EP3765919A1

EP3765919A1 - Timepiece display mechanism having a variable geometry and an elastic hand

Info

Publication number: EP3765919A1
Application number: EP19742224.9A
Authority: EP
Inventors: Marc Stranczl; Jan Pittet
Original assignee: Montres Breguet SA
Current assignee: Montres Breguet SA
Priority date: 2018-07-31
Filing date: 2019-07-24
Publication date: 2021-01-20
Anticipated expiration: 2039-07-24
Also published as: US20210026305A1; EP3765920A1; CN111902779B; US11841685B2; US20210373497A1; JP6977179B2; US20210373496A1; US11860577B2; JP2021015110A; JP2021515226A; EP3605244A1; US11841684B2; EP3765920B1; WO2020025424A1; US11774909B2; EP3764168A1; EP3830649A1; JP2021189165A; JP2021189163A; JP2021515889A

Abstract

Disclosed is a variable timepiece display mechanism (10) comprising an elastic hand (1) with a drive barrel (2) secured to a single-piece flexible blade (3) comprising flexible segments (5; 5A; 5B) adjoining at apexes (6), a first (5A) of said segments extending between the first barrel (2) and a first apex (6), the mechanism (10) further comprising drive means (11) for pivoting the barrel (2), and means (12) for stressing the first flexible segment (5) in order to vary the position of the first apex (6) relative to the output pin (D) according to the forces applied to the flexible blade (3), said drive means (11) and/or said stressing means (12) comprising a first gear train (111) having a particular shape and/or a second gear train (131) having a particular shape for accelerating, stabilizing the speed of, or decelerating at least the barrel (2) over part of its angular travel.

Description

P5763 / EG WO01 text for deposit VARIABLE GEOMETRY CLOCK DISPLAY MECHANISM WITH

ELASTIC NEEDLE

Area of invention

The invention relates to a clockwork display mechanism with variable geometry, comprising at least one elastic hand which comprises a first drive barrel secured to a first end of a flexible blade, and a second drive barrel secured from another end of said flexible blade, and which has a display apex or index which, in an unconstrained free state of said elastic needle in which both said first barrel and said second barrel are not subjected to any stress and are distant from each other, is distant from said first barrel and from said second barrel, the service position of said elastic needle being a constrained position where said first barrel and said second barrel are coaxial with each other around an output axis, said display mechanism comprising first means for driving said first barrel around said output axis, e t second means for driving said second barrel around said outlet axis, said first driving means and second driving means being arranged to deform said flexible blade, by varying the angular position of said second barrel relative to the position angular of said first barrel around said outlet axis, and to vary the radial position of said apex or display index relative to said outlet axis.

The invention also relates to a clockwork movement comprising at least one such display mechanism.

The invention also relates to a timepiece comprising at least one such clockwork movement, and / or comprising at least one such display mechanism.

The invention also relates to a scientific apparatus comprising at least one such clockwork movement, and / or comprising at least one such display mechanism.

The invention relates to the field of analog display mechanisms by moving mechanical components, for timepieces or scientific apparatus.

Invention background Documents EP2863274 and EP3159751 in the name of MONTRES BREGUET SA describe different arrangements of elastic hands, allowing the adaptation of a display on a timepiece to the shape of its case or its dial, thanks to a radial extension obtained by controlling such an elastic needle comprising distinctly driven flexible segments.

Summary of the invention

The invention proposes to provide a reliable and robust solution to the problem of providing a variable radial extension indicator according to its position and its control.

To this end, the invention relates to a clockwork display mechanism comprising at least one such elastic needle, which comprises a first drive barrel secured to at least one flexible blade, according to claim 1.

Brief description of the drawings

Other characteristics and advantages of the invention will appear on reading the detailed description which follows, with reference to the appended drawings, in which: FIG. 1 shows, schematically and in plan view, a watch, in particular a ladies' watch of oval shape, comprising a display mechanism according to the invention, comprising an elastic needle of variable length, the distal end of which, which is formed by an apex between two flexible blades, is arranged to travel a non-trajectory circular; this elastic needle is shown in a twelve o'clock position, in which the elastic needle has an almond shape, and where the apex is in its position furthest from an axis of exit;

Figure 2 shows, similarly to Figure 1, the same watch, in a position at six o'clock of the elastic needle which then has a shape of a heart, and where the apex is in its position closest to a output axis; Figure 3 shows, similarly to Figure 1, the same watch, in the same position and in the almond shape of the elastic needle, this view shows a trajectory of the apex which, relative to the axis of exit , is in elongation on a 120 ° angle from eight hours to twelve hours, and in shortening on another 120 ° angle from twelve hours to four hours; this same trajectory is substantially circular with respect to an eccentric circular axis, at an angle of approximately 240 °, from the eight o'clock position to the twelve o'clock position, and from the latter to the four o'clock position;

Figure 4 shows, similarly to Figure 2, the same watch, where the top of the needle is in the four o'clock position, and where the shape of this elastic needle is now a heart shape, after a change form intervened before this position at four o'clock;

Figure 5 shows, similarly to Figure 4, the same watch, where the top of the hand is in the eight o'clock position, and where its shape is always the same heart, the top has traveled, between representations in FIG. 4 and in FIG. 5, a circle here centered on the outlet axis, and before a new change of shape after this position at eight o'clock, to find the almond shape of FIG. 3;

FIG. 6 represents, schematically and in plan view, the elastic needle of FIGS. 1 to 5, in a constrained service position, where two end barrels which it comprises, at the ends of its two flexible blades, are aligned and superimposed on each other, each driven by a different mobile;

Figure 7 is a variant of Figure 6, where the top has an eye arranged to allow a particular display on a dial;

- Figure 8 shows, similarly to Figure 1, the same watch, in the same position and in an empty form, almond shaped, of the elastic needle, which is free, in an unstressed state, and fixed to a driving mobile by only one of its guns;

Figure 9 is a left view of the watch of Figure 8;

FIG. 10 represents, in a similar manner to FIG. 1, the same watch, in the same position and where the elastic needle comprises a breakable element connecting its two end barrels and facilitating its assembly on the clockwork movement, as well as the manipulation of the second barrel for its installation above the first, before the watchmaker ruptures fragile attachments connecting the breakable element to the two guns;

Figure 1 1 is a block diagram, in exploded perspective, of a display mechanism according to the invention, where a power take-off, in the lower part of the figure, is arranged to drive two gear trains, the first to drive the first gun, and the second to drive the second gun; the arrows illustrate the transmission of movement; the gear trains have shaped cogs, which are arranged to accelerate, stabilize, or slow down the rotation of one of the guns relative to the other; the elastic needle is shown in a completely free state, with no breakable element; this view also shows a conventional hand, coaxial with the elastic hand, for displaying other information, in particular time;

FIG. 12 is a perspective view of a display mechanism according to a variant of the invention, in which an input mobile, arranged to cooperate with a mobile output from the clock movement, is coaxial with a shaft drive, and a carriageway on which the first barrel is shown mounted, the second barrel being shown in the free state of the elastic needle before its positioning coaxial with the first barrel on the drive shaft; each form wheel has an angular marking so as to correctly ensure the form gear effect;

Figure 13, similar to Figure 12, illustrates the positioning of a cutting plane, according to which the cut of Figure 14 is carried out;

Figure 14 is a partial section along the plane viewed in Figure 13, of a clockwork movement driving a mechanism according to the invention;

- Figure 15 illustrates, in plan view, a gear train with two stages so as to balance the angular travel of each stage, and where each stage comprises a gear train;

FIG. 16 is a plan view of a display mechanism according to a variant of the invention, in which an input mobile, arranged to cooperate with a mobile output from the clock movement, is distinct from the output axis, and where each gear train comprises two stages so as to balance the angular travel of each stage, and where each stage comprises a form train; Figures 17 to 20 illustrate the construction of the cogs of form: FIG. 17 illustrates the choice of a space law for varying the radial length of the needle as a function of the angular difference between its two barrels, this figure illustrates the exit angle as a function of the angle d 'Entrance ;

FIG. 18 illustrates the calculation of the primitive profiles of the teeth, according to the spacing chosen for their realization;

FIG. 19 illustrates the calculation of the leading teeth, as a function of the number of teeth defined;

FIG. 20 illustrates the calculation of the gear teeth, which then allows the cutting of the two wheels with the profile thus defined;

- Figure 21, similar to Figure 17 but reversed, illustrates three successive zones of radial extension of the needle, stabilization of the length of the needle, and shortening of the needle;

FIG. 22 is a plan view of the superposition of the three states illustrated by FIGS. 3 to 5, and the arrows highlight a phase of contraction CO of the needle between the positions at twelve o'clock and at four o'clock summit, a stability phase ST with constant elongation between the four o'clock and eight o'clock positions, and a relaxation phase DE between the eight o'clock and twelve o'clock positions;

FIG. 23 is a diagram showing on the ordinate the evolution of the torque between the flexible segments of the elastic needle, as a function of the angle covered, with a first zone for reducing the length of the elastic needle with consumption of torque, a second phase of maintaining the length of the needle at substantially constant torque, and a third phase of lengthening the needle with restitution of the torque;

- Figure 24 is a diagram showing on the ordinate the evolution of the torque on a barrel, as a function of the angle of rotation of a barrel;

FIG. 25 is a diagram showing on the ordinate the radial extension of the needle, as a function of the angle of rotation of a barrel;

FIG. 26 represents, in plan view, a cog in shape comprising two non-revolution wheels, and comprising marks for their relative indexing with respect to one another;

FIG. 27 represents such a wheel, with an involute toothing, enlarged in magnifying glass; FIG. 28 represents such a wheel, with sinus toothing, enlarged in magnifying glass;

FIG. 29 illustrates, in exploded perspective, a display mechanism according to the invention, limited to the barrels of the elastic needle which is not shown; this mechanism includes two differentials carried by a mobile planet carrier chassis between two fixed flanges carrying differential input cams, and the assembly thus represented constitutes an additional block adaptable to an existing movement; the two barrels of the elastic needle are here coaxial around a roadway arranged to constitute an outlet for such a movement.

Detailed description of preferred embodiments

The invention relates to a display indicator for a timepiece or for a scientific device.

Documents EP2863274 and EP3159751 in the name of MONTRES BREGUET SA describe a horological display by elastic needle, and their characteristics can be directly used for the production of a display mechanism according to the present.

The invention is described here in the particular, but not limiting, case of a rotary indicator, and in particular of an elastic needle. However, the principle is applicable to an indicator with a mobility path other than circular, for example a linear cursor, or other, in particular in space. The invention is more precisely described for this application of a flexible indicator to a needle, but it is applicable to other forms of indicators, in plan or even in three dimensions.

Similarly, drive means comprising cogs are described below, but the invention is equally applicable to analog display means for an electronic or electric device, a quartz watch or the like.

The principle of the invention is to provide a display mechanism, of which at least one indicator, in particular a hand, for example the minute hand for a watch, has a variable length, or a variable radial extension, or a shape variable.

The invention relates to a clockwork display mechanism 10 with variable geometry, which comprises at least one elastic needle 1. This elastic needle 1 comprises a first drive barrel 2, which is integral with at least one blade flexible 3 piece, and a flexible blade 3 unique in the particular case and not limiting of the figures.

The display mechanism 10 comprises an input mobile 71, which is arranged to be pivotally driven about an input axis by a movement 20, and which defines an input angle relative to a reference direction .

The elastic needle 1 comprises a first drive barrel 2 secured to a first end of a flexible blade 3, and a second drive barrel 4 secured to another end of this flexible blade 3, and the needle elastic 1 has a vertex or display index which, in an unconstrained free state of this elastic needle 1 in which both the first barrel 2 and the second barrel 4 are not subjected to any stress and are distant from one the other, is distant from the first barrel 2 and the second barrel 4. The service position of this elastic needle 1 is a constrained position where the first barrel 2 and the second barrel 4 are coaxial with each other around 'an output axis D.

The display mechanism 10 comprises first drive means 1 1 of the first barrel 2 around the outlet axis D, and second drive means 13 of the second barrel 4 around this outlet axis D.

These first drive means 11 and second drive means 13 are arranged to deform the flexible blade 3, by varying the angular position of the second barrel 4 relative to the angular position of the first barrel 2 around the outlet axis. D, and to vary the radial position of the vertex or of the display index relative to the output axis D.

In a particular embodiment, the elastic needle 1, and more particularly its flexible blade 3, comprises a plurality of flexible segments 5, 5A, 5B, which are joined end to end at the level of at least one vertex 6, arranged to constitute such an index, and preferably two successive flexible segments are joined by such a vertex.

In the case of the figures, a first flexible segment 5A of the flexible blade 3 extends between the first barrel 2 and a first vertex 6.

More particularly the invention is illustrated in the most common case where the needle comprises two flexible segments 5 joined by a single apex 6, which is used for display. The display mechanism 10 includes first drive means 1 1 of the first barrel 2 around an outlet axis D, and includes second means 12 for stressing at least the first flexible segment 5: these second means 12 are arranged to vary the position of at least the first vertex 6 relative to the outlet axis D. The first vertex 6 is thus at a variable distance from the first barrel 2, according to the forces applied to the blade flexible 3 by the second means 12 for stressing.

Figures 1 to 5 show a particular case of such a mechanism, with an elastic needle 1 having a single apex 6, which follows on an upper part of its travel an eccentric circle relative to the outlet axis, and above a lower part of its travel another circle centered on the exit axis. Naturally, this is a special case, and the mechanism 10, for the same ove-shaped watch, can also be dimensioned to follow the outline of the case, or any other outline highlighting the product.

According to the invention, the first drive means 11 and / or the second means 12 for stressing, and in particular the second drive means 13 which they comprise, comprise a first gear train of form 111 and / or respectively a second formed gear train 131, which is arranged or which are arranged to accelerate or stabilize in speed or slow down at least the first cannon 2, and / or the second cannon 4, over part of its angular travel.

More particularly, the first drive means 11 and the second means 12 for putting under stress, and in particular the second drive means 13 which they comprise, comprise at least one first gear train of shape 11 and respectively at least one second deformation train 131 which are arranged to accelerate or stabilize in speed or slow down the first gun 2, and respectively the second gun 4, over at least part of the angular travel of the first gun 2, and respectively of the second gun 4 ..

In a particular embodiment, illustrated by FIGS. 1 to 5, the first drive means 11 and the second stressing means 12 are arranged to drive the elastic needle 1 over its entire angular travel around the output axis D, and give it, in projection on a display plane P or on a dial, and at different angular positions of the elastic needle 1, at least a first form where the flexible segments 5: 5A, 5B, that the flexible blade 3 does not cross apart from the first barrel 2, and at least one second form where the flexible segments 5: 5A, 5B, which comprises the flexible blade 3 intersect outside the first barrel 2. In the particular and nonlimiting case illustrated by the figures, this first form is an almond shape, and this second form is a form of heart. In another variant where the elastic needle 1 traverses the surface defined by an ellipse, this needle can successively occupy, on its revolution, an alternation of first shapes and second shapes, for example an almond shape on each of the two ends of the major axis of the ellipse, and a heart shape on each of the two ends of the minor axis of the ellipse.

More particularly, and as taught by documents EP2863274 and

EP3159751 the elastic needle 1 comprises a second drive barrel 4 also integral with the flexible blade 3. The second means 12 for stressing then comprise second drive means 13 for the second barrel 4 in a mounted and constrained state the elastic needle 1. In this mounted state of the elastic needle, both the first barrel 2 is, advantageously but not necessarily in a prestressed operating state, driven by the first drive means 1 1, and the second barrel 4 is, advantageously but not necessarily in a prestressed operating state, driven by the second drive means 13. And at least one of the vertices 6 is, in an unconstrained free state of the elastic needle 1 in which at the times the first cannon 2 and the second cannon 4 are not subjected to any constraint, distant from the first cannon 2 and the second cannon 4, which first cano n 2 and second barrel 4 are spaced from one another in this free state of the elastic needle 1.

In the particular case of the figures where the flexible blade 3 has only a first flexible segment 5A and a second flexible segment 5B, this vertex 6 which joins them is unique. Thus, more particularly, this first flexible segment 5A carries the first barrel 2 at a first end 52, this second flexible segment 5B joined to the first flexible segment 5A carries the second barrel 4 at a second end 54. And, in the free state of the elastic needle 1, the first end 52 and the second end 54 are spaced from each other, or form a non-zero angle with each other from the apex 6 of junction of the first flexible segment 5A and the second flexible segment 5B.

More particularly, the output of the second drive means 13 of the second barrel 4 is coaxial with the output of the first drive means 11 of the first barrel 2, in the mounted state of the elastic needle 1. However, this arrangement is not compulsory, in particular in the case of a retrograde display, where the axes of the first barrel 2 and of the second barrel 4 can be distinct.

According to the invention, the first drive means 1 1 and the second drive means 13 comprise an accelerator or retarder device, which is arranged to accelerate or stabilize in speed or slow down at least the first gun 2 and / or said second barrel 4 over at least part of its angular travel.

In a variant, the first gun 2 has an advance or a delay with respect to the value of the entry angle which is symmetrical with the delay or advance of the second gun 4 with respect to the entry angle, so that the first vertex 6 always displays, with respect to the exit axis D and to the reference, an angle equal to the entry angle.

In another variant, the first gun 2 has an advance or a delay with respect to the value of the angle of entry which is, in absolute value, different from the delay or the advance of the second gun 4 with respect to the entry angle, so that the first vertex 6 displays, relative to the exit axis D and to the reference, a variable angle relative to the entry angle throughout its travel. This particular advance and / or delay arrangement relative to the entry barrel allows the hand to point the time (or another display) just on the dial, and in particular for an irregular display, for example a square trajectory. where the time is separated into twelve equidistant segments on the square trajectory, which cannot be managed in the same way as twelve indexes separated by 30 °.

In yet another variant, the needle 1 is arranged to perform a non-retrograde total stroke, and, over the total stroke, the average speed of the first barrel 2 is equal to the average speed of said second barrel 4.

Many configurations can be considered:

- if the arms of the needle are symmetrical, a symmetrical advance and delay are necessary, so that the needle points to the correct hour;

- if the arms of the needle are asymmetrical, there must be an advance and a delay so that the needle points at the right time;

- we assume that the hand points the correct time. One can also have a graduation which is not separated every 30 ° as explained above. In a particular embodiment which will be detailed below, the accelerator or retarder device comprises a first train of form 11 and / or respectively a second train of form 131.

In another particular embodiment which will be detailed below, the accelerator or retarder device comprises a device with a first differential 912 on the drive train of the first gun 2 and / or a second differential 914 on the drive train of the second gun, and at least one cam 902, 904, constituting an input of such a differential 912, 914.

In yet another embodiment, the accelerator or retarder device comprises simple cogs suitably arranged to carry out the required accelerations or decelerations.

More particularly, and as visible in FIGS. 1 1 to 20, the first drive means 11 and the second drive means 13 comprise, Respectively, at least one first gear train of form 11 1 and at least one second gear train form 131, which are each arranged or which are arranged to accelerate or stabilize in speed or slow down the first barrel 2 and respectively the second barrel 4 over part of its angular travel. By gear train here we mean that at least one wheel of the train is not of revolution; more particularly, at least two antagonistic wheels of this cog are not of revolution, and are arranged to permanently mesh with minimal play with each other at constant center distance.

More particularly, the first gear train 11 1 and the second gear train 131 are arranged to accelerate or respectively brake the first gun 2, and to brake or respectively accelerate the second gun 4 over at least part of the angular travel of the elastic needle 1, or even only over part of the angular travel of the elastic needle 1. Stated otherwise, one of the barrels takes an angular advance with respect to the entry angle, while the other barrel takes a angular delay relative to the entry angle.

Thus, in a particular embodiment of the invention, the first gun 2 has an advance or a delay with respect to the value of said entry angle which is symmetrical with the delay or advance of the second cannon 4 with respect to this same entry angle, so that the first vertex 6 always displays, with respect to the exit axis D and to the reference direction, an angle equal to the entry angle. Thus, considering the embodiment according to FIGS. 3 to 5, with a total angular stroke CAT of 360 °, from a position in FIG. 3 where the apex 6 of the needle 1 is at twelve o'clock, to pass into the position at four hours of FIG. 4, by turning clockwise, the second gun 4 of the second flexible segment 5B has slowed down by 60 °, and the first gun 2 of the first flexible segment 5A has accelerated by 60 °. Indeed, none of the flexible segments 5 of the hand 1 indicates, only, the time, it is only the result of the rotation of the two barrels which determines a time indication by the top 6 of the hand 1. Between the position of Figure 4 and the eight o'clock position of Figure 5, the barrels remain synchronous with their offset. To go from the eight o'clock position in Figure 5 to the twelve o'clock position in Figure 3, it is the opposite, the second gun 4 of the second flexible segment 5B accelerated by 60 °, and the first gun 2 of the first flexible segment 5A has slowed down by 60 °.

The invention is illustrated in the figures by the particular case of a continuous watch display displaying a full revolution, it is understood that the invention is applicable to any display, in particular a retrograde display.

According to the invention, the first gear train 111 and the second gear train 131 are arranged to symmetrically pilot the first barrel 2 and the second barrel 4, so that the first flexible segment 5A and the second flexible segment 5B are symmetrical with respect to a radial coming from the outlet axis D and passing through the apex 6 of junction between the first flexible segment 5A and the second flexible segment 5B, over at least part of the angular travel of the elastic needle 1 This configuration is not limiting, but it offers the advantage of subjecting the first flexible segment 5A and the second flexible segment 5B to symmetrical constraints.

More particularly, the first gear train 11 1 and the second gear train 131 each comprise at least one pair of wheels arranged to cooperate in meshing with one another and whose geometric supports, that is to say -to say the primitive curves, teeth are not of revolution.

More particularly still, the first drive means 1 1 and / or the second drive means 13 comprise at least a first gear train 1 15, 135, and a second gear train 116, 136, which are arranged to control each part of the shape transformation of the elastic needle 1 over at least part of its angular travel, with a weighting per floor. This weighting makes it possible to distribute part of the deformation on each of the stages, which makes it possible, in each gear train, to keep wheels whose geometry is close to a circular geometry, so as to allow a suitable meshing of the teeth, and prevent their wear. Indeed, the cogs of shape are not circular, but must not be too deformed, that is to say that their shape must allow an engagement without bracing, and without too much sensitivity to variations in center distance and to manufacturing tolerances. It is thus possible to avoid the interference defects that would be caused by cut teeth if the primitive curves of the teeth were too far from the circular shape. It is therefore a question of defining a compromise between a shape that is sufficiently non-circular to actuate the needle, and a shape that resists use. The distribution over several stages makes it possible to fulfill these conditions: each stage participates in the deformation of the needle, but its primitive curves remain close to a circular shape, this is what is called here the weighting by stage, the overall accumulation of these stepped cogs to ensure the desired deformation at the needle.

The figures illustrate, without limitation, a variant with two stages of cogs, but this number of two is not limiting, only the total thickness of the movement and the loss of efficiency due to friction limit the number of stages.

More particularly, both the first gear train 115, 135, and the second gear train 116, 136, respectively comprise a first gear train 11 1 and a second gear train 131.

Figures 11 to 20 detail some specific arrangements of such cogs in shape.

FIG. 11 diagrams the operation of such a mechanism 10, the arrows symbolize the transmission of the movement to the barrels, from a power take-off 21 at the level of a clockwork movement 20, which can be both mechanical and electronic, symbolized in the lower part of the figure, and which is arranged to drive two gear trains by the same input mobile 71: - a first gear train comprises idler wheels 79 and 80 around a first axis DA and wheels 73, 78, and 81 around the main pivot axis D to drive the first barrel 2, and a second gear train comprises idler wheels 74, 75 around a second axis DB and a wheel 76 around the main pivot axis D to drive the second barrel 4.

It is noted that all of the gear train is under tension, owing to the play of the elastic needle due to its preload.

FIG. 11 shows, again, a conventional needle 101, coaxial with the elastic needle 1, for the display of other information, in particular time.

FIGS. 12 to 14 illustrate more precisely a display mechanism 10 according to a variant of the invention, for displaying the minutes with the elastic hand 1. In this variant, an input mobile 71 is arranged to cooperate with an output mobile 21 of the clockwork movement 20, along an input axis D0, and is guided on a fixed tube 70. This input mobile 71, which is a roadway, is arranged to drive, directly or through a friction lantern allowing a time-setting adjustment, a driving road 72 which is coaxial with it.

This driving pavement 72 is of revolution, and drives a first wheel of shape 78, which meshes with a second wheel of complementary shape 79 mounted madly (with backlash) around the first axis DA, and which is pivotally attached to a third wheel of shape 80, which meshes with a fourth idler wheel of complementary shape 81, which here pivots around the outlet axis D of the barrels, and which comprises a carriageway 82 for fixing the first barrel 2.

The same driving pavement 72 drives a fifth wheel of shape 73, which meshes with a sixth wheel of complementary shape 74 mounted madly around the second axis DB, and which is pivotally attached to a seventh wheel of shape 75, which meshes with a eighth idler wheel of complementary shape 76, which here pivots around the axis of exit D of the barrels, and is integral with a shaft 77 on which the second barrel 4 is fixed.

Each form wheel has an angular marking so as to correctly index the form cog, as detailed in FIG. 26 which details a form cog comprising two wheels75 and 76 not of revolution, and comprising marks 275 and 276 for their relative indexing with respect to each other, as well as oblongs 175 and 176 facilitating their positioning, which in particular makes it possible to join them together and to index them by means of a pin or the like. The driving pavement 72 also drives a ninth wheel 91 which has a mobile pivoting about an hour axis DH, which comprises a pinion 92 driving the wheel 93 of an hour pavement 94 receiving the hour hand 100.

FIGS. 15 and 16 illustrate a variant of the invention, in which an input mobile, arranged to cooperate with an output mobile from the clock movement, pivots about an input axis D0 which is here distinct from the output axis D, and where each gear train comprises two stages so as to balance the angular travel of each stage, and where each stage comprises a form train: - a first train train comprises a first stage with a first shaped wheel 101 pivoting around the input axis D0, which meshes with a second complementary shaped wheel 102, mounted idly around a first secondary axis D1. This second wheel of complementary shape 102 is pivotally attached to a third wheel of shape 103, which meshes with a fourth wheel of complementary shape 104, pivotally mounted on the output axis D, and designed for fixing one of the two cannons;

a second gear train, isolated in FIG. 16, comprises a first stage with a first wheel of shape 201 pivoting around the entry axis D0, which meshes with a second wheel of complementary shape 202, mounted madly around a second secondary axis D2. This second wheel of complementary shape 202 is pivotally attached to a third wheel of shape 203, which meshes with a fourth wheel of complementary shape 204, pivotally mounted on the output axis D, and designed for fixing the other gun.

The case of a construction with radial symmetry of movement between the two flexible segments of the same such needle 1 uses two similar sets of cogs of identical shape, one mounted upright, the other upside down.

Figures 17 to 20 illustrate the construction of the cogs, which begins with the choice of a space law to vary the radial length of the needle according to the angular difference between its two barrels, Figure 17 illustrates the exit angle as a function of the entry angle for one of the two needle barrels. This law of space allows the calculation of the primitive profiles of the teeth, according to the spacing chosen for their realization, as visible in FIG. 18. The calculation of the leading teeth is then carried out according to the number of teeth defined, and the type of profile chosen, in particular involute or sinus type, according to FIG. 19, then the calculation of the gear teeth, according to FIG. 20, then allows the cutting of the two wheels with the profile thus defined;

Figures 17 and 20 illustrate the law of space, with three successive zones of radial extension of the needle, stabilization of the length of the needle where the ratio between the exit angle of one of the two guns and the angle of entry into the mechanism is substantially constant, and shortening of the needle.

FIG. 22 shows the superposition of the three states illustrated by FIGS. 3 to 5, and the arrows highlight a phase of contraction CO of the needle 1 between the positions at twelve o'clock and at four hours from its apex 6, a phase ST stability with constant elongation between the four o'clock and eight o'clock positions, and a relaxation phase DE between the eight o'clock and twelve o'clock positions. This weighting is made possible by the use of form cogs, and in particular of the multi-stage cog mechanisms, which make it possible to impose sufficient angular deflections on the barrels, to allow significant changes in shape, and in particular for ability to cross flexible segments as in heart shape. These cogs in shape allow you to safely slow down one cannon in relation to the other.

The wheel of FIG. 27 is an example of optimization of the case of this FIG. 22; to correct the trajectories on angles of 140 ° -80 ° -140 ° as illustrated, instead of 120 ° -120 ° -120 ° which would be more balanced, it is necessary, without weighting by particular stage, i.e. -to say if the upper stage and the lower stage each carry out half of the angular transformation, to design wheels with very strong deformations, and very inclined teeth, difficult to machine, and fragile. Another weighting, for example 20% of the deformation on the lower floor and 80% on the upper floor, makes it possible to have wheels closer to a round shape, easier to machine, and with teeth close to the standard. , therefore with better kinematic and tribological parameters, and less wear.

FIG. 23 shows the evolution of the torque between the flexible segments of the elastic needle, as a function of the angle covered, with a first zone for reducing the length of the elastic needle with consumption of torque, a second holding phase of the length of the needle at substantially constant torque, and a third phase of lengthening the needle with restitution of the torque, FIG. 24 illustrates the evolution of the torque on a barrel, as a function of the angle of rotation of a barrel, and FIG. 25 shows the radial extension of the needle, as a function of the angle of rotation of a barrel.

The elastic needle 1 can be produced in different ways.

In a variant, in the free state, the elastic needle 1 extends on a single plane level comprising the first barrel 2 and the second barrel 4, and the elastic needle 1 is then arranged to be mounted twisted in a position of service under stress in which the first gun 2 and the second gun 4 are superimposed on each other.

In a variant, in the free state, the elastic needle 1 extends over a first plane level comprising the first barrel 2 and over a second plane level comprising the second barrel 4, and comprises a connection zone between the first level plane and the second level plane at a vertex 6 between a first flexible segment 5A carrying the first barrel 2 and a second flexible segment 5B joined to the first flexible segment 5A and carrying the second barrel 4, and the elastic needle 1 is arranged to be mounted without twisting in a service position under stress in which the first barrel 2 and the second barrel 4 are superposed on each other. In another particular variant, when the elastic needle 1 comprises more than two flexible segments 5, in the free state, the elastic needle 1 extends over at most as many parallel levels as flexible segments 5, and is designed to be mounted without twisting in a service position under stress in which the first barrel 2 and the second barrel 4 are superimposed on each other.

In a particular variant intended to facilitate assembly, visible in FIG. 10, in the free state, the elastic needle 1 comprises a breakable element 24 joining the first barrel 2 and the second barrel 4, to facilitate the mounting of the elastic needle 1 on a mobile for driving the first barrel 2 or the second barrel 4, this breakable element 24 being arranged to be broken and authorize the passage of the elastic needle 1 into a service position under stress in which the first gun 2 and the second gun 4 are superimposed on each other.

FIG. 7 illustrates a particular variant in which the elastic needle 1 comprises at least one eye 60, which is arranged to constitute a window for reading an indication appearing on a dial 61 which comprises the mechanism 10, and in front of which extends the elastic hand 1, or that includes a clockwork movement 20, on which the mechanism 10 is arranged to be attached. For example this eye allows to view a city in a GMT application, or to distinguish the morning time from 0 to 12 from the afternoon time from 13 to 24, in a particular application where the training of the display mechanism is made on two revolutions, the first with a certain extension of the elastic hand 1 for the display of the hours of the morning, and the second with a different extension for the display of the hours of the afternoon; of course this variant can also accommodate a display by the top 6 of the needle 1, the presence of such an eye 60 provides reading comfort to the user. FIG. 7 also illustrates two indexes, inside and outside, on either side of this eye 60, which also allow specific readings, depending on the configuration of the dial adopted. One of the great advantages of the invention is to allow great freedom of design of the dial, and the postponement of certain display areas outside of unavailable areas, for example due to the presence of a vortex, or else another complication.

Advantageously, the needle 1 is made of micro-machinable material according to a "LIGA" process, in particular of nickel-phosphorus NiPi2 or the like. Such a needle can be golden, or receive another coloring, the adhesion being satisfactory on such a material. Needle 1 can be colored by different processes: PVD, CVD, ALD, galvano, paint, lacquer, or other coating or ionization.

The needle 1 may comprise a gem setting or the like, and / or a decoration by guilloche, engraving, chamfering, or even enameling, the latter being reserved for zones with low deformation such as the turn of the barrels, a turn of the eye, the tip, or the like.

More particularly, the mechanism 10 constitutes an additional module, which is arranged to be attached to a clockwork movement 20, and the first drive means 11 and the second means 12 for stressing have a common input 71, which is arranged to be driven by a single outlet 21 which comprises the movement 20, such as the roadway which turns in one hour, or the mobile minutes.

In a variant, in addition to or in place of the gear trains, the mechanism 10 comprises, between on the one hand the input mobile 71 arranged to be driven by the movement 20, and on the other hand the first barrel 2 and / or the second barrel 4, at at least one stage, a cam 902, 904. This cam is arranged to drive a differential 912, 914, a first input of which is constituted in particular by the input mobile 71 or by a mobile, a second input of which is a mobile, in particular a rake controlled by this cam 902, 904, and the output meshes with the gear train for transmitting the movement to the first gun 2 or respectively to the second gun 4.

In a first application of this variant, the mechanism 10 comprises, between the input mobile 71 and the first barrel 2 at at least one stage, a single cam 902 arranged to drive a first differential 912 of which a first input is constituted by the input mobile 71, a second input of which is a first mobile or a first rake controlled by the cam 902, and the output of which meshes with the gear train for transmitting movement to the first barrel 2, and between the mobile input 71 and the second barrel 4, the same single cam 902 arranged to drive a second differential 914, a first input of which is constituted by the input mobile 71, a second input of which is a second mobile or a second rake controlled by the cam 902, and whose output meshes with the gear train for transmitting the movement to the second gun 4.

In a second application of this variant, the mechanism 10 comprises, between the entry mobile 71 and the first barrel 2 at at least one stage, a first cam 902 arranged to drive a first differential 912 of which a first entry is constituted by the input mobile 71, a second input of which is a first mobile or first rake controlled by the first cam 902, and the output of which meshes with the gear train for transmitting movement to the first barrel 2; and, between the input mobile 71 and the second barrel 4, a second cam 904 driven by the input mobile and arranged to drive a second differential 914, a first input of which is constituted by the input mobile 71, including one second input is a second rake controlled by the second cam 904, and the output of which meshes with the gear train for transmitting the movement to the second gun 4.

The use of a cam allows highly non-circular trajectories, and also with jumps of the needle. The use of a single cam for the two differentials allows a simultaneous jump of the two guns, for example at midnight; the first differential adds the information from the cam for the first barrel, and the second differential subtracts the information for the second barrel. In another particular variant, at least one wheel that includes the gear mechanism arranged between on the one hand the input mobile 71 arranged to be driven by a movement 20, and on the other hand the first barrel 2 and / or the second barrel 4, at at least one stage, has an incomplete toothing, each missing tooth authorizing a relaxation of the elastic needle 1, by rotation of only one of the barrels 2, 4, during the passage of space corresponding to a missing tooth, or to the missing teeth, so as to command a retraction of the apex 6 of the elastic needle 1.

In particular, it is then possible to use a train comprising one or more, or even all, of the circular wheels, of which at least one circular wheel is devoid of one or more teeth to allow the needle to relax, and to perform a jump. at the end of the path known as the display spiral made by the apex 6 of the needle 1. If for example the first barrel rotates faster than the second barrel, and if the driving road 72 is locally devoid of teeth, the needle tends to contract, for example over two turns, and when the missing teeth release the first barrel, the needle tends but the second barrel does not move, the top of the needle retreats. The advantage of such a variant is that it allows conventional machining of the wheels.

FIG. 24 shows the very low level of torque consumption for the deformation of such a needle 1 in LIGA, during its shortening, which has only a very slight influence on the progress of the movement. Due to the proximity of the exhaust it is nevertheless advantageous to reduce this disturbance as much as possible, which can be obtained with very thin flexible segments 5, typically less than 100 micrometers in width and 200 micrometers in height for a LIGA construction. We understand in Figure 24, where we see that the torque curve as a function of the angle is U-shaped with a very flat cup, that it is advantageous, during design, to choose an angular range of deformation corresponding to the lowest level of the torque curve, so as to minimize the parasitic torque induced, and therefore to minimize the disturbance of the running of the watch. A tiered design with particular weighting helps to choose the optimal angular domains. The correct choice of this angular range also makes it possible to thicken the segments 5 of the needle 1 to make it more visible, without notably increasing its disturbing torque. For comparison, the disturbance induced on the march is less than that caused by a change of date at midnight for a date mechanism.

The invention is illustrated in the figures with a simple shape, but it can be declined with very different needle shapes. For example an asymmetric needle, composed of two ves nested one in the other and of the same directions, each arm of each vee being integral with one of the cannons, and the extreme end of the other arm being linked to the 'similar end of the other vé. Or a needle with double arms, with two segments joining a first vertex and fixed to the two barrels, and two other segments joining a second vertex distant from the first, and fixed to the same barrels. Or a needle with thickened zones on a central zone of the flexible segments, for better visualization of the needle.

The invention also relates to a clockwork movement 20 comprising at least one such display mechanism 10.

The invention also relates to a timepiece 30 comprising at least one timepiece movement 20, and / or comprising at least one such display mechanism 10. More particularly, 21 this timepiece 30 is a watch.

The invention also relates to a scientific apparatus comprising at least one clockwork movement 20, and / or comprising at least one such display mechanism 10.

Claims

REVE N DI CATI O NS

1. Clockwork display mechanism (10) with variable geometry, comprising at least one elastic needle (1) which comprises a first drive barrel (2) integral with a first end of a flexible blade (3) , and a second drive barrel (4) integral with another end of said flexible blade (3), and which comprises a display apex or index which, in an unconstrained free state of said elastic needle (1) wherein both said first barrel (2) and said second barrel (4) are not stressed and are spaced from each other, is spaced from said first barrel (2) and said second barrel (4) , the service position of said elastic needle (1) being a constrained position where said first barrel (2) and said second barrel (4) are coaxial with one another around an outlet axis (D), said display mechanism (10) comprising first drive means (11 ) of said first barrel (2) around said outlet axis (D), and second drive means (13) of said second barrel (4) around said outlet axis (D), said first drive means (1 1 ) and second drive means (13) being arranged to deform said flexible blade (3), by varying the angular position of said second barrel (4) relative to the angular position of said first barrel (2) around said outlet axis (D), and to vary the radial position of said apex or display index relative to said output axis (D), characterized in that said first drive means (1 1) and / or said second means drive (13) comprise an accelerator or retarder device which is arranged to accelerate or stabilize in speed or slow down at least said first barrel (2) and / or said second barrel (4) over at least part of its angular travel, characterized in what said device acc lerator or retarder comprises a first form train (11 1) and / or respectively a second form train (131), and in that said first form train (11 1) and said second form train (131) are arranged to pilot symmetrically said first barrel (2) and said second barrel (4) so that said flexible blade (3) is symmetrical with respect to a radial coming from said outlet axis (D) and passing through said apex or index, over at least part of the angular travel of said elastic needle (1).

2. Mechanism (10) according to claim 1, characterized in that said elastic needle (1) comprises a plurality of flexible segments (5; 5A; 5B) contiguous end to end at at least one vertex, including a first flexible segment (5A) extends between said first barrel (2) and a first apex (6) constituting a said index, and on the other hand said second barrel (4), said display mechanism (10) comprising an input mobile (71 ) arranged to be pivotally driven about an entry axis by a movement (20) and defining an entry angle with a reference, and comprising said first drive means (1 1) of said first barrel (2) , and second means (12) for stressing at least said first flexible segment (5) which are arranged to vary the position of at least said first vertex (6) relative to said outlet axis (D) , said first vertex (6) being at a variable distance from said first barrel (2) as a function of the forces applied to said flexible blade (3) by said second means (12) for stressing, where said second means (12) for stressing includes said second drive means (13) of said second barrel (4) da in a mounted and constrained state of said elastic needle (1) in which both said first barrel (2) is driven by said first drive means (11), and said second barrel (4) is driven by said second means drive (13), characterized in that said first form train (11 1) and said second form train (131) are arranged to pilot symmetrically said first barrel (2) and said second barrel (4) so as to that said first flexible segment (5A) and said second flexible segment (5B) are symmetrical with respect to a radial coming from said outlet axis (D) and passing through said apex (6) joining between said first flexible segment (5A) and said second flexible segment (5B), over at least part of the angular travel of said elastic needle (1).

3. Mechanism (10) according to claim 1 or 2, characterized in that said needle (1) is arranged to perform a total non-retrograde stroke, and that, on said total stroke, the average speed of said first barrel (2) is equal to the average speed of said second gun (4).

4. Mechanism (10) according to one of claims 1 to 3, characterized in that said accelerator or retarder device comprises a device with a first differential (912) on the drive train of said first barrel (2) and / or a second differential (914) on the drive train of said second barrel, and at least one cam (902, 904) constituting an input of a said differential (912, 914).

5. Mechanism (10) according to one of claims 1 to 4, characterized in that said first drive means (11) and / or said second drive means (13) comprise at least one first gear train ( 115; 135) and a second gear train stage (116; 136) each arranged to control part of the shape transformation of said elastic needle (1) over part of its angular travel, with weighting per stage.

6. Mechanism (10) according to one of claims 1 to 5, characterized in that said first drive means (11) and said second drive means (13) respectively comprise at least one first gear train (1 11) and / or at least one second gear train (131), each arranged to accelerate or stabilize in speed or slow down said first barrel (2), and respectively said second barrel (4), over at least part of the stroke angular of said first barrel (2), and respectively of said second barrel (4).

7. Mechanism (10) according to claim 2 and one of claims 1 to 6, characterized in that said first drive means (1 1) and said second means (12) for stressing are arranged to drive said elastic needle (1) over its entire angular travel around said output axis (D), and give it, in projection on a display plane P or on a dial, and at different angular positions of said elastic needle ( 1), at least a first form where said flexible segments (5; 5A; 5B) that comprises said flexible blade (3) do not cross outside of said first barrel (2), and at least a second form where said flexible segments (5; 5A; 5B) which comprises said flexible blade (3) intersect outside said first barrel (2).

8. Mechanism (10) according to claim 7, characterized in that said first form is a form of almond, and said second form is a form of heart.

9. Mechanism (10) according to claim 2 and one of claims 1 to 8, characterized in that said first flexible segment (5A) carries said first barrel (2) at a first end (52), a second flexible segment ( 5B) joined to said first flexible segment (5A) carries said second barrel (4) at a second end (54), and in that, in said free state of said elastic needle (1), said first end (52) and said second end (54) are distant from each other or form a non-zero angle with each other from said vertex (6) joining said first flexible segment (5A) and said second flexible segment (5B) .

10. Mechanism (10) according to one of claims 1 to 9, characterized in that the outlet of said second drive means (13) of said second barrel (4) is coaxial with the output of said first drive means (1 1) of said first barrel (2).

11. Mechanism (10) according to one of claims 1 to 10, characterized in that said first form train (11 1) and said second form train (131) are arranged to accelerate or respectively brake said first gun (2 ), and to brake or respectively accelerate said second barrel (4), over only part of the angular travel of said elastic needle (1).

12. Mechanism (10) according to one of claims 1 to 1 1, characterized in that said first form train (11 1) and / or said second form train (131) comprises at least one pair of wheels arranged for cooperate in meshing with one another and whose primitive curves of the teeth are not of revolution.

13. Mechanism (10) according to claim 5 and one of claims 1 to 12, characterized in that said first gear train (1 15; 135) and said second gear train (116; 136) respectively comprise a said first gear train (11 1) and a said second gear train (131).

14. Mechanism (10) according to claim 2 and one of claims 1 to 13, characterized in that, in the free state, said elastic needle (1) extends over a first plane level comprising said first barrel ( 2) and on a second plane level comprising said second barrel (4), and comprises a connection zone between said first plane level and said second plane level at a said vertex (6) between a first flexible segment (5A) carrier of said first barrel (2) and a second flexible segment (5B) contiguous to said first flexible segment (5A) and carrier of said second barrel (4), and in that said elastic needle (1) is arranged to be mounted without twisting in a constrained service position in which said first barrel (2) and said second barrel (4) are superimposed on each other.

15. Mechanism (10) according to claim 2 and one of claims 1 to 14, characterized in that, in the free state, said elastic needle (1) extends over as many parallel levels as said flexible segments (5), is arranged to be mounted without twisting in a service position under stress in which said first barrel (2) and said second barrel (4) are superimposed on each other.

16. Mechanism (10) according to one of claims 1 to 14, characterized in that, in the free state, said elastic needle (1) extends over a single plane level comprising said first barrel (2) and said second barrel (4), and in that said elastic needle (1) is arranged to be twisted in a service position under stress in which said first barrel (2) and said second barrel (4) are superimposed on each other.

17. Mechanism (10) according to one of claims 1 to 16, characterized in that, in the free state, said elastic needle (1) comprises a breakable element (24) joining said first barrel (2) and said second barrel (4), to facilitate the mounting of said elastic needle (1) on a mobile for driving said first barrel (2) or said second barrel (4), said breakable element (24) being arranged to be broken and allow the passage of said elastic needle (1) in a service position under stress in which said first barrel (2) and said second barrel (4) are superimposed on each other.

18. Mechanism (10) according to one of claims 1 to 17, characterized in that said elastic needle (1) comprises at least one eye (60) arranged to constitute a window for reading an indication appearing on a dial ( 61) that comprises said mechanism (10) and in front of which extends said elastic needle (1), or that comprises a clockwork movement (20) on which said mechanism (10) is arranged to be attached.

19. Mechanism (10) according to one of claims 1 to 18, characterized in that said mechanism (10) constitutes an additional module arranged to be attached to a clockwork movement (20), and in that said first means drive (11) and said second means (12) for stressing have a common input (71) arranged to be driven by a single output (21) that includes said movement (20).

20. Mechanism (10) according to claims 4 and 5, and according to one of claims 1 to 19, characterized in that said mechanism (10) comprises, on the one hand an input mobile (71) arranged for be driven by a movement (20), and secondly said first barrel (2) and / or said second barrel (4), at at least one said stage, a cam (902, 904) arranged to pilot a differential (912, 914), a first input of which is constituted by said input mobile (71), a second input of which is a mobile or a rake controlled by said cam (902, 904), and the output of which meshes with the cog transmission transmission to said first gun (2) or second gun respectively (4).

21. Mechanism (10) according to claim 20, characterized in that said mechanism (10) comprises, between said input mobile (71) and said first barrel (2) at at least one said stage, a single cam (902) arranged to drive a first differential (912), a first input of which is constituted by said input mobile (71), a second input of which is a first controlled rake by said cam (902), and the output of which meshes with the gear train for transmitting movement to said first barrel (2), and between said input mobile (71) and said second barrel (4), the same so-called cam (902) ) single arranged to drive a second differential (914), a first input of which is constituted by said input mobile (71), a second input of which is a second rake controlled by said cam (902), and whose output meshes with the gear train for transmitting movement to said second gun (4).

22. Mechanism (10) according to claim 21, characterized in that said mechanism (10) comprises, between said input mobile (71) and said first barrel (2) at at least one said stage, a first cam (902) arranged to drive a first differential (912), a first input of which is constituted by said input mobile (71), a second input of which is a first rake controlled by said first cam (902), and the output of which meshes with the gear train for transmitting movement to said first barrel (2), and between said input mobile (71) and said second cannon (4), a second cam (904) driven by the input mobile and arranged to pilot a second differential (914), a first input of which is constituted by said input mobile (71), a second input of which is a second rake controlled by said second cam (904), and the output of which meshes with the gear train of the audit second movement canon me (4).

23. Mechanism (10) according to claim 5 and according to one of claims 1 to 22, characterized in that at least one wheel that comprises the gear mechanism arranged between on the one hand an input mobile (71) arranged to be driven by a movement (20), and on the other hand said first barrel (2) and / or said second barrel (4), at at least one said stage, has an incomplete toothing, each missing tooth authorizing a relaxation of said elastic needle (1), by rotation of only one of said barrels (2; 4) during the passage of the space corresponding to a missing tooth, so as to command a retraction of the top (6) of said elastic needle (1).

24. Clock movement (20) comprising at least one display mechanism (10) according to one of claims 1 to 23.

25. Timepiece (30) comprising at least one timepiece movement (20) according to claim 24.

26. Timepiece (30) according to claim 25, characterized in that said timepiece (30) is a watch.

27. Scientific apparatus comprising at least one clockwork movement (20) according to claim 24.