CH715220A2 - Clock display mechanism with elastic hand. - Google Patents

Abstract

The invention relates to a clockwork display mechanism (10) with an elastic hand (1) comprising first (11) and second (13) drive means (11), around an output axis (D ), a first (2) and a second (4) barrel mounted at the ends of a flexible blade (3), and comprising a display index remote from the barrels (2, 4). These drive means are arranged to deform the flexible blade (3), by varying the angular position of one barrel relative to the other around the outlet axis (D), and to vary the radial position of the display index relative to this axis, this mechanism (10) comprises a first differential on the gear train of the first barrel (2), an input of which is constituted by a first cam (92), and a second differential on the drive train of the second barrel (4), an input of which is formed by a second cam. The first differential and the second differential carry satellites (82, 84) each comprising an eccentric probe arranged to follow its respective cam (92, 94). The invention makes it possible to produce a trajectory of the display index or of a vertex (6) of the flexible blade (3) which is not round, for example square or linear. With the invention, it is also possible to obtain a day / night, AM / PM, or different time zone display by modifying the shape and length of the elastic hand (1).

Description

Description Field of the Invention The invention relates to a clockwork display mechanism with variable geometry, comprising at least one elastic needle which comprises a first drive barrel secured to a first end of a flexible blade , and a second drive barrel integral with another end of said flexible blade, and comprising a display 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 constraint 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 l to each other around an output axis, said display mechanism comprising first means for driving said first barrel to turn of said outlet axis, and of the second drive means of said second barrel around said outlet axis, said first drive means and second drive means being arranged to deform said flexible blade, by varying the angular position of said second gun relative to the angular position of said first gun around said output axis, and to vary the radial position of said display index relative to said output axis.

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

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

The invention relates to the field of clockwork display mechanisms, and more particularly for timepieces with complications, the invention can be used both for static timepieces such as pendulums or clocks, as for watches, due to the small dimensions of the mechanism according to the invention.

BACKGROUND OF THE INVENTION Good viewing of the display elements on a timepiece is important for the user.

The dials of many timepieces are not circular, and it is advantageous to have solutions which make it possible to occupy all the available surface, for even better visualization.

The design of a variable geometry display mechanism makes it possible to break a certain monotony of the displays, and to make the display more lively, with different aspects depending on the time of day, or according to particular time periods. For example, among a very large number of other possible applications, an AM / PM display can be simply provided by the shape of a needle, which has a first aspect during the twelve hours of the morning, and a second aspect during the rest of the day; we can also distinguish day / night displays, time zone displays, or others.

Claims (18)

Summary of the invention [0008] Elastic needles, and display mechanisms comprising such elastic needles, have been described in documents EP 2 863 274, EP 3 159 751, and EP 18 186 552, which disclose numerous variants. The invention proposes to further simplify such a mechanism and make it even more compact and economical to produce. To this end, the invention relates to a clockwork display mechanism with variable geometry, according to claim 1. The invention relates to a timepiece movement comprising at least one such display mechanism. The invention relates to a watch comprising at least one such movement, and / or at least one such display mechanism. Brief description of the drawings [0013] Other characteristics and advantages of the invention will appear on reading the detailed description which follows, with reference to the accompanying drawings, where: fig. 1 shows, schematically, partially, and in 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; fig. 2 shows, schematically, in exploded view and in perspective, the mechanism of FIG. 1; CH 715 220 A2 fig. 3 shows, schematically and in plan, the mobile planet carrier chassis that includes this mechanism; fig. 4 is a functional diagram of a differential such as this mechanism includes; fig. 5 represents, schematically and in plan, an oval dial in front of which moves an elastic hand which includes such a display mechanism, which hand is represented in two different positions: in solid line at twelve o'clock, and in broken line at two hours; fig. 6 shows, schematically, partially, and in perspective, a display mechanism according to the invention, with the elastic needle on its barrels; fig. 7 is a block diagram of a timepiece comprising a movement and such a display mechanism; fig. 8 shows, schematically, partially, and in perspective, a differential mechanism according to the teachings of application EP 18 186 552; fig. 9 is a functional diagram of a differential of the mechanism of fig. 8; fig. 10 represents, similarly to FIG. 2, such a display mechanism, the cams of which are kept fixed, and FIG. 11 illustrates, similarly to FIG. 5, the associated ovoid trajectory of a vertex of the elastic needle; fig. 12 represents, similarly to FIG. 2, such a display mechanism, the input planet carrier chassis of which is kept fixed, preventing the rotation of the elastic needle about its exit axis and allowing only its elongation or contraction, and FIG. 13 illustrates, similarly to FIG. 5, the associated trajectory of a vertex of the elastic needle, which successively takes the form of almonds and hearts; fig. 14 represents, similarly to FIG. 2, such a display mechanism, the cams of which are, on demand, either kept fixed, or set in motion, in particular in a limited manner; and fig. 15 illustrates, similarly to FIG. 5, the associated trajectory of a vertex of the elastic needle, in a square with rounded corners when the cams are stopped, and in a radial when the cams are in rotation; fig. 16 illustrates, similarly to FIGS. 10, 12, and 14, another variant where one of the cams is carried by the planet carrier chassis. Detailed description of the preferred embodiments Application EP 18 186 552, incorporated herein by reference, relating to a clockwork display mechanism with variable geometry with elastic hand, describes a first actuation mechanism by means of mobile with shaped teeth. Such an embodiment allows the execution of very innovative displays in watchmaking, and is however expensive, and reserved for luxury items. The same application also describes a second case of actuation mechanism by means of a first differential on the train of the first barrel and a second differential on the train of the second barrel, and at least one cam constituting an entry d 'such a differential. Therefore, it is necessary to find and size an adequate planetary (differential) gear. Planetary gears have the advantage of achieving high transmission ratios in a small footprint. The input and output trees are an extension of each other. There are many possibilities for combining gears. They allow, in particular, to make interesting gearboxes. In this case, it is a question of controlling one of the inputs of the differential, so as to generate an advance and respectively a delay of an equivalent specific value on each of the ends of the needle. And, when this value is zero, a transmission ratio of 1 must be obtained (the positive value means that the direction must also be identical). [0016] FIG. 8 shows an example of such an embodiment, with a heart-shaped cam in the right part of the figure, traversed by a curved sickle-shaped lever comprising an internally toothed part, with which a wheel of a first differential cooperates, in part left of the figure, a second differential being visible in the rear right part of the figure, these two differentials attacking two coaxial guns. The lever of this figure does not have a return spring, because it is the elastic needle which advantageously fulfills this function. The lever actuates the crown, which by means of the satellites visible on the principle diagram of one of the two differentials, makes it possible to generate the necessary advance or delay. This mechanism of FIG. 8 performs well the function of generation of advance or delay on the guns, but remains bulky and contains many components. CH 715 220 A2 The invention aims to further simplify the mechanism and make it even more compact and economical to produce. In particular, when it comes to implanting the elastic hand on a small caliber, like a ladies' watch, and moreover on the minute hand. The main difficulty is linked to the low torque available. It is therefore necessary to create a mechanism with the lowest possible energy consumption. By diverting the normal operation of a differential, the invention proposes to control the satellite. By installing a probe in the satellite, and by controlling the latter with a round cam, we obtain a speed ratio equal to one between the sun wheel and the chassis carrying the satellites: the assembly then behaves like a mobile. The replacement of the round cam in this example by a cam of adequate shape now allows to control the advance or delay that we want to get on the barrel. It should be noted that here again, the mechanism does not have a return spring to maintain contact with the feeler on the cam, because it is the elastic needle which makes it possible to fulfill this function. In the case of a single chassis carrying the two satellites of the first and second differential, one above the chassis for the second gun, and the other below the chassis for the first gun, we obtain a system capable of reproducing the same advance and delay as the mechanism of the request EP 18 186 552 or of the present fig. 8, with only four teeth. The cams shown in FIG. 2 thus make it possible to obtain the trajectory of the point of the needle of FIG. 5. The invention thus relates more particularly to a clockwork display mechanism 10 of variable geometry, comprising at least one elastic needle 1. Such an elastic needle, and display mechanisms comprising such elastic needles, have been described in documents EP 2 863 274, EP 3 159 751, and EP 18 186 552, which disclose numerous variants. This elastic needle which 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 the flexible blade 3. This flexible blade 3 can be a continuous blade, or a blade comprising a succession of segments 5 joined two by two at the level of vertices 6, as visible in FIGS. 5 and 6. This flexible blade 3 has a display index which, in an unconstrained free state of the elastic needle 1 in which both the first barrel 2 and the second barrel 4 are not subjected to any stress and are distant one from the other, is distant from the first barrel 2 and the second barrel 4, the service position of the elastic needle 1 being a constrained position where the first barrel 2 and the second barrel 4 are coaxial with one another other around an output axis D. In particular in a variant comprising butted segments 5, the display index is advantageously, but not necessarily, constituted by a vertex 6. The display mechanism 10 includes first drive means 11 of the first barrel 2 around the outlet axis D, and second drive means 13 of the second barrel 4 around the outlet axis D . Variants where the first barrel 2 and the second barrel 4 are not coaxial are not described here, they remain achievable for certain special displays, in particular displays which are not of revolution, such as retrograde displays or the like. The first drive means 11 and the 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 output axis D, and to vary the radial position of the display index relative to the output axis D. According to the invention, the display mechanism 10 includes a first differential 912 on the drive train of the first barrel 2, and an input of which is constituted by a first cam 92 or 820, and a second differential 914 on the drive train of the second barrel 4, and an input of which is constituted by a second cam 94 or 810. Depending on the configuration adopted, the first cam can be a fixed cam or a movable cam, and the second cam can be, from the same way, a fixed cam or a movable cam. Figs. 10, 12, 14, 16, illustrate certain particular configurations. Advantageously, the first differential 912 and the second differential 914 comprise a common chassis satellite carrier or two synchronous chassis each satellite carrier, carrier or carrier respectively of the satellites 82, 84, which each comprise an eccentric probe 83, 85, which is arranged to follow its respective cam 92, 820, 94, 810, depending on the variant. More particularly, the first drive means 11 or the second drive means 13 are arranged to drive another input of an input differential, which is another input than the cam mentioned above constituting a inputs of the differential concerned, This input differential is one of the first differential 912 and second differential 914; for example on the variant of FIGS. 1 and 2, the input differential is the second differential 914. This other input is constituted by a first satellite of the input differential. The first satellite is mounted for free rotation on an input planet carrier frame 80 which is itself mounted for free rotation around the output axis CH 715 220 A2 D. And the sun gear of the input differential is constituted either by a first toothing 21 which carries the first barrel 2 when the input differential is the first differential 912, or by a second toothing 41 which carries the second canon 4 when the input differential is the second differential 914. By “satellite carrier chassis” is meant a chassis capable of carrying at least one satellite, on any of its faces. More particularly, the other of the first differential 912 and second differential 914 is an output differential, of which another input is constituted by a second satellite of the output differential. This second satellite is mounted to rotate freely on the input planet carrier frame 80 as in FIG. 2, or else on an output satellite carrier chassis which is mounted to rotate freely around the output axis D and synchronous with the input satellite carrier chassis 80. The output pinion of the output differential consists of a second toothing 41 carried by the second barrel 4 when the input differential is the first differential 912, or by a first toothing 21 carried by the first barrel 2 when the input differential is the second differential 914. More particularly, the second satellite is mounted to rotate freely on the input planet carrier chassis 80, on the face opposite to that which carries the first satellite, as visible in FIGS. 2 and 3, which show the input planet carrier frame 80 having counterbores on the upper and lower faces, and upper pivot pins 81 and lower 89. More particularly, the first differential 912 comprises a first satellite 82 comprising a first eccentric finger 83, which is arranged to travel a first internal track 93 of the first cam 92 or 820, in particular a fixed cam, and is returned against the first internal track 93 by the elasticity of the elastic needle 1. In the same way, the second differential 914 comprises a second satellite 84 comprising a second eccentric finger 85, which is arranged to traverse a second internal track 95 of the second cam 94 or 810, in particular a fixed cam, which is biased against the second internal track 95 by the elasticity of the elastic needle 1. It is advantageous to use the elasticity of the elastic needle 1 itself to save a return component which would be necessary to ensure the plating of each probe on its cam track. It is understood that the relative arrangement of the cams 92, 820, 94, 810, can be carried out in different ways: - or at least one of the cams is distinct from the common planet carrier chassis or from the two synchronous planet carrier chassis; - or else the two cams are distinct from each other and each distinct from the common planet carrier chassis or from the two synchronous planet carrier chassis; - or even at least one of the cams is carried by the common planet carrier chassis or one of the two synchronous planet carrier chassis. In a particular embodiment, to form an additional block for easy mounting, the first cam, 92 or 820, in particular a fixed cam, is fixed in indexed manner to the second cam, 94 or 810, in particular a fixed cam, with which it forms a box. This box contains the first barrel 2, the second barrel 4, and, interposed freely in rotation between the first cam 92 or 820, in particular a fixed cam, and the second cam 94 or 810, in particular a fixed cam, or else a door frame -single input satellite 80 carrying all the mobiles of the first differential 912 and the second differential 914, or an input satellite carrier 80 carrying all the mobiles of the first differential 912 and a satellite carrier chassis output mounted freely rotating around the output axis D and synchronous with the input planet carrier frame 80 and carrying all the mobiles of the second differential 914. More particularly still, the first satellite projects radially, with reference to the output axis D and with respect to the first cam, 92 or 820, in particular a fixed cam, and to the second cam, 94 or 810, in particular a fixed cam, and is arranged to cooperate with an internally toothed ring, which comprises the display mechanism 10, for driving this at least one elastic needle 1. The implementation of the invention makes it possible to obtain a wide variety of different displays, depending on the kinematics imposed on the cams and on the planet carrier chassis, or on the planet carrier chassis when there are several. Indeed, it is possible to impose a shutdown of a part of these constituents, which can be a permanent stop with a permanent fixing on a plate, a bridge, or the like, or else which can be a controlled stop of the mobile concerned which can be released by the user or by the movement to be rotated, for a limited time or not, for the temporary obtaining of a particular display effect. Thus, in a variant illustrated in FIG. 10, the first cam 92 or 820 and the second cam 94 or 810 are fixed relative to a plate or a bridge that comprises the display mechanism, and the common planet carrier frame 80 in the case of the figure, or the two synchronous planet carrier chassis, in another variant not illustrated, is or are driven by a control mechanism of the display mechanism 10. FIG. 11 shows the ovoid trajectory T of a vertex 6 of the needle 1, associated with this mechanism. In another variant, the first cam, 92 or 820, and the second cam, 94 or 810, are pivoting and synchronous. Thus, in a variant illustrated in FIG. 12, the first cam, 92 or 820, and the second cam, 94 or 810, are pivoting and synchronous, and the common planet carrier frame 80 illustrated, or the two synchronous frames, each planet carrier, is or are fixed by relative to a plate or a bridge that comprises the display mechanism 10. FIG. 13 shows the linear trajectory of a vertex 6 of the needle 1, associated with this mechanism, since this elastic needle CH 715 220 A2 1 here does not rotate around the output axis D, but changes length according to the shape of the cams, between a minimum radius RMIN and a maximum radius RMAX; an application consists, for example, of a linear power reserve display. In another variant still illustrated by FIG. 14, the first cam, 92 or 820, and the second cam, 94 or 810, are pivotable, and can be locked in a fixed position, but not permanently, because they can perform a rotational movement on demand, in particular but not limited to one turn or an entire number of turns. Here the first cam, 92 or 820, and the second cam, 94 or 810, are pivoting and synchronous, and the common planet carrier chassis 80 illustrated, or the two synchronous chassis, each planet carrier, in another variant not illustrated , is or are pivotally coaxial with respect to the first cam, 92 or 820, and the second cam, 94 or 810. More particularly, the display mechanism 10 then includes a demand control mechanism for pivoting together the first cam, 92 or 820, and the second cam, 94 or 810, and to vary the radial extension of the elastic needle 1 relative to the outlet axis D. [0047] FIG. 15 shows the square trajectory T of a vertex 6 of the needle 1, associated with the mechanism of FIG. 14. This vertex 6 is distant from the exit axis D by a distance which varies between a minimum radius RMIN and a maximum radius RMAX. During operation, when the cams, 92 or 820, and 94 or 810, are stopped, this top 7 follows the square trajectory with rounded corners T. When the rotation of the cams is controlled, the needle 1 points always the same direction, but changes in length, like a heartbeat: here needle 1 has the shape of a heart that pulsates on demand. [0048] FIG. 16 illustrates, in a similar manner to FIGS. 10, 12, and 14, another variant where one of the cams, here the second cam 810, is carried by the planet carrier frame 80: it cooperates with the second eccentric finger 85 of the second satellite 84 which is carried by the pivot pin 81 of the same planet carrier frame 80; on the underside of this planet carrier frame 80 is similarly guided the first satellite 82, the first eccentric finger 83 of which cooperates with the first internal track 93 of the first cam 92. Of course, the symmetrical configuration can be achieved with a first cam 820 formed at the level of the planet carrier frame 80, and a second cam 94 external to the latter. The invention also relates to a timepiece movement 900 comprising at least one such display mechanism 10. The invention also relates to a watch 1000 comprising at least one such movement 900, and / or at least one such display mechanism 10. In summary, the invention makes it possible to generate advance and / or delay on the two barrels of the elastic needle, making it possible to generate complex trajectories, all in a very simple, compact and inexpensive manner. greedy couple and therefore very reliable. claims 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 comprising a display index which, in an unstressed free state of said elastic needle (1) in which at both said first barrel (2) and said second barrel (4) are not stressed and are distant from each other, is distant from said first barrel (2) and said second barrel (4), the position of service of said elastic needle (1) being a constrained position where said first barrel (2) and said second barrel (4) are coaxial with each other around an outlet axis (D), said mechanism d display (10) comprising first drive means (11) of said first canoe n (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 (11) and second means drive (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 display index relative to said output axis (D), characterized in that said display mechanism comprises a first differential (912) on the drive train of said first barrel (2) and of which an inlet consists of a first cam (92, 820), and a second differential (914) on the drive train of said second barrel (4) and of which an inlet consists of a second cam (94, 810) , and in that said first differential (912) and said two th differential (914) are carriers of satellites (82; 84) each comprising an eccentric probe (83; 85) arranged to follow its respective cam (92; 94). 2. Display mechanism (10) according to claim 1, characterized in that said second cam (94; 820) is synchronous with said first cam (92; 810). 3. Display mechanism (10) according to claim 1 or 2, characterized in that said first differential (912) and said second differential (914) comprise a common planet carrier chassis or two synchronous chassis each carrier planet carrier or respectively carrying said satellites (82; 84) which each comprise an eccentric probe (83; 85) arranged to continue its respective cam (92, 820; 94, 810). 4. Display mechanism (10) according to claim 3, characterized in that at least one of said cams (92, 820; 94, 810) is distinct from said common planet carrier chassis or from the two said synchronous carrier chassis. satellite. CH 715 220 A2 5. Display mechanism (10) according to claim 4, characterized in that the two said cams (92, 820; 94, 810) are distinct from each other and each distinct from said common planet carrier chassis or from said two synchronous chassis planet carrier. 6. Display mechanism (10) according to claim 3, characterized in that at least one of said cams (92, 820; 94, 810) is carried by said common planet carrier chassis or one of the two said synchronous chassis planet carrier. 7. Display mechanism (10) according to one of claims 1 to 5, characterized in that said first cam (92, 820) and said second cam (94, 810) are fixed relative to a plate or a bridge that comprises said display mechanism, and in that said common planet carrier chassis or said two synchronous satellite carrier chassis, is or are driven by a control mechanism of said display mechanism (10). 8. Display mechanism (10) according to one of claims 1 to 5, characterized in that said first cam (92, 820) and said second cam (94, 810) are pivotable and synchronous, and in that said common satellite carrier chassis or said two synchronous satellite carrier chassis, is or are fixed relative to a plate or a bridge that includes said display mechanism. 9. Display mechanism (10) according to one of claims 1 to 5, characterized in that said first cam (92, 820) and said second cam (94, 810) are pivotable and synchronous, and in that said common planet carrier chassis or said two synchronous planet carrier chassis, is or are pivotally coaxial with respect to said first cam (92, 820) and said second cam (94, 810). 10. Display mechanism (10) according to claim 8 or 9, characterized in that said display mechanism (10) comprises a demand control mechanism for pivoting together said first cam (92, 820) and said second cam (94, 810), and for varying the radial extension of said elastic needle (1) relative to said outlet axis (D). 11. Display mechanism (10) according to one of claims 1 to 10, characterized in that said first drive means (11) or said second drive means (13) are arranged to drive another input d '' an input differential, which is one of said first differential (912) and second differential (914), constituted by a first satellite of said input differential, said first satellite being mounted to rotate freely on an input chassis (80) mounted freely in rotation about said output axis (D), and the sun gear of said input differential being constituted by a first toothing (21) which carries said first barrel (2) when said input differential is said first differential (912), or by a second toothing (41) carried by said second barrel (4) when said input differential is said second differential (914). 12. Display mechanism (10) according to claim 11, characterized in that the other of said first differential (912) and second differential (914) is an output differential, of which another input is constituted by a second satellite of said output differential, said second satellite being mounted for free rotation on said input chassis (80) or on an output chassis for free rotation about said output axis (D) and synchronous with said input chassis (80) , and the sun gear of said output differential being constituted by a second toothing (41) which carries said second barrel (4) when said input differential is said first differential (912), or by a first toothing (21) which carries said first barrel (2) when said input differential is said second differential (914). 13. Display mechanism (10) according to claim 12, characterized in that said second satellite is mounted to rotate freely on said input frame (80), on the face opposite to that which carries said first satellite. 14. Display mechanism (10) according to one of claims 1 to 13, characterized in that said first differential (912) comprises a first satellite (82) comprising a first eccentric finger (83) arranged to traverse a first track internal (93) of said first cam (92, 820) and biased against said first internal track (93) by the elasticity of said elastic needle (1), and in that said second differential (914) comprises a second satellite ( 84) comprising a second eccentric finger (85) arranged to traverse a second internal track (95) of said second cam (94, 810) and biased against said second internal track (95) by the elasticity of said elastic needle (1) . 15. Display mechanism (10) according to one of claims 1 to 14, characterized in that said first cam (92, 820) is fixed in indexed manner to said second cam f (94, 810) with which it forms a box containing said first barrel (2), said second barrel (4), and, interposed freely in rotation between said first cam (92, 820) and said second cam (94, 810), or else an input frame ( 80) single carrier of all of the mobiles of said first differential (912) and of said second differential (914), or else an input chassis (80) carrying all of the mobiles of said first differential (912) and an output chassis mounted free in rotation around said output axis (D) and synchronous with said input frame (80) and carrying all the mobiles of said second differential (914). 16. Display mechanism (10) according to claim 11 and one of claims 1 to 15, characterized in that said first satellite is radially projecting, with reference to said output axis (D) and relative to said first cam fixed (92, 820) and to said second fixed cam (94, 810), and is arranged to cooperate with an internally toothed ring, which comprises said display mechanism (10), for driving said at least one needle elastic (1). 17. Clock movement (900) comprising at least one display mechanism (10) according to one of claims 1 to 16. CH 715 220 A2 18. Watch (1000) comprising at least one movement (900) according to claim 17, and / or at least one display mechanism (10) according to one of claims 1 to 18. CH 715 220 A2

CH 715 220 A2

CH 715 220 A2