2;Figure 6 represents a schematic face view of a mechanical oscillator for clock movements according to a third embodiment of the oscillator in Figure 2;6b, 6c, 6d and 6e represent views of a functional detail of the oscillator in Figure 2 in successive configurations, and Figure 7 represents a schematic face view of a mechanical oscillator for clock movements according to a second embodiment of the present invention.

Method (s) of realization of the invention

Figures 1a and 1b represent illustrative diagrams of the stresses to be considered in the implementation of the present invention, more precisely in terms of the geometry to be observed, to ensure good cooperation between a tuning fork and an exhaust anchor fork.

Figure 1a shows the displacement of an anchor, radius R, to assess the relationship between the angle of rotation it takes between the first and second rays and the displacement of its end following the direction of the second ray, i.e. significantly in the axis of the switch branch.

Bold lines 201 and 202 illustrate the first and second positions that the anchor can take when it turns in response to a pulse transmitted by a tuning fork, shown by fine lines 203 and 204.

Specifically, when the anchor is in the 201-line position, the tuning fork (line 203) must be able to pass in front of one of its front teeth without touching it, while when it is in the 202-line position it must be able to transmit a pulse to the tuning fork (line 204) through the other tooth of its fork to maintain the oscillations of the tuning fork.

The axial displacement of the end of the anchor, i.e. following the direction of the branch of the tuning fork, is given by:

It is clear that the axial displacement of the anchor is one order of magnitude smaller than its angle of rotation.

For the usual order of magnitude of an anchor with a conventional shape, i.e. parallel teeth and a length of about 2.1 mm, the anchor having a pivot of 5 degrees, the above formula gives an axial displacement of its end of about 0.008 mm, or less than one hundredth of a millimeter.

In general, the release phase is approximately 2 degrees of pivot of the anchor. Thus, when the branch of the diaphragm leaves a first tooth of the fork after pushing it, there are 3 degrees of pivot left at the anchor during which the other tooth must have sufficient axial displacement to transmit a pulse to the branch of the diaphragm. This angle of 3 degrees corresponds to an axial displacement of 0.005 mm.

Considering the case of a conventional flat-bed ankle, with a lift phase representing a 30 degree angle, the lift begins at an angle of the order of 15 degrees and ends at an angle of the order of 9 degrees. In this case, the axial displacement of the ankle is usually in the order of 0.046 mm (for a 0.7 mm radius of the ankle trajectory), which gives a relative axial displacement of the order of 0.05 mm between the ankle and the corresponding fork tooth of the anchor.

If the overlap between the tooth and the ankle is assumed to be about 0.025 mm at the end of clearance, 0.025 mm of clearance remains between the tooth and the ankle to allow the latter to enter the range.

For this reason the fork has a well-defined width, to facilitate the entry of the ankle.

Figure 1b shows a schematic of the shift of a width range 2S.

The 2S width of the fork facilitates the entry of the ankle into the fork by contributing to the axial displacement mentioned earlier, since it is of the same order as the angle a: a rotation of an angle a of a horizontal arm of length S gives a vertical displacement of -S.sin(a) being approximately -S.a. So if the fork has a height R, following the axial direction, and the wall of each of its teeth is at a distance S from the axis then, for a small rotation of angle a, the axial displacement due to R is approximately R.a2 and the displacement due to S is approximately S.a.

For example, by positioning a fork wall 0.25 mm from its anchor axis (the usual order of magnitude for a conventional swing exhaust), the axial displacement of the wall is increased by 0.25. (sin((5°) -sin(3°)) or about 0.009, which increases the cross-sectional dimension from 0.025 mm to 0.03 mm.

For the treble, the situation is more complex because the movement of its branch or blade is almost linear, while with the swing the treble's ankle has a rotational movement.

For example, for a vertical branch of length R vibrating at an amplitude A, the vertical displacement is which is the same calculation if the angle of rotation of the branch is a=arctan ((A/R) or about A/R.

For example, for the Accutron with branches 20 mm long, but only 2/3 of which are in apparent circular motion, and an amplitude of 0.036 mm, the vertical displacement is - 0.00005 mm, so imperceptible for the application in question.

Similarly, for a 20 mm long tuning fork with a width of 0.07 mm and a 2.1 mm anchor with a clearance of 1 degree to 0 degrees, the above calculations lead to a vertical displacement of the tuning fork branch of 0.0001 mm and a vertical displacement of the anchor of 0.0003 mm, i.e. a difference of 0.0004 mm, which is not acceptable.

A wider fork should therefore be considered to allow the ankle to fit in.

Consider, for example, a fork whose walls are at a distance S from the anchor's axis. The displacement following a direction parallel to the axis between 1 degree and 0 degree is therefore S.sin(1°) or about 0.017.S. By laying S=2.5mm, this gives an axial displacement of 0.44mm. Furthermore, the ankle on the tuning fork also rotates at a certain angle.

So for this basic example, the fork should have walls at least 2.5mm apart in relation to the anchor axis, for a total length of 5mm.

These calculations are based on the assumption that the vibrations of the diaphragm are approximately circular. In reality, the movement is more complex and one should refer to the exact behavior of a bending deformed bar for more precision. The calculations presented here are given for guidance purposes so in practice the exact geometry of the range will have to be adapted to the exact trajectory of the vibrations of the diaphragm.

The above considerations led the Applicant to revise the geometry of the fork and, consequently, that of the conventional tray.

Figure 2 shows a schematic front view of a mechanical oscillator for a watch movement in a first embodiment of the present invention.

This oscillator has a resonator 1 of a tuning fork type, here noticeably U-shaped in a non-limiting way, whose base 2 is intended to be made solid with a building element of a watch movement (not illustrated for clarity) to allow branches 3 and 4 to vibrate in reference to the base, in a known way.

Alternatively, the tuning fork may have a different shape, such as, and preferably, a shape similar to that described and illustrated in US Patent 3,447,311.

As mentioned above, the amplitude of the tuning fork vibrations is very low and would not be suitable for the construction of a conventional oscillator, simply replacing the spiral swing system with a tuning fork.

The Applicant has also carried out research to develop a mechanical tuning oscillator for clock movements with a conversion organ arranged to: On the one hand, to transform the movements of a tuning fork into rotational movements of an anchor by transmitting first pulses to it, and, on the other hand, to transmit mechanical energy from the anchor to the tuning fork in the form of pulses, so that the teeth of the anchor fork have an axial displacement amplitude, i.e. substantially following the direction of the axis of the tuning fork, when the anchor is pivoted, which is substantially greater than the amplitude of displacement of the end of the tuning fork following its axial direction.

Figure 2 shows an example of an oscillator made in an illustrative manner.

The free end 5 of a first branch 3 of the tuning fork is fitted with a support 6 supporting the first and second pegs 7 and 8 serving as the tread in a conventional system, as will be shown in the detailed description in Figures 6a to 6.

The support 6 is elongated in shape, following a direction which is approximately perpendicular to the direction of the first branch 3, being fixed to the latter by its middle, the pegs 7, 8 being arranged at its respective ends.

The ankles 7, 8 cooperate with an anchor 10, specifically with first and second teeth 11 and 12 of the anchor defining an anchor fork.

Anchor 10 comprises a barrel designed to be mounted on a clockwork barrel by means of an anchor rod 14. The barrel has first and second arms 15, 16 extending from the anchor rod and each of which carries one of the teeth 11, 12 at its free end.

The hull also has additional first and second arms 18, 19 also extending from the anchor rod 14 and bearing first and second pallets 21, 22 respectively arranged to cooperate with the gear of an exhaust wheel 24 in a considerably conventional manner. Thus, anchor 10 is designed to rotate between a first position in which one of its pallets 21, 22 locks the rotating exhaust wheel 24 and a second position in which the other pallet locks the exhaust wheel. When the anchor pivots between one and the other position, the exhaust wheel is released to rotate.

The distance between the 7th and 8th pegs is slightly less than the distance between the 11th and 12th teeth to ensure proper oscillator operation.

It is shown in Figure 2 that the oscillator of the present invention provides a similar operation to that of conventional oscillators, in particular by the fact that the resonator carries two pegs 7 and 8 instead of a single peg, and by the particular geometry of the anchor fork. The solution illustrated for non-limiting purposes not only ensures that the anchor has a sufficient rotational range for proper cooperation with the exhaust wheel, but also ensures that the pegs 7 and 8 can take turns entering the fork and pulling the anchor in an appropriate manner, and can also exit it in a symmetrical manner.

Of course, the skilled person can adjust the number of teeth of the exhaust wheel or the lever arms between the different arms of the anchor according to his own needs and without going beyond the scope of the present invention.

In particular, it should be noted that the lever arm of the anchor can be modified by changing the distances between the anchor rod and the teeth of the fork on the one hand and between the anchor rod and the pallets on the other hand to adapt the geometry of the anchor to the needs.

In addition, it should also be noted that a reduction in the lever arm of the fork makes it easier to build the exhaust, since it increases the resting surface area of the pallet and the width of the pallet. The increase in the angle of rotation of the anchor increases the displacement of the fork following the axial direction of the anchor, which facilitates the entry and exit of the peg (s). The width of the fork can thus be reduced.

It should be noted that in the embodiment shown in Figure 2 the first and second arms 15, 16 of the anchor and its first and second additional arms 18, 19 are all in the same plane.

Figure 3 shows a schematic front view of a mechanical oscillator for watch movements in a first version of the oscillator shown in Figure 2.

The same numerical references as in Figure 2 will be used to simplify the understanding of Figure 3.

The oscillator is broadly the same as in Figure 2 except that the first and second additional arms 18, 19 of anchor 10 extend into a second plane different from that containing the first and second arms 15, 16.

These features allow the exhaust wheel to be arranged in a different plane from the diaphragm and at a smaller distance from it than in the case of Figure 2.

This configuration reduces the volume of the control-exhaust assembly and is better suited for integration into a wristwatch.

The man of the trade will have no particular difficulty in changing the shape of the anchor to suit his own constraints in terms of volume.

Figure 4 shows a schematic front view of a mechanical oscillator for clock movements according to a second variant of the oscillator in Figure 2. According to this variant, the mediators of the first and second arms 15, 16 on the one hand and the first and second additional arms 18, 19 on the other hand have an angle of about 120 degrees to each other.

Figure 5 shows a schematic front view of a mechanical oscillator for clock movements according to a third variant of the oscillator in Figure 2. According to this variant, the mediators of the first and second arms 15, 16 on the one hand and the first and second additional arms 18, 19 on the other hand have an angle of about 180 degrees to each other.

It is shown in Figures 4 and 5 that the exhaust wheel and the diaphragm may possibly be at least partially overlapped, in particular to reduce the congestion of the exhaust diaphragm assembly as mentioned above.

Figures 6a, 6b, 6c, 6d and 6e show a detailed view of the oscillator operation in Figure 2 in successive configurations over a half-alternation of the oscillations of the first branch 3.

Starting from Figure 6a, the first branch 3 of the tuning fork finishes its run following the direction of the arrow, to the left of the figure, just before it starts again in the opposite direction.

In this situation, the first pad 21 of anchor 10 cooperates with the gear of the exhaust wheel 24 to lock the latter in rotation.

When the branch 3 turns to the right of the figure, as shown in Figure 6b, the second anchor tooth 12 is on the path of the second anchor 8. When contact is made between them, a release phase begins by rotating the anchor clockwise in Figure 6b, under the influence of the pulse transmitted by the second anchor.

During the clearance phase, the first tooth 11 rises back towards the first peg 7, as shown in Figure 6c.

A pulse phase from the anchor to the first peg 7 then takes place, as shown in Figure 6d, to ensure the maintenance of the oscillations of the first branch 3 of the tuning fork.

At the same time, the second pallet 22 is folded in the direction of the exhaust wheel 24 until it is locked again, as shown in Figure 6.

The second half-alternance then begins and the same phases occur again in the same chronological order, in the conventional way.

It is thus found that, for anchor 10 to cooperate effectively with the exhaust wheel 24, the greatest distance between the different positions of its teeth 11, 12 must be large, at least more than twice the amplitude of vibrations of the third branch of the tuning fork, which, as noted above, is small and insufficient on its own to move the anchor satisfactorily.

In the above figures, the oscillator of the invention has a conversion organ comprising two pegs 7,8 coupled to two teeth 11, 12 spaced to ensure sufficient rotation of the anchor.

However, it is possible to make the conversion organ in different forms without going beyond the scope of the present invention.

Figure 7 shows a schematic face view of a mechanical oscillator for clock movements in a second embodiment of the present invention, which gives a similar result.

The anchor 100 is more conventional in shape, with a width range 101 reduced from that shown in the previous figures.

The conversion device used in the present model thus uses the leverage principle.

It has a 110-pin swing designed to be mounted on a rotating part of the movement by means of a 111 pivot.

The swing comprises, at one end, a first pivoting pivot 112 mounted on the free end 5 of the first branch 3 of the tuning fork and, at a second end, a second pivot 113 engaged between the teeth of the fork 101 to cooperate with it and rotate the anchor 100 when the first branch 3 vibrates.

It is also noted that the maximum distance between the different positions of the teeth of the 101 fork is more than twice the amplitude of the vibrations of the 3rd branch of the tuning fork. However, the structure of the conversion organ allows for both a good transmission of pulses from the anchor to the tuning fork to maintain the oscillations of the latter and a good transmission of pulses from the tuning fork to the swing to rotate the latter with an amplitude that ensures the proper operation of the associated attachment.

Although this solution has a more complex construction and a faster wear of the components involved than in the first embodiment, it nevertheless makes it possible to produce a mechanical oscillator meeting the characteristics of the invention.

The above description is intended to describe particular embodiments by way of illustration, and the invention is not limited to the implementation of certain particular features which have been described, such as the specifically illustrated and described shape of the tuning fork, exhaust wheel or anchor.

It should be noted, for example, that because of their smaller size than in conventional systems, by about an order of magnitude, the shape of the pallets should be modified to strengthen them. In particular, the rectangular section of conventional pallets is fragile when their width decreases, so a trapezoidal section may be preferred. The thickness of the pallets can also be increased to strengthen them, in a complementary way.

It is also possible to increase the pull of the pallets by making them join the anchor arms at a certain angle, different from the usual right angle.

The professional will not have any particular difficulty in adapting the contents of this disclosure to his own needs and in implementing a mechanical oscillator other than that described herein, but including a conversion organ allowing the construction of a free-flow oscillator as described above, without going beyond the scope of the present invention. In particular, to ensure the proper operation of the oscillator according to the present invention, the conversion organ and the anchor are preferably arranged so that a lever arm is created between the diagonal pin and the exhaust wheel, in order to ensure sufficient amplitude for the oscillations of the anchor teeth.

It should also be noted, as mentioned above, that the invention is not limited to an oscillator with a single exhaust wheel or anchor, but a second exhaust wheel could be associated with the anchor or even an additional anchor cooperating with the second branch of the tuning fork.

Furthermore, it should be noted that the relative positioning constraints of the various components of the oscillator according to the present invention are strict, so that the professional can implement any known suitable means which he deems useful to optimise the realization of the invention, such as flexible rotating guides for the rotating components of the oscillator, particularly for the anchor.

Finally, it should be noted that the technology of manufacturing silicon compounds is particularly suitable for the production of the elements described, in particular because it ensures good precision of manufacture and the silicon elements in contact with each other have reduced friction compared to the materials commonly used in the watchmaking industry.

Claims (12)

1. A mechanical oscillator with tuning fork and detached escapement, for a mechanical clockwork movement, including a resonator (1) of the tuning fork type, whereof at least a first branch (3) is intended to oscillate on either side of a first axis and bears at least a first pin (7, 8, 112) associated with at least a first fork tooth of a pallet (10, 100) included by said oscillator, to cooperate directly or indirectly with it and to pivot said pallet (10, 100) between first and second angular positions and alternatingly lock and free an escapement wheel (24), said mechanical oscillator including a conversion organ (6, 110, 113) secured to said first pin and arranged to

   on the one hand, convert the oscillations of said first branch (3) of said resonator (1) into rotating movements of said pallet (10, 100) by transmitting first pulses to the latter, and

   on the other hand, transmit mechanical energy from said pallet (10, 100) to said first branch (3) of said resonator (1) in the form of pulses,

   such that said first tooth has an axial movement amplitude, substantially along the direction of said first axis, during the pivoting of said pallet, greater than the movement amplitude of said first pin substantially along the direction of said first axis.
2. The mechanical oscillator according to claim 1, characterized in that said conversion organ includes a lever (110), intended to be mounted pivoting on a frame element of the clockwork movement, and a first end of which is secured to said first pin (112) so as to be able to pivot in reference to said first branch (3) of said resonator (1), said lever bearing a second pin (113) intended to cooperate with said first tooth and with a second tooth of said fork (101) to pivot said pallet (100).
3. The mechanical oscillator according to claim 1, characterized in that said conversion organ includes a support (6) arranged on said first branch (3) of said resonator (1) and bearing said first pin (7) and a second pin (8), the latter being intended to cooperate alternatingly and respectively with said first tooth and with a second fork tooth (11, 12) and being situated at a relative distance slightly smaller than the relative distance between said first and second fork teeth.
4. The mechanical oscillator according to claim 3, characterized in that said pallet (10) comprises a frame having first and second arms (15, 16) respectively bearing said first and second fork teeth (11, 12).
5. The mechanical oscillator according to claim 4, said pallet (10) being secured to a turning-arbor (14) intended to mount it on the clockwork movement, characterized in that said first and second arms (15, 16) extend substantially from said turning-arbor (14).
6. The mechanical oscillator according to claim 5, said pallet (10) comprising first and second additional arms (18, 19) intended to cooperate alternately with said escapement wheel (24), characterized in that said first and second arms (15, 16) as well as said first and second additional arms (18, 19) are all arranged in a same plane.
7. The mechanical oscillator according to claim 5, said pallet comprising first and second additional arms (18, 19) intended to cooperate alternately with said escapement wheel (24), characterized in that said first and second arms (15, 16), on the one hand, and said first and second additional arms (18, 19), on the other hand, are arranged in first and second separate respective planes.
8. The mechanical oscillator according to any one of the preceding claims, characterized in that it includes a second escapement wheel associated with said pallet (10).
9. The mechanical oscillator according to any one of the preceding claims, characterized in that it includes a second escapement wheel associated with an additional pallet arranged to cooperate with the second branch of said resonator.
10. The oscillator according to any one of the preceding claims, characterized in that said resonator and/or said pallet and/or said escapement wheel are made from silicon.
11. A clockwork movement including a mechanical oscillator according to any one of the preceding claims.
12. A timepiece including a clockwork movement according to claim 11.