EP1070996B1 - Timepiece with date display - Google Patents

Description

The present invention relates to a timepiece with a date display by means of two disks respectively bearing the signs forming the units and the tens.

A piece of this type is described in patent CH 310 559. The two discs are then placed side by side at the same level. Such a structure makes it possible to have figures of greater dimension than with a single date disc, while reducing the area occupied on the movement.

By superimposing the two disks, as described in patent applications EP 529 191 and CH 113 755, it is possible to further reduce the area occupied. When the upper disk is metal or any other opaque material, it must, of course, have cutouts so that the lower disk is visible through them, which weakens and increases the risk of deformation. It is therefore essential to take extra precautions during manufacture and to provide a large space between the two discs, to avoid any risk of friction. The two figures displaying the date are therefore at two different levels. The one farthest from the surface of the dial is necessarily less illuminated than the other, which affects the aesthetics of the watch.

In addition, and in both of the examples given above, there is necessarily a mark between the two signs, which affects both the aesthetics and the quality of the reading of the date.

The present invention is essentially to overcome these disadvantages and, more specifically, to allow a date display that is both large and homogeneous structure.

• deux disques rotatifs au moins partiellement superposés, le disque supérieur étant transparent, qui portent respectivement, régulièrement répartis sur un anneau périphérique, la série des signes formant les unités du quantième et la série des signes formant les dizaines et qui coopèrent pour présenter lesdits signes en juxtaposition, et
• un mécanisme d'entraînement desdits disques en rotation de manière à ce que lesdits signes juxtaposés fournissent une indication du quantième.

More specifically, the invention relates to a timepiece with a date display, which is characterized in that it comprises:

• two rotary disks at least partially superimposed, the upper disk being transparent, which respectively bear, regularly distributed on a peripheral ring, the series of signs forming the units of the date and the series of signs forming the tens and which cooperate to present said signs in juxtaposition, and
• a mechanism for driving said rotating discs so that said juxtaposed signs provide an indication of the date.

Advantageously, the signs carried by the upper disk are arranged on its lower face and that the signs carried by the lower disk are arranged on its upper face. These signs are thus in planes very close to each other and the light travels practically the same way, thanks to which their appearance is almost identical.

The axes of rotation of the disks are preferably separated by a distance substantially equal to r ₁ + r ₂ - 2e, r ₁ and r ₂ being the radii of the disks and e the width of the ring bearing the signs.

Moreover, in order to obtain a reading quality as good as possible, the transparent top disc is provided with an anti-reflective surface treatment.

• une roue effectuant un tour en vingt-quatre heures,
• une roue de commande formée de deux planches superposées et comportant chacune une denture dont le pas est égal à 1/31 ème de leur diamètre primitif,
• deux pignons respectivement solidaires des deux disques, comportant autant de dents qu'ils ont de signes et engrenant avec lesdites planches, et
• des moyens d'accouplement de la roue de vingt-quatre heures avec ladite roue de commande pour la faire tourner d'un pas par jour.

According to a preferred embodiment, the drive mechanism comprises:

• a wheel making a turn in twenty-four hours,
• a control wheel formed of two superimposed planks and each having a toothing whose pitch is equal to 1/31 th of their original diameter,
• two pinions respectively integral with the two discs, having as many teeth as they have signs and meshing with said boards, and
• means for coupling the twenty-four hour wheel with said control wheel to rotate it one step per day.

Advantageously, the plate engaged with the disk gear of the units comprises thirty teeth and a space, while the board engaged with the pinion of the tens disk has four teeth and twenty-seven spaces distributed according to the sequence: nine spaces - one tooth - nine spaces - one tooth - nine spaces - one tooth - one space, one tooth.

• une goupille portée par la roue de vingt-quatre heures, et
• une détente comprenant un sautoir coopérant avec la planche de la roue de commande en prise avec le disque des unités et muni de deux bossages distants l'un de l'autre d'une valeur égale au pas de la denture de cette planche, une structure d'entraînement coopérant avec ladite goupille et un organe élastique portant ledit sautoir et ladite structure,

cet agencement étant tel qu'à chaque arrivée de la goupille contre la structure d'entraînement, la séquence des mouvements suivants est enclenchée:

• le sautoir se désolidarise de sa planche,
• l'organe élastique est armé,
• le sautoir engrène de nouveau avec ladite planche, et
• la structure d'entraînement se libère de la goupille, permettant ainsi le désarmage de l'organe élastique et l'avance d'un pas de la planche sous l'action du sautoir.

Finally, the coupling means of the twenty-four hour wheel with the control wheel comprise:

• a pin carried by the twenty-four hour wheel, and
• an expansion comprising a jumper cooperating with the board of the control wheel engaged with the disk units and provided with two bosses spaced from each other by a value equal to the pitch of the toothing of this board, a structure driving cooperating with said pin and an elastic member carrying said jumper and said structure,

this arrangement being such that at each arrival of the pin against the driving structure, the sequence of the following movements is triggered:

• the jumper dissociates itself from its board,
• the elastic member is armed,
• the jumper meshes again with said board, and
• the drive structure is released from the pin, thereby disarming the elastic member and advance one step of the board under the action of the jumper.

• la figure 1 est une vue partielle en plan d'une pièce d'horlogerie selon l'invention,
• la figure 2 montre les organes qui assurent l'entraînement des deux disques, ceux-ci étant représentés en écorché sans leurs signes; et
• la figure 3 est une vue en coupe selon la ligne lll-lll de la pièce représentée à la figure 1.

Other advantages and features of the invention will emerge from the description which follows, given with reference to the appended drawing, in which:

• FIG. 1 is a partial plan view of a timepiece according to the invention,
• Figure 2 shows the bodies that drive the two discs, they are represented in cutaway without their signs; and
• Figure 3 is a sectional view along the line III-III of the part shown in Figure 1.

The timepiece represented in the drawing, in this case a watch movement, comprises a plate 10 intended to serve as a support, in particular, a date mechanism. The latter comprises two disks 14 and 16, of the same radius r , each carrying, on a peripheral ring of width e , a series of signs 14a and 16a allowing the display of the tens and the date units, respectively.

The tens disk 14 is slightly lower than the disk of the units 16 and carries, in a conventional manner the signs 14a, regularly distributed in the number of 8, which form twice the sequence 0 (or a white space), 1, 2 3. It may be, for example, metal, opaque plastic or other transparent material (plastic, glass or sapphire) coated with an opaque layer on its underside.

The disc of the units 16 carries, also in a conventional manner, the signs 16a, regularly distributed in the number of 10, which form the sequence of the digits from 0 to 9. It is necessarily made of transparent material, such as plastic, glass or sapphire. Advantageously, its upper face is coated with an anti-reflection layer 16c, which improves the readability of the display.

The lower disc 14 and the upper disc 16 pivot about axes parallel to each other on pins 18 and 20 (Figure 3) which they are secured by means of screws 22 and 24.

The two disks 14 and 16 cooperate to present in juxtaposition the signs of their respective rings so as to provide an indication of the date. So that this juxtaposition is carried out correctly, it will be noted that the distance D separating the tenons 18 and 20 must be substantially equal to: $$\mathrm{two}\left(\mathrm{r}\mathrm{-}\mathrm{e}\right)\mathrm{.}$$

The date is read through a dial 26 in which is practiced a window schematically shown in Figure 1 by a rectangle 28.

It is particularly advantageous that the signs 14a of the lower disk are disposed on its upper face but that the signs 16a of the upper disk are arranged on its underside. Thus, the difference in levels between the signs 14a and 16a substantially corresponds to the space between the two disks, which is extremely small, typically from 0.1 to 0.2 mm.

In addition, and as shown in Figure 1, we see that this construction eliminates any unsightly mark between the signs of the two rings. Moreover, with an adequate sizing of the window 28, the edges of the disks are not visible.

Thus, a large-numbered date display 30 is produced under optimum aesthetic conditions.

As best shown in Figures 2 and 3, the drive discs 14 and 16 is provided by means of two pinions 32 and 34 respectively mounted on their axes and under the discs. These gears each have as many teeth as the disk associated with it includes signs. This means that the pinion 32 of the tens disk 14 carries 8 teeth and the pinion 34 of the disk of the units 16 bears 10.

Two identical jumpers 36 and 38 respectively cooperate with the pinions 32 and 34 to position them. As will be described later, these jumpers are mounted adjustable in position to ensure optimal alignment of the signs carried by the two discs.

The pinions 32 and 34 mesh with a control wheel 40 pivotally mounted between them on the plate 10 to which it is fixed by means of a screw 42. It will be noted that the axes of these two gears (and therefore disks 14 and 16 ) and the axis of the control wheel 40 are aligned.

A detent 44, which will be described later in detail, serves to achieve instantaneous date training by acting on the control wheel 40. It is armed by a pin 46 mounted on a wheel of twenty-four 48 hours which makes one turn a day. This is connected to the clockwork in a conventional manner and not shown in the drawing.

As can be seen more particularly in Figure 3, the control wheel 40 is formed of two boards 50 and 52 superimposed respectively provided with a toothing 50a and 52a. The toothing 50a of the upper board meshes with the pinion 32 associated with the lower disk of the tens 14, while the toothing 52a of the lower plate meshes with the pinion 34 associated with the upper disk of the units 16. The two boards are positioned one relative to each other by means of pins 54.

The teeth 50a and 52a have the same module and the same pitch diameter but, as shown in Figure 2, they are incomplete. More precisely, the modulus of these teeth is equal to 1/31 th of their original diameter. Each toothing should have thirty-one teeth but, as can be seen, the toothing 50a has thirty teeth and a space, while the toothing 52a has four teeth and twenty-seven spaces. Such a configuration of the wheel 40 makes it possible to drive the discs 14 and 16 so that they respectively perform 1 half-turn and 3 turns per month, and successively display the numbers 1 to 31, then return to 1.

More precisely, the four teeth and twenty-seven spaces of the lower plank 52 are distributed in the following sequence: nine spaces - a tooth - nine spaces - a tooth - nine spaces - a tooth - a space - a tooth. The two boards are arranged so that the tooth placed after the isolated space of the board 52 meshes with the pinion 34 when the single space of the board 50 is opposite the pinion 32. This position corresponds to the passage of the 31 one month to the 1st of the following month.

• Lorsque le disque des dizaines 14 affiche 0, 1 ou 2 et le disque des unités 16 affiche les chiffres de 0 à 8, la roue 40 n'entraîne que le disque des unités 16, à raison d'un pas par jour, par la denture 52a en prise avec la roue 34.
• Lorsque le disque des dizaines 14 affiche 0, 1 ou 2 et le disque des unités 16 affiche le chiffre 9, les deux disques sont entraînés, les dentures 50a et 52a étant respectivement en prise avec les pignons 32 et 34.
• Lorsque le disque des dizaines 14 affiche le chiffre 3 et le disque des unités 16 affiche le chiffre 0, la situation est la même que dans la première configuration mentionnée ci-dessus. En d'autres termes, seule la denture 50 entraîne la roue 32. L'affichage passe donc de 30 à 31.
• Lorsque le disque des dizaines 14 affiche le chiffre 3 et le disque des unités 16 le chiffre 1, seul le disque des dizaines est entraîné, passant de 3 à 0. En d'autres termes, seule la denture 52a entraîne le pignon 34, le chiffre 1 des unités restant en place et l'affichage passant de 31 à 1.

In this way, the wheel 40 and its boards 50 and 52 meshing, with their teeth 50a and 52a, with the pinions 32 and 34 according to the following four configurations.

• When the tens disk 14 displays 0, 1 or 2 and the disk of the units 16 displays the digits 0 to 8, the wheel 40 drives only the disk of the units 16, at a rate of one step per day, by the gear 52a engaged with the wheel 34.
• When the tens disk 14 displays 0, 1 or 2 and the disk of the units 16 displays the number 9, the two disks are driven, the teeth 50a and 52a respectively being engaged with the pinions 32 and 34.
• When the tens disk 14 displays the digit 3 and the disk of the units 16 displays the digit 0, the situation is the same as in the first configuration mentioned above. In other words, only the toothing 50 drives the wheel 32. The display therefore increases from 30 to 31.
• When the tens disk 14 displays the digit 3 and the disk of the units 16 the number 1, only the tens disk is driven from 3 to 0. In other words, only the toothing 52a drives the pinion 34, the number 1 of the units remaining in place and the display from 31 to 1.

The detent 44 provides the connection between the twenty-four hour wheel 48 and the control wheel 40. It is in the form of a U-shaped metal piece, with three elastic arms 44a, 44b and 44c. It is arranged in the thickness of the movement so as to cooperate on the one hand with the lower board 52 and on the other hand with the pin 46.

The arm 44a ensures the attachment of the detent 44 on the plate 10, by its free end formed of a board 44d pierced with holes 44e for the engagement of a pin and a screw not shown in the drawing. In addition, substantially at the junction between the arms 44a and 44b, there is a structure 44f for the correction of the date, which will be described later.

The arm 44c has, at its free end, a jumper 44g provided with two bosses 44h and 44i engaged with the toothing 52a of the board 52 and, in its middle part, a drive structure formed of a withdrawal plane 44j and a 44k arming finger. This structure cooperates with the pin 46 of the twenty-four hour wheel 48.

Wheel 48 rotates counterclockwise. It is oriented so that at the end of the day, its pin 46 comes to bear against the withdrawal plan 44j. The force it generates then causes a deformation of the trigger 44 so that the jumper 44g away from the toothing 52a, until the bosses 44h and 44i are no longer in contact. This position is reached when the pin 46 completes scanning the withdrawal plane 44j and comes into contact with the finger 44k.

The rotational movement of the pin 46 brings the trigger 44 to the right, with a displacement substantially equal to one step of the wheel 40, then towards the latter until the bosses 44h and 44i enter again into the spaces in between the teeth of the board 52. In this position, the pin 46 can no longer cause the relaxation 44. It is released gradually finger 44k, finally releasing the trigger which then resumes its rest position as shown in drawing, moving to the left and advancing a wheel 40 which, in turn acts on the two gears 32 and 34.

As the toothing 52a is deprived of a tooth, a simple jumper would be problematic when it should cooperate with the part in which the tooth is missing, the support conditions are not the same. It is for this reason that the jumper 44g comprises the two bosses 44h and 44i, which are spaced from each other by a value equal to the pitch of the toothing 52a. There is, in this way, always at least two surfaces of the bosses which cooperate with the toothing 52a to ensure training on an angle corresponding to a step.

The correction of the date is done, in a conventional manner, by means of a time-setting rod (not shown in the drawing) which drives a wheel of correction 56 provided with four pins 58 cooperating with the structure 44f. More specifically, the latter is formed of a withdrawal plane 44l and a finger 44m. The assembly formed by the pins 58 and the structure 44f works identically to the assembly defined by the pin 46, the plane 44j and the finger 44k.

As already mentioned, the two jumpers 36 and 38 are mounted adjustable in position to ensure optimal alignment of the signs carried by the two discs. For this purpose, they comprise a U-shaped body whose two branches, identified by the letters a and b , are extended by a fork c . The branch form spring and engages with its free end, with the gear 32 or 34 to perform the function jumper. Branch b is rigid. Its free end is provided with a cylindrical hole in which is engaged a screw 60, while its other end has an oblong hole provided with a hole, in which is engaged a screw 62. Finally, the fork c cooperates with an eccentric 64. The screws 60 and 62 and the eccentric 64 are fixed in the plate.

To adjust the jumpers 36 and 38, it is sufficient to loosen the screws 62 and then turn the eccentrics 64 to bring the discs 14 and 16 in a rest position for which their respective signs are perfectly aligned. The screws 62 are then tightened to block the jumpers in the proper position.

The tens disk 14, as shown, has two sets of signs 0, 1, 2, 3, which defines 8 positions. In this way, its diameter is substantially the same as that of the disk of the units 16, which has 10 distinct positions. Alternatively, it is also possible to provide a disk 14 having only one series of signs, or 4 distinct positions, so that it can be smaller diameter. In this case, the distance separating the axes of the two disks, of respective radii r ₁ and r ₂ , must be substantially equal to r ₁ + r ₂ - 2e.

This description has been made with reference to an instant-type drive mechanism, but it is obvious that other mechanisms are usable, of trailing or semi-instantaneous type for example, without departing from the scope of the invention.

Moreover, the embodiment described advantageously comprises two disks pivoting about distinct axes, but it would also be possible to arrange them coaxially.

Claims (10)

1. Timepiece with a display of the day of the month comprising:

   - two rotary disks (14, 16) at least partially superposed, which respectively support, evenly distributed over a peripheral ring, the series of signs forming the units of the day of the month and the series of signs forming the tens and that interact to present the said signs in juxtaposition in order to display the day of the month, and

   - a mechanism for rotating the said disks so that the said juxtaposed signs provide an indication of the day of the month (30),

   characterized in that the said top disk (16) is transparent.
2. Timepiece according to Claim 1, characterized in that the signs supported by the top disk (16) are placed on its bottom face and that the signs supported by the bottom disk (14) are placed on its top face.
3. Timepiece according to one of Claims 1 and 2, characterized in that the rotation shafts of the disks are separated by a distance substantially equal to r₁ + r₂ - 2e, r₁ and r₂ being the radii of the disks and e the width of the ring supporting the signs.
4. Timepiece according to one of Claims 1 to 3, characterized in that the top transparent disk is furnished with an antireflective surface treatment.
5. Timepiece according to one of Claims 1 to 4, characterized in that the said drive mechanism comprises:

   - a wheel (48) making one revolution in twenty-four hours,

   - a control wheel (40) formed of two superposed plates (50, 52) and each comprising gear teeth whose pitch is equal to 1/31th of their primitive diameter,

   - two gears (32, 34) respectively fixedly attached to the two disks, comprising as many teeth as the latter have signs and meshing with the said plates, and

   - means of coupling the twenty-four hour wheel with the said control wheel to make it rotate by one pitch per day.
6. Timepiece according to Claim 5, characterized in that:

   - the plate (52) engaged with the gear (34) of the units disk (16) comprises thirty teeth and one space, and

   - the plate (50) engaged with the gear (32) of the tens disk (14) comprises four teeth and twenty-seven spaces distributed in the sequence: nine spaces - one tooth - nine spaces - one tooth - nine spaces - one tooth - one space, one tooth.
7. Timepiece according to one of Claims 5 and 6, characterized in that the said coupling means comprise:

   - a pin (46) supported by the twenty-four hour wheel (48), and

   - a detent (44) comprising a jumper (44g) interacting with the plate (52) engaged with the wheel (34) of the units disk, a drive structure (44j, 44k) interacting with the said pin and an elastic member (44c) supporting the said jumper and the said structure,

   this arrangement being such that each time the pin (46) comes against the drive structure, the sequence of the following movements is engaged:

   - the jumper (44g) separates itself from its plate,

   - the elastic member (44c) is wound,

   - the jumper (44g) again engages with the said plate, and

   - the drive structure releases itself from the pin, thus allowing the elastic member to unwind and the plate to advance by one pitch under the action of the jumper.
8. Timepiece according to Claims 6 and 7, characterized in that the said jumper comprises two bosses (44h, 44i) apart from one another at a distance equal to the pitch of the gear teeth of the units plate (52).
9. Timepiece according to Claim 5, characterized in that each of the said gears (32, 34) is associated with a jumper (36, 38) serving to position it.
10. Timepiece according to Claim 9, characterized in that the said jumper can be positionally adjusted in order to allow an optimal alignment of the signs supported by the disks.

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