Anterograde display device for a timepiece

Abstract

One aspect of the invention relates to an antegrade display mechanism (100) comprising: a first wheel (110) adapted to be driven by a clockwork movement; a second wheel (120) coaxial with the first wheel (110) and linked to the first wheel (110) by an elastic element (160); a first intermediate wheel (150) driven directly by the first wheel (110) and which directly drives a third wheel (130) carrying a display element (2); said third wheel (130) comprising a smooth angular sector (131) where at least two teeth are truncated; a fourth wheel (140) coaxial and rotationally fixed to the third wheel (130), said fourth wheel (140) meshing with said second wheel by means of a second intermediate wheel (170);the anterograde display mechanism being configured so that the rotational speed of the second wheel (120) is less than the rotational speed of the first wheel (110) when the display member (2) is driven in its angular displacements by successive short jumps of an angle (a) between two reference points separated by the first angle (a), so as to progressively arm the elastic member (160) during these successive short jumps, and so that when the teeth of the intermediate wheel (150) meet the smooth angular sector (131) of the third wheel (130), the elastic member (160) disarms, causing the instantaneous passage of the smooth angular sector (131) and causing the displacement by a long jump of angle (β) of said display member (2).;

Description

Technical field of the invention

[0001] The field of the invention relates to anterograde, or "anti-retrograde" display mechanisms, i.e. display mechanisms configured to pivot a display member, in the direction of travel, by a first angular distance greater than a second angular distance.

[0002] The invention also relates to a watch movement comprising such an anterograde display mechanism, as well as a timepiece comprising such a watch movement. Technological background

[0003] Anterograde display mechanisms are traditionally used to display information relating to the current time or information relating to the date.

[0004] In a classic timepiece, the marks of the current time or date graduation are generally distributed uniformly around a circumference of the dial. However, in certain situations, it is desirable for the display organ not to remain in a stable position on a particular sector of the dial to avoid the display organ masking, at a certain moment, for example a complication (for example a tourbillon) or another display (for example a moon phase) which would be placed in the particular sector of the dial in question.

[0005] To prevent a display member from remaining indexed in a predefined sector of the dial, it is known to use antegrade display mechanisms allowing the display member to jump forward by a greater angular distance than for the other graduations, over a predefined angular sector, so that the display member does not stop in this angular sector.

[0006] Patent CH 699 736 describes an exemplary embodiment of such an anterograde display mechanism applied to a date, the marks of the date graduation of which are not distributed uniformly over a circumference but are arranged so that the angular distance separating marks 15 and 16 is greater than the angular distance separating the other marks from 1 to 31. Thus, between marks 15 and 16, an angular sector of the dial of the timepiece is created without marks in which the date hand does not stop, but makes a jump of a second angle greater than a first angle separating the other marks of the graduation. The anterograde display mechanism described in this patent is based on the use of several toothed sectors and their complex cooperation.

[0007] Patent document CH 713 209 describes another example of an anterograde display mechanism also applied to a date. In this document, the angular distance separating the markers 31 and 1 is greater than the angular distance separating the other markers between 1 and 31. To switch the date hand from marker 31 to marker 1 without stopping, the document proposes the use of a snail cam secured to the date wheel carrying the date hand, said date wheel being advanced by one step per day by a date actuator. The snail cam cooperates with a lever and a spring to ensure the stable angular position of the cam between markers 1 to 31.The snail cam comprises a toothed portion comprising 30 teeth for the 30 stable positions between the marks 1 and 31, and a smooth portion extending in an angular sector corresponding to the angular sector of the dial without graduation (between the marks 31 and 1) allowing, under the action of the lever, to pivot the cam and the date wheel by an angle corresponding to the angle between the marks 31 to 1. Patent document CH 707 439 A2 shows all the characteristics of the preamble of the appended claim 1.This document does not show a first intermediate wheel driven directly by a first wheel and which directly drives a third wheel, called the display wheel, cooperating with a display member, said third wheel comprising a smooth angular sector where at least two teeth are truncated, a fourth coaxial wheel and integral in rotation with the third wheel, said fourth wheel meshing with said second wheel via a second intermediate wheel, the anterograde display mechanism being configured so that when the teeth of the intermediate wheel meet the smooth angular sector of the third wheel, the elastic member disarms causing the instantaneous passage of the smooth angular sector and causing the angular displacement by a long angle jump of said display member.

[0008] However, either these anterograde mechanisms are complex to implement and integrate into a watch case, or these mechanisms are very sensitive to manufacturing variations, and in particular machining, causing shifts in the jumps with respect to the graduations, which makes these mechanisms difficult to industrialize.

[0009] Therefore, there is a need to improve anterograde display mechanisms, in particular to make them easier to industrialize, and therefore less sensitive to dimensional variations of the parts, space-saving, easy to implement and more reliable. Summary of the invention

[0010] In this context, the invention proposes an anterograde display mechanism for a timepiece comprising a display having a graduation having a plurality of marks distributed over a circumference of the display, the graduation being configured so that the angular distance separating two successive marks corresponds to a second angle β greater than a first angle α separating two of the other successive marks, the anterograde display mechanism being configured to drive a display member in its angular movements by successive short jumps of angle α between two marks separated by the first angle α and by a long jump of angle β between two marks of the graduation separated by the second angle β, the anterograde display mechanism being characterized in that it comprises: a first wheel, called the driving wheel, capable of being driven by a clockwork movement; a second wheel coaxial with the first wheel and linked to the first wheel by an elastic member; a first intermediate wheel driven directly by the first wheel and which directly drives a third wheel, called the display wheel, cooperating with said display member; said third wheel comprising a smooth angular sector where at least two teeth are truncated; a fourth wheel coaxial and integral in rotation with the third wheel, said fourth wheel meshing with said second wheel via a second intermediate wheel; the anterograde display mechanism being configured so that the rotation speed of the second wheel is lower than the rotation speed of the first wheel when the display member is driven in its angular movements by successive short jumps of an angle α between two marks separated by the first angle α, so as to progressively arm the elastic member during these successive short jumps, and so that when the teeth of the intermediate wheel meet the smooth angular sector of the third wheel, the elastic member is disarmed causing the instantaneous passage of the smooth angular sector and causing the angular movement by a long jump of angle β of said display member.

[0011] In addition to the characteristics mentioned in the preceding paragraph, the anterograde display mechanism according to the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations: the first wheel is capable of being driven in jumps by said clockwork movement; the first wheel comprises a number of teeth n 1, the number of teeth n 1 being equal to the number of marks on the display graduation; the second wheel has a number of teeth n 2 greater than the number of teeth n 1 of the first wheel; the third wheel has an effective number n 3 eff of teeth distributed over a toothed portion and a number of truncated teeth n 3 trunk on the smooth angular sector, the set forming a number n 3 horseof equivalence of teeth on the complete circumference of the third wheel, the number n 3 horse of equivalence of teeth on the complete circumference of the third wheel being equal to the number of teeth n 2 of the second wheel; the number of truncated teeth n 3 trunk on the smooth angular sector of the third wheel is an integer corresponding to the ratio of the second angle β to the first angle α; the fourth wheel has a number of teeth n 4 equal to the number of teeth n 2 of the second wheel; the number of teeth n 2 of the second wheel is determined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 , Or : α is the first angle corresponding to a first angular distance separating at least two following marks of the graduation; β i is the second angle, greater than the first angle α, corresponding to a second angular distance, different from the first angular distance, separating at least two other marks of the graduation following each other at the level of a sector If of graduation; i is an integer between 1 and j ; j is an integer corresponding to the total number of sectors If of the graduation where two following graduation marks are spaced by a second angle β i greater than the first angle α; the elastic member is a leaf spring, a strip, a flat spring, or a spiral spring; the elastic member is integral with the first wheel so that it comprises a first end integral with said first wheel and a second end connected to the second wheel, or the elastic member is integral with the second wheel so that it comprises a first end integral with said second wheel and a second end connected to the first wheel; the display comprises a date scale with 31 markers and in that the display member is a date hand; the date scale comprises the numbers 1 to 31 and / or indexes corresponding to the numbers, the successive numbers from 1 to 31 being separated by the first angle α and the numbers 31 and 1 being separated by the second angle β greater than said first angle α;the first wheel has 31 teeth and is configured to make one revolution in 31 days, and the anterograde display mechanism is configured to progressively wind the elastic member over 31 days; the display has a minute or second graduation with 60 markers, and the display member is a minute or second hand respectively. ;

[0012] The invention also relates to a clockwork movement characterized in that it comprises an anterograde display mechanism according to the invention.

[0013] The invention also relates to a timepiece comprising a timepiece movement setting in motion an anterograde display mechanism according to the invention.

[0014] Preferably, the timepiece is a wristwatch. Brief description of the figures

[0015] The aims, advantages and characteristics of the present invention will appear on reading the detailed description below with reference to the following figures: there figure 1 is a schematic perspective representation of a first exemplary embodiment of an anterograde display mechanism according to the invention; figure 2 is a schematic representation in bottom view of the anterograde display mechanism illustrated in figure 1 ; THE figures 3 to 6 schematically illustrate different positions of the anterograde display mechanism shown in figure 1 ; THE Figures 7a and 7b schematically illustrate a second example of embodiment of the anterograde display mechanism according to the invention, and more particularly a second example of embodiment of a display dial at the Figure 7a and a second example of embodiment of a corresponding display wheel, at the Figure 7b ; THE Figures 8a and 8bschematically illustrate a third example of embodiment of the anterograde display mechanism according to the invention, and more particularly a third example of embodiment of a display dial at the Figure 8a and a third example of embodiment of a corresponding display wheel, at the Figure 8b ; THE Figures 9a and 9b schematically illustrate a fourth example of embodiment of the anterograde display mechanism according to the invention, and more particularly a fourth example of embodiment of a display dial at the Figure 9a and a fourth example of embodiment of a corresponding display wheel, at the Figure 9b .

[0016] In all figures, common elements bear the same reference numbers unless otherwise specified. Detailed description of the invention

[0017] The anterograde display mechanism 100 according to the invention is intended to be housed in a timepiece, for example in a wristwatch.

[0018] The anterograde display mechanism 100 according to the invention is configured to be driven by a clockwork movement (not shown), that is to say by a mechanism whose operation depends on the division of time.

[0019] The anterograde display mechanism 100 is configured to perform a jump display of a display member (or indicator), for example a needle, opposite a display, for example a dial, having a peripheral graduation formed by a plurality of marks distributed over a circumference of the display, the angular distance separating two of these consecutive marks corresponding to a second angle β greater than a first angle α separating two of the other consecutive marks of the graduation. The graduation comprises at least two consecutive marks separated by a second angle β greater than a first angle α.

[0020] In an alternative embodiment (not shown), the anterograde display mechanism 100 is configured to perform a jump display of a display member, for example a disc having a plurality of marks, forming a peripheral graduation, distributed over a circumference of the disc, cooperating with an opening provided in a dial forming a window revealing a portion of the display member.

[0021] The anterograde display mechanism 100 is configured to drive the display member by successive short jumps between the marks of the graduation separated by the first angle α and by a long jump between the two consecutive marks of the graduation separated by the second angle β.

[0022] In a first example of embodiment of the anterograde display mechanism 100 illustrated particularly in figures 1 to 6, the anterograde display mechanism 100 is applied to a particular example of a date display. However, the anterograde display mechanism according to the invention is also applicable for the display of any information derived from time. Thus, the anterograde display mechanism according to the invention can also be an anterograde display mechanism for the date, hour, minute, second, or even for a chronograph, moon phase, counter, power reserve, etc.

[0023] In the first example shown in figures 1 to 6 , the anterograde display mechanism 100 comprises a dial 3 (shown on the figures 3 to 6 ) bearing a plurality of markers forming a date graduation. Dial 3 therefore has 31 markers distributed around the circumference of dial 3.

[0024] In the example shown, the date scale comprises the odd numbers 1 to 31 distributed over a circumference of the dial 3 as well as indexes located between two odd numbers. The indexes located between the odd numbers here represent even numbers. They replace the numbers of the scale in particular for better readability of the display. Thus, in the present application, for greater clarity, we will only speak of numbers, the even numbers here being indexes.

[0025] The angular distance separating the consecutive digits 31 and 1 corresponds to a second angle β larger than a first angle α separating the other digits between 1 and 31 of the date scale.

[0026] There figure 1illustrates a schematic perspective view of the anterograde display mechanism 100 according to the invention making it possible to drive the display member in its angular movements by successive short jumps between the marks separated by an angle α and by a long jump between the marks of the graduation separated by an angle β.

[0027] There figure 2 schematically illustrates a bottom view of the anterograde display mechanism 100 shown in figure 1 .

[0028] In reference to the figures 1 And 2 , the anterograde display mechanism 100 according to the invention comprises a first wheel 110, called the drive wheel, driven in rotation directly by the clockwork movement (not shown).

[0029] In the embodiment shown, the rotational speed of the drive wheel 110 is 1 revolution in 31 days, and the drive wheel is set in motion once a day by the clockwork. The drive wheel 110 therefore advances one step per day.

[0030] For this purpose, the drive wheel 110 has a number of teeth n 1, here equal to 31 teeth for 31 indexing positions of the driving wheel 110 corresponding to 31 indexed positions of the date display member, opposite the 31 marks of the date graduation of dial 3.

[0031] Each indexing position of the drive wheel 110 is indexed by a jumper 180 cooperating with the drive wheel 110. The jumper 180 is rotatable about a pivot 181 and constrained by an elastic element (not shown) tending to bring a jumper beak 182 back towards the axis of rotation of the drive wheel 110, so that the jumper beak 182 cooperates with the teeth and the inter-tooth spaces of the drive wheel 110 to ensure that the drive wheel 110 is maintained in the indexing position between each step.

[0032] The anterograde display mechanism 100 further comprises a second wheel 120 mounted coaxially with the drive wheel 110. The second wheel 120 has a number of teeth n 2 different from the number of teeth n 1 of the drive wheel 110. Advantageously, the second wheel 120 has a number of teeth n 2 greater than the number of teeth n 1 of the 110 drive wheel.

[0033] The matrix wheel 110 and the second wheel 120 are not integral in rotation. The two wheels 110, 120 are connected to each other by an elastic member 160. The elastic member 160 comprises a first end 161 integral with the drive wheel 110 and a second end 162 integral with the second wheel 120.

[0034] By solidary we mean a mechanical connection of which at least one degree of freedom is blocked.

[0035] The anterograde display mechanism 100 further comprises a third wheel 130, called the display wheel, which drives the display member making it possible to display the date on a dial 3.

[0036] For example, as represented in figures 3 to 6 , the display member can be formed by a date hand 2 mounted on a barrel 132 of the display wheel 130.

[0037] According to an alternative embodiment (not shown), the display member is a disc integral in rotation with the display wheel 130, the disc having a plurality of marks forming the date graduation, and being configured to cooperate with an opening in the dial to reveal a portion of the disc.

[0038] The drive wheel 110 directly drives an intermediate wheel 150, which directly drives the display wheel 130. The intermediate wheel 150 advantageously makes it possible to provide a return between the drive wheel 110 and the display wheel 130.

[0039] The display wheel 130 comprises at least one toothed portion and at least one angular sector 131 in which a plurality of teeth are truncated so as to form a “smooth” angular sector without teeth. Thus, momentarily, at each complete rotation of the display wheel 130, the display wheel 130 is no longer directly engaged with the drive wheel 110 when the smooth angular sector 131 of the display wheel 130 is opposite the teeth of the intermediate wheel 150.

[0040] In the particular case illustrated in figures 1 to 6 , the smooth angular sector 131 is bordered by a first tooth d1 of the toothing and by a last tooth d30 of the toothing, the display wheel 130 comprising 30 teeth.

[0041] In the example shown in figures 1 to 6 , the display wheel 130 comprises a single smooth angular sector 131 defining an area in which at least two teeth are truncated.

[0042] Thus, the display wheel 130 has an effective number n 3 eff of teeth distributed over the toothed portion and a number n 3 trunk of truncated teeth on the smooth angular sector 131. We thus obtain a number n 3 horse corresponding to an equivalence of teeth on the circumference of the wheel.

[0043] For display wheel 130, we have the following relationship: n 3 equi = n 3 eff + n 3 tronq

[0044] It will be noted that the display wheel 130 may also comprise several toothed portions and several smooth angular sectors 131, having a more or less significant angular distance, an equal or unequal angular distance, which may be distributed uniformly, or not, on the circumference of the display wheel 130, depending on the requirements. Other exemplary embodiments will be described subsequently with reference to FIGS. 7 to 10.

[0045] The anterograde display mechanism 100 further comprises a fourth wheel 140 coaxial with the display wheel 130 and integral in rotation with the display wheel 130. The fourth wheel comprises a number of teeth n 4 .

[0046] The fourth wheel 140 meshes directly with a second intermediate wheel 170 which meshes directly with the second wheel 120, so that the second wheel 120 is rotated by the second intermediate wheel 170.

[0047] Advantageously, the second wheel 120 has a number of teeth n 2 greater than the number of teeth n 1 of the drive wheel 110, so as to have a rotation speed lower than the rotation speed of the drive wheel 110, and thus progressively arm, or load, the elastic member 160 during the rotation of the drive wheel 110.

[0048] Advantageously, the second wheel 120 and the display wheel 130 respectively have a number of teeth n 2 , n 3 horse greater than the number of teeth n 1 of the drive wheel 110. Advantageously, the second wheel 120 and the display wheel 130 have the same number of teeth ( n 2 = n 3 horse ) .

[0049] Advantageously, the second wheel 120, the display wheel 130, and the fourth wheel 140 respectively have a number of teeth n 2 , n 3 horse , n 4 greater than the number of teeth n 1 of the drive wheel 110. Advantageously the second wheel 120, the display wheel 130, and the fourth wheel 140 have the same number of teeth ( n 2 = n 3 horse = n 4) .

[0050] In the example embodiment illustrated in figures 3 to 6, dial 3 bears the date graduation. The date graduation has 31 marks which are not distributed uniformly around the circumference of dial 3, since the second angle β between the number 31 and 1 is greater than the first angle α separating the other numbers between 1 and 31.

[0051] In this example, angle β is twice as large as angle α.

[0052] Thus, quadrant 3 is divided into 32 equidistant divisions, two consecutive divisions of which are separated by the first angle α.

[0053] These divisions form indexable positions P x , with x ranging from 1 to 32.

[0054] The 31 numbers forming the date graduation markers are distributed across 31 indexable positions on dial 3, positions P 1 to P 31.

[0055] The indexable position P 32 (fictitious, therefore represented in dotted lines) has no reference mark and is intended to be directly jumped by the date hand 2 making a long jump of angle β between the number 31 (indexable position P 31) and the number 1 (indexable position P 1).

[0056] The drive wheel 110 has 31 teeth corresponding to the 31 indexed positions of the date hand 2, and therefore 31 marks on the dial 3 of the date graduation.

[0057] Advantageously, the second wheel 120 has a number of teeth n 2 defined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 Or : α is a first angle corresponding to a first angular distance separating at least two following marks of the graduation, β i is a second angle, greater than the first angle α, corresponding to a second angular distance, different from the first angular distance, separating at least two other marks of the graduation following each other at the level of a sector If of the graduation, i is an integer between 1 and j; j is an integer corresponding to the total number of sectors If of the graduation where two following graduation marks are spaced by a second angle β i greater than the first angle α.

[0058] As seen previously, the second angle β is twice as large as the first angle α. n 1 = 31 β / α = 2 n 2 = 32 = n 3 equi = n 4

[0059] The number n 3 trunk of truncated teeth at the smooth angular sector 131 of the display wheel 130 is equivalent to the ratio between the second angle β and the first angle α . n 3 tronq = β α

[0060] Thus, in the embodiment shown in figures 1 to 6 , the display wheel 130 is equivalent to a 32-tooth wheel on which two consecutive teeth are truncated at the smooth angular sector 131. The display wheel 130 therefore has 30 effective teeth n 3 eff .

[0061] For a complete rotation of the drive wheel 110, the second wheel 120 will have an angular delay of 1 / 32° relative to the drive wheel 110 which makes one revolution in 31 days. The difference in relative rotation speed between the drive wheel 110 and the second wheel 120 will progressively load, or arm, the elastic member 160, by elastic deformation, throughout a given period, here 31 days.

[0062] The elastic member 160 may be a leaf spring, a strip, a flat spring, a spiral spring or any other elastic element conventionally used in the field of watchmaking.

[0063] In the example embodiment illustrated in figures 1 to 6 , the elastic member 160 is integral with the drive wheel 110. Consequently, the first end 161 is in one piece with the drive wheel 110 and the second end 162 is connected to the second wheel 120.

[0064] By way of example, the second end 162 forms a hooking head comprising a pin 163 cooperating with an oblong loop 121 provided on the second wheel 120 to secure in rotation the second end 162 of the elastic member 160 to the second wheel 120.

[0065] According to an alternative embodiment not shown, the elastic member is integral with the second wheel 120, so that the second end 162 is in one piece with the second wheel 120 and the first end 161 is connected to the drive wheel 110. How the anterograde display mechanism works

[0066] The operation of the anterograde display mechanism 100 according to the invention will be described below with reference to figures 3 to 6 , representing the operation of the first exemplary embodiment described with reference to figures 1 to 2 .

[0067] There figure 3 illustrates the anterograde display mechanism 100 when the date hand 2 is indexed to the number 1 of the date graduation of the dial 3, corresponding to the indexable position P 1 .

[0068] From this initial position of the anterograde display mechanism 100, the display wheel 130 is driven by the drive wheel 110 for 31 days, at each step of the drive wheel 110. During this period of 31 days, the date hand 2 is moved angularly once a day by successive short jumps of angle α. The date hand 2 is therefore indexed day after day at the different marks of the date graduation corresponding to the different divisions, or indexable positions P x , of the dial 3 separated by an angle α; that is to say between the numbers 1 and the number 31, until reaching the number 31 of the date graduation of the dial 3 (position P 31 ), as illustrated in figure 4 .

[0069] During this period of 31 days, the gear ratio between the driving wheel 110 and the other wheels 120, 130, 140 of the mechanism generates an angular offset between the driving wheel 110 and the second wheel 120. This offset, increasing with each increment by the driving wheel 110, will progressively load the elastic member 160.

[0070] When the date hand 2 is indexed to position P 31 of dial 3 (number 31 of the date scale), the relative angular difference between the driving wheel 110 and the second wheel 120 is maximum, and the elastic member 160 is in its maximum armed position.

[0071] Conversely, as illustrated in the figure 3 , when the date hand 2 is indexed to the indexable position P 1 of the dial 3 (number 1 of the date graduation), the relative angular difference between the driving wheel 110 and the second wheel 120 is minimal, and the elastic member 160 is in its unloaded position.

[0072] After indexing the display member to the indexable position P 31, illustrated in figure 4 , the next step of the drive wheel 110 causes the display wheel 130 to rotate further until it reaches a position where the smooth angular sector 131 is opposite the intermediate wheel 150, so that the display wheel 130 is no longer engaged with the drive wheel 110, as illustrated in Figure 5 . Since the display wheel 130 is momentarily no longer meshed with the drive wheel 110, the elastic member 160 is free to discharge the energy accumulated during the previous 31 days.

[0073] Under the discharge of the elastic member 160, the second wheel 120 tends to catch up with its angular delay accumulated during the previous 31 days, relative to the driving wheel 110, and drives the display wheel 130 in rotation (in the same direction of rotation as the driving wheel 110) so as to advance the date hand 2 forward (in the clockwise direction) until it passes the smooth angular sector 131 and until the intermediate wheel 150 comes into contact with the tooth d1 bordering the smooth angular sector 131, as illustrated in figure 6 .

[0074] The unloading of the elastic member occurs instantly while the drive wheel 110 has not yet completed its rotation corresponding to the daily angular step. This phase is notably illustrated by the figure 6 In this figure, we notice that the date hand 2 is not yet opposite the marker 1 of dial 3.

[0075] Indeed, at this stage, the pitch of the driving wheel 110 is not yet complete because the jumper 180 is not yet positioned between two teeth of the driving wheel 110. With the restoring force of the elastic element acting on the jumper 180, the jumper 180 tends to finalize the rotation of the driving wheel 110 to the next indexing position. The additional rotation of the driving wheel 110 under the effect of the jumper 180 will make it possible to shift the first intermediate wheel 150 and therefore the display wheel 130 to finalize the jump of the date hand 2 and bring the date hand 2 opposite the number 1 of the date graduation of the dial 3, as illustrated in figure 3 previously described.

[0076] Thus, the long jump of angle β of the date hand 2 between the number 31 and the number 1 of the date graduation corresponds to the rotation of angle α conventionally generated by the daily step of the drive wheel 110 and by the unloading of the elastic member 160 causing an additional rotation of an angle ε = β - α to directly reach the number 1 on the date scale.

[0077] Of course, the rotation of the display wheel 130 and therefore of the date hand 2 due to the discharge of the elastic member 160 depends on the energy accumulated during the previous indexing period and on the angular distance of the smooth angular sector 131 of the display wheel 130. Thus, different configurations are possible, and the long jump of angle β can be greater than twice the angle α. Implementation variants

[0078] THE Figures 7a and 7billustrate a second example of embodiment of the anterograde display mechanism according to the invention for displaying a date. The Figure 7a illustrates a second example of the production of a dial 3 bearing a date graduation, and the Figure 7b illustrates a second example of the embodiment of a corresponding display wheel.

[0079] In this second embodiment, dial 3 is divided into 35 equidistant divisions, two consecutive divisions of which are separated by the first angle α.

[0080] These divisions form indexable positions P x , with x ranging from 1 to 35.

[0081] The 31 numbers forming the date graduation markers are distributed at the level of 31 indexable positions P x of dial 3, positions P 1 to P 15 and positions P 16 to P 35.

[0082] In this embodiment, four successive indexable divisions or positions of dial 3, here positions P 16 to P 19 are fictitious and do not have a date marker. Consequently, these divisions are not intended to be indexed by date hand 2.

[0083] In fact, between the number 15 and the number 16, the date hand 2 here makes a long jump of angle β, going from the number 15 (indexable position P 15 ) to the number 16 (indexable position P 20 ), five times greater than the angle α between the other numbers of the date graduation.

[0084] The drive wheel 110 has 31 teeth corresponding to the 31 indexed positions of the date hand 2, and therefore 31 marks on the dial 3 of the date graduation.

[0085] The second wheel 120 has a number of teeth n 2 defined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 , with j = i = 1 n 2 = 31 + 5 − 1 = 35

[0086] Thus, in this second exemplary embodiment, the second wheel 120 and the fourth wheel have 35 teeth, and the display wheel 130 is equivalent to a 35-tooth wheel.

[0087] The number of truncated teeth n 3 trunk at the level of the smooth angular sector 131 of the display wheel 130 is equal to 5: n 3 tronq = β α = 5

[0088] Therefore, in this second embodiment, the display wheel 130 is equivalent to a 35-tooth wheel on which five consecutive teeth are truncated at the smooth angular sector 131. The display wheel 130 therefore has 30 effective teeth.

[0089] THE Figures 8a and 8b illustrate a third example of embodiment of the anterograde display mechanism according to the invention for displaying the minutes. The Figure 8a illustrates a third example of the embodiment of a dial 3 bearing a graduation of minutes, and the Figure 8billustrates a third example of the embodiment of a corresponding display wheel.

[0090] In this third embodiment, dial 3 is divided into 66 equidistant divisions, two consecutive divisions of which are separated by the first angle α.

[0091] These divisions form indexable positions P x , with x ranging from 1 to 66.

[0092] In this third example of embodiment, the 60 marks of the minute graduation are distributed over 60 indexable positions P x of dial 3, positions P 1 to P 30, and positions P 34 to P 63.

[0093] Dial 3 has two sectors S 1 and S 2 comprising three successive divisions, here positions P 31 to P 33 and P 64 to P 66, which are fictitious and do not have a minute marker. Consequently, these divisions are not intended to be indexed by the minute hand.

[0094] Thus, at the level of the first sector S 1 , between the number 30 and the number 31, the minute hand makes a first long jump of an angle β 1 , four times greater than the angle α corresponding to the short jump between the numbers of the minute scale.

[0095] At the level of the second sector S 2 , between the number 60 and the number 1, the minute hand makes a second long jump by an angle β 2 , four times larger than the angle α corresponding to the short jump between the numbers of the minute scale.

[0096] In this example, the drive wheel has 60 teeth for the 60 minutes indexed by the minute display organ.

[0097] The second wheel 120 has a number of teeth n 2 defined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 , avec j = 2 n 2 = n 1 + β 1 / α − 1 + β 2 / α − 1 n 2 = 60 + 4 − 1 + 4 − 1 = 66

[0098] Thus, in this third embodiment, the second wheel 120 and the fourth wheel have 66 teeth, and the display wheel 130 is equivalent to a 66-tooth wheel.

[0099] The display wheel 130, illustrated in Figure 8b , here comprises two smooth angular sectors 131a, 131b opposite each other to allow the indexing of the display member at the level of the minute graduation of the dial 3 illustrated in the Figure 8a , as well as the short jumps of angle α and the two long jumps of angle β 1 and β 2 .

[0100] The number n 3 trunk of truncated teeth at the level of the first smooth angular sector 131a of the display wheel 130 is equal to 4: n 3 tronq = β 1 α = 4

[0101] The number n' 3 trunk of truncated teeth at the level of the second smooth angular sector 131b of the display wheel 130 is equal to 4: n ′ 3 tronq = β 2 α = 4

[0102] Therefore, in this third embodiment, the display wheel 130 is equivalent to a 66-tooth wheel on which four consecutive teeth are truncated at a first smooth angular sector 131a and four consecutive teeth are truncated at a second smooth angular sector 131b.

[0103] The display wheel 130 therefore has 58 effective teeth, i.e. 29 consecutive teeth between each smooth angular sector 131a, 131b, i.e. 29 consecutive teeth on a first toothed portion and 29 consecutive teeth on a second toothed portion.

[0104] THE Figures 9a and 9b illustrate a fourth example of embodiment of the anterograde display mechanism according to the invention, in particular the display of the minutes. The Figure 9a illustrates a fourth example of the production of a dial 3 bearing a minute scale, and the Figure 9b illustrates a fourth example of the embodiment of a corresponding display wheel.

[0105] In this fourth embodiment, dial 3 is divided into 68 equidistant divisions, two consecutive divisions of which are separated by the first angle α.

[0106] These divisions form indexable positions P x , with x ranging from 1 to 68.

[0107] In this fourth example of realization, the 60 marks of the minute graduation are distributed over 60 indexable positions P x.

[0108] Dial 3 has four sectors S 1 , S 2 , S 3 and S 4 of two successive divisions, here the positions P 16 , P 17 , P 33 , P 34 , P 50 , P 51 , P 67 , P 68 , which are fictitious and do not have a minute marker. Consequently, these divisions are not intended to be indexed by the minute hand.

[0109] Thus, at the level of the first sector S 1 , between the number 15 and the number 16, the minute hand makes a first long jump of an angle β 1 , three times larger than the angle α corresponding to the short jump between the numbers of the minute scale.

[0110] At the level of the second sector S 2 , between the number 30 and the number 31, the minute hand makes a second long jump by an angle β 2 , three times larger than the angle α corresponding to the short jump between the numbers of the minute scale.

[0111] At the level of the third sector S 3 , between the number 45 and the number 46, the minute hand makes a third long jump by an angle β 3 , three times larger than the angle α corresponding to the short jump between the numbers of the minute scale.

[0112] At the level of the fourth sector S 4 , between the number 60 and the number 1, the minute hand makes a fourth long jump by an angle β 4 , three times larger than the angle α corresponding to the short jump between the numbers of the minute scale.

[0113] In this example, the drive wheel has 60 teeth for the 60 minutes indexed by the minute display organ.

[0114] The second wheel 120 has a number of teeth n 2 defined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 , avec j = 4 n 2 = n 1 + β 1 / α − 1 + β 2 / α − 1 + β 3 / α − 1 + β 4 / α − 1 n 2 = 60 + 3 − 1 + 3 − 1 + 3 − 1 + 3 − 1 = 68

[0115] Thus, the second wheel 120 and the fourth wheel have 68 teeth, and the display wheel 130 is equivalent to a 68-tooth wheel.

[0116] The display wheel 130, illustrated in Figure 9b, here comprises four smooth angular sectors 131a, 131b, 131c, 131d distributed equidistantly on the display wheel 130 to allow the indexing of the display member at the level of the minute graduation of the dial 3 illustrated in the Figure 9a , as well as the short jumps of angle α and the four long jumps of angle β 1 , β 2 , β 3 , β 4 .

[0117] The number of truncated teeth n 3 trunk at the level of the first smooth angular sector 131a of the display wheel 130 is equal to 3: n 3 tronq = β 1 α = 3

[0118] The number of truncated teeth n' 3 trunk at the level of the second smooth angular sector 131b of the display wheel 130 is equal to 3: n ′ 3 tronqu = β 2 α = 3

[0119] The number of truncated teeth n" 3 trunk at the level of the third smooth angular sector 131c of the display wheel 130 is equal to 3: n " 3 tronq = β 3 α = 3

[0120] The number of truncated teethn‴ 3 trunk at the level of the fourth smooth angular sector 131d of the display wheel 130 is equal to 3: n ‴ 3 tronq = β 4 α = 3

[0121] Therefore, in this fourth embodiment, the display wheel 130 is equivalent to a 68-tooth wheel on which three consecutive teeth are truncated at four smooth angular sectors 131a, 131b, 131c, 131d.

[0122] The display wheel 130 therefore has 56 effective teeth, i.e. 14 consecutive teeth between each smooth angular sector 131a, 131b, 131c, 131d. Thus, the display wheel 130 comprises a first toothed portion of 14 teeth, a second toothed portion of 14 teeth, a third toothed portion of 14 teeth and a fourth toothed portion of 14 teeth, each of the toothed portions being separated by a smooth angular sector 131a, 131b, 131c, 131d corresponding to an angular sector equivalent to three teeth.

[0123] The invention also relates to a clockwork movement comprising such an anterograde display mechanism.

[0124] The invention also relates to a timepiece, such as a wristwatch comprising such a watch movement.

Claims

1. Anterograde display mechanism (100) for a timepiece including a display (3) having a graduation having a plurality of guide-marks distributed on a circumference of the display (3), the graduation being configured such that the angular distance separating at least two successive guide-marks corresponding to a second angle (β) greater than a first angle (α) separating two of the other successive guide-marks, the anterograde display mechanism (100) being configured to drive a display organ (2) in the angular movements thereof by successive short jumps of an angle (α) between two guide-marks separated by the first angle (α) and by a long jump of an angle (β) between two graduation guide-marks separated by the second angle (β), the anterograde display mechanism (100) being characterised in that it includes: - a first wheel (110), referred to as drive wheel, capable of being driven by a horological movement; - a second wheel (120) coaxial with the first wheel (110) and linked to the first wheel (110) by an elastic organ (160); - a first intermediate wheel (150) driven directly by the first wheel (110) and which directly drives a third wheel (130), referred to as display wheel, cooperating with said display organ (2); said third wheel (130) including a smooth angular sector (131, 131a, 131b, 131c, 131d) where at least two teeth are truncated; - a fourth wheel (140) coaxial and rigidly connected in rotation with the third wheel (130), said fourth wheel (140) meshing said second wheel via a second intermediate wheel (170); the anterograde display mechanism being configured so that the rotational speed of the second wheel (120) is less than the rotational speed of the first wheel (110) when the display organ (2) is driven in the angular movements thereof by successive short jumps of an angle (α) between two guide-marks separated by the first angle (α), so as to progressively wind the elastic organ (160) during these successive short jumps, and so that when the teeth of the intermediate wheel (150) encounter the smooth angular sector (131, 131a, 131b, 131c, 131d) of the third wheel (130), the elastic organ (160) is let down inducing the instantaneous passage of the smooth angular sector (131) and inducing the angular movement by a long jump of an angle (β) of said display organ (2).

2. Timepiece anterograde display mechanism (100) according to the preceding claim characterised in that the first wheel (110) is capable of being driven by jumps by said horological movement.

3. Timepiece anterograde display mechanism (100) according to one of the preceding claims, characterised in that the first wheel (110) includes a number of teeth (n1), the number of teeth (n1) being equal to the number of guide-marks of the graduation of the display (3).

4. Timepiece anterograde display mechanism (100) according to the preceding claim, characterised in that the second wheel (120) includes a number of teeth (n2) greater than the number of teeth (n1) of the first wheel (110).

5. Timepiece anterograde display mechanism (100) according to the preceding claims, characterised in that the third wheel (130) includes an effective number (n3 eff) of teeth distributed on a toothed portion and a number of truncated teeth (n3 tronq, n'3 tronq, n"3 tronq, n‴3 tronq) on the smooth angular sector (131, 131a, 131b, 131c, 131d), the whole forming an equivalent number (n3 equi) of teeth on the full circumference of the third wheel (130), the equivalent number (n3 equi) on the full circumference of the third wheel (130) being equal to the number of teeth (n2) of the second wheel (120).

6. Timepiece anterograde display mechanism (100) according to the preceding claim, characterised in that the number of truncated teeth (n3 tronq, n'3 tronq, n"3 tronq, n‴3 tronq) on the smooth angular sector (131, 131a, 131b, 131c, 131d) of the third wheel (130) is an integer corresponding to the ratio of the second angle (β) over the first angle (α).

7. Timepiece anterograde display mechanism (100) according to one of claims 4 to 6, characterised in that the fourth wheel (140) includes a number of teeth (n4) equal to the number of teeth (n2) of the second wheel (120).

8. Timepiece anterograde display mechanism (100) according to one of claims 4 to 7, characterised in that the number of teeth (n2) of the second wheel (120) is determined by the following relation: n 2 = n 1 + ∑ i = 1 j β i / α − 1 , α is the first angle corresponding to a first angular distance separating at least two successive graduation guide-marks; βi is the second angle, greater than the first angle α, corresponding to a second angular distance, different from the first angular distance, separating at least two other successive graduation guide-marks at a sector Si of the graduation; i is an integer between 1 and j ; j is an integer corresponding to the total number of sectors Si of the graduation where two successive graduation guide-marks are spaced apart by a second angle βi greater than the first angle α.

9. Timepiece anterograde display mechanism (100) according to one of claims 1 to 8, characterised in that the elastic organ (160) is a strip spring, a sheet, a flat spring, or a spiral spring.

10. Timepiece anterograde display mechanism (100) according to one of claims 1 to 9, characterised in that the elastic organ (160) is integral with the first wheel (110) such that it includes a first one-piece end (161) with said first wheel (110) and a second end (162) connected to the second wheel (120), or the elastic organ (160) is integral with the second wheel (120) such that it includes a first one-piece end with said second wheel (120) and a second end connected to the first wheel (120).

11. Timepiece anterograde display mechanism (100) according to one of claims 1 to 10, characterised in that the display (3) includes a date graduation with 31 guide-marks and in that the display organ (2) is a date hand.

12. Timepiece anterograde display mechanism (100) according to the preceding claims, characterised in that the date graduation comprises the numerals 1 to 31 and / or indexes corresponding to the numerals, the successive numerals from 1 to 31 being separated by the first angle (α) and the numerals 31 and 1 being separated by the second angle (β) greater than said first angle (α).

13. Timepiece anterograde display mechanism (100) according to the preceding claims, characterised in that the first wheel (110) includes 31 teeth and is configured to perform one turn in 31 days, and in that the anterograde display mechanism is configured to progressively wind the elastic organ (160) for 31 days.

14. Timepiece anterograde display mechanism (100) according to one of claims 1 to 10, characterised in that the display (3) includes a minute or second graduation with 60 guide-marks, and in that the display organ is a minute or second hand respectively.

15. Horological movement characterised in that it comprises a display mechanism (100) according to one of claims 1 to 14.

16. Timepiece including a horological movement comprising an anterograde display mechanism (100) according to one of claims 1 to 15.

Images