EP0756217B1 - Annual calendar mechanism for timepieces - Google Patents

Description

The invention relates to a date mechanism annual for a timepiece, said mechanism comprising a date ring with thirty-one teeth inner to the ring, on which are affixed thirty and a number each corresponding to a date of the month which appear successively through a pierced window in a dial, and a date-driven mobile going around in twenty-four hours, said mobile being equipped with a first finger likely to cause a step and once a day the date ring by one of its internal teeth, said mobile controlling the display of the date.

A date mechanism responding in large lines to the definition that has just been given is known for example documents CH-A-538 136 and CH-A-661 171 (US-A-4,676,659). In these documents, there is also a twenty-four hour driving date wheel fitted a finger or a long tooth which drives a disc of date with thirty-one indications. However, the finger does not directly drive the disc but a mobile intermediary who, him, drives this disc. This is there of course an ordinary calendar mechanism, not an annual one, neither perpetual. At the end of the thirty-day months and at the end of February, it is then necessary to operate a manual correction if you don't want to lose the dated.

A description of different types of mechanisms calendar in watches is given in the book entitled "Modern calendar watches" by B. Humbert - Editions Scriptar S.A. Lausanne 1953 (English version: "Modern calendar watches", Lausanne 1954).

Document DE-A-2 311 539 describes a mechanism for calendar using a month cam rotating by year. This cam has more or less notches deep: the solid parts correspond to the months of thirty-one days; the shallow notches in the months of thirty days, and a very deep notch in the month of February in common years (twenty-eight days). On this cam acts the beak of a lever returned by a spring. The beak penetration depth will determine which advance must be printed on the date indicator by a seesaw at the end of each month.

The mechanism briefly discussed above uses levers and return springs, which leads to a relatively complicated construction which requires its turn a relatively high number of pieces. On the other hand, it will be mentioned that such rocking mechanisms do not not always have safe operation, especially if shocks are applied to the part of watchmaking.

A perpetual calendar mechanism comprising relatively few parts is described in the patent DE 449 081. Several superimposed coaxial discs, bearing respectively the indications of the days, of the date of 1 to 15, from the date 15 to 31, months and years, have respective central openings having teeth, some of which have tooth heights variables. These teeth are attacked by two pawls carried by a driving mobile which swivels back and forth. One of the pawls has a flexible bent end which, in leaning against a height-adjustable toothing which plays the role of cam, attacks or does not attack the second disc date in the last days of the month. The disc months carries a sliding spring which drives the first date disc to turn it back on when change of month. Despite its apparent simplicity, this mechanism is thick, delicate and has not spread. Of the more it requires back-and-forth training, which requires an additional mechanism in a room of watchmaking.

To overcome the aforementioned drawbacks, this invention proposes to use only gears to the exclusion of all levers or rockers, these gears, on the one hand, being prevented from any rotation untimely even if shocks are applied to the part of watchmaking and, on the other hand, having a construction significantly simplified and reduced in height, all the more more than the date of the invention is limited in advance automatic date only for months of thirty days, the date reset must be done manually at the end of February. It is therefore a annual and not perpetual calendar.

An annual calendar in which a correction manual remains necessary at the end of February a already proposed and described in document CH 684 815. In this document, the annual calendar mechanism has a driving date wheel fitted with a finger capable of driving a wheel date at the end of each day. An annual wheel, driven once a month by two paces with a tooth long range by an intermediate wheel meshing itself on the date wheel, has a board bearing five teeth each corresponding to one of the months of less than thirty-one days. When one of these five teeth presents itself on the finger path, the annual wheel, from led as it was, becomes a leader and drives the wheel date by one additional step via the wheel intermediate.

Although clearly constructed simplified and reduced in height compared to a perpetual calendar, the mechanism which has just been described in summary above requires the provision of numerous new parts. It also requires transformation important of a basic movement that one would like modify if possible at lower cost.

To overcome these drawbacks and therefore propose a annual calendar mechanism easily adaptable to a classical movement, at the same time as it requires a minimum of new parts, the present invention is remarkable in that, starting from the characteristics known defined in the first paragraph of this description, the mechanism further includes a crown annual superimposed on the date ring, making a round in one year and fitted with external teeth in positions corresponding to the twelve months of the year and five interior teeth in corresponding positions for months less than thirty-one days, the said crown being arranged eccentrically with respect to the ring and to proximity of the date trainer mobile so that it be activated, at the end of the months under thirty-one days, by a second finger presented by the mobile calendar coach, this second finger acting on one of the five inner teeth of the crown, engagement means integral with the date ring being implemented to engage, at the end of each month, said date ring with said annual crown with at least one of its teeth outside.

The result is a mechanism of which all the mobiles are only three in number, namely the mobile coach, date ring and crown annual. These mobiles can be arranged in two levels only, that of the date ring and that of the annual crown passing above or below this one. It is therefore possible to realize the mechanism of calendar in the form of a thin module, that can be superimposed on an ordinary watch movement. In addition, the eccentric arrangement of the crown annual offer, if this crown has indications months, a great freedom of choice of the position of the counter where these indications appear, in particular at different distances from the center of the watch movement and the dial. In particular the crown can be arranged eccentrically with respect to this center and being big enough to pass around him, that is to say around the needle trees of an analog display classic.

• la figure 1 est une vue en plan d'une montre présentant un quantième annuel selon l'invention,
• la figure 2 est une vue en plan du mécanisme de quantième annuel équipant la montre de la figure 1, cette figure illustrant la situation des rouages le 30 avril à 23 heures 45 minutes,
• la figure 3 est une vue analogue à celle de la figure 2, la situation des rouages étant celle présentée le 1er mai à 0 heure 15 minutes,
• la figure 4 est une vue analogue à celle de la figure 2, la situation des rouages étant celle présentée le 1er mai à 4 heures,
• la figure 5 est une coupe selon la ligne V-V de la figure 2, et
• la figure 6 est une vue en plan de la couronne annuelle de la figure 2 qui explicite la fonction de cette couronne par rapport aux mois de l'année.

The invention will now be explained with the aid of the description which follows and of the drawings which illustrate it by way of example, in which:

• FIG. 1 is a plan view of a watch presenting an annual calendar according to the invention,
• FIG. 2 is a plan view of the annual calendar mechanism fitted to the watch in FIG. 1, this figure illustrating the situation of the workings on April 30 at 11:45 pm,
• FIG. 3 is a view similar to that of FIG. 2, the gear train situation being that presented on May 1 at 0 hours 15 minutes,
• FIG. 4 is a view similar to that of FIG. 2, the gear situation being that presented on May 1 at 4 a.m.,
• FIG. 5 is a section along the line VV in FIG. 2, and
• Figure 6 is a plan view of the annual crown of Figure 2 which explains the function of this crown in relation to the months of the year.

The plan view of Figure 1 shows a watch equipped, apart from the hour hands 70, minutes 71 and 72 seconds, a date indicator under the form of a date 3 appearing through a window 4 pierced in a dial 5. The time setting can be performed by means of the crown 61. If we get rid of now this watch from its dial and that we don't keep that the elements useful in carrying out the invention, we end up to the plan views of FIGS. 2, 3 and 4 which show the mechanism in question at three different times during the transition from April to May.

Examination of figure 2 and the section of figure 5 in particular will explain the date mechanism annual according to the invention. This mechanism has a ring date 1 with thirty-one teeth 2. On the ring 1 are affixed thirty-one corresponding digits 3 each on a date of the month. These numbers appear successively through the window 4 pierced in the dial 5 shown in Figure 1. A moving coach of date, generally designated by reference 6, is equipped with a first finger 7 likely to cause a step and once a day the date ring 1 by one of its inner teeth 2. In the particular case shown in FIG. 2, the first finger 7 has just entered contact with tooth 2a and will therefore advance the ring 1 of a step from 30 to 31 as it is finally shown at Figure 3. As seen in Figures 2 to 4 and better still on the section of figure 5, the mobile coach 6 comprises a coach wheel 21 which connects this mobile to the watch movement (not shown here) and make a tour in twenty-four hours. Figure cut 5 shows that the first finger 7 of the mobile coach 6 is on the way to tooth 2a belonging to the date ring 1. The finger 7 is a outgrowth of a disc 22 forced on a shaft 23, the wheel coach 21 being integral with the same shaft 23. By its pivot 24, the shaft 23 can rotate freely in a bearing 25 set in the plate 17 of the timepiece.

What was described in the above paragraph is good known from the state of the art. It’s actually the classic training of a date ring, this ring which can be reset by a corrector fast 20 (see figure 2) engaged on teeth 2 of ring 1, this corrector 20 being controlled by the manual crown 61 (figure 1). In this classic system resetting is necessary at the end of the month counting less than thirty-one days, i.e. the months of February, April, June, September and November.

We will now describe what has been added to this classic mechanism to transform it, according to the invention, in an annual mechanism in the sense that the date jumps from 30 to 1 at the end of the months under thirty-one days.

In addition to what has been listed above, the mechanism according to the invention comprises an annual crown 8 having an annular shape, as drawn on the Figures 2 to 6. This crown is superimposed on the ring of date 1 and do a tour in one year. Crown 8 has twenty-four teeth 9 uniformly distributed on its outer periphery, these teeth 9 corresponding by pairs every twelve months of the year, and five teeth 10 out of its inner circumference, these teeth 10 each corresponding in the months of less than thirty-one days. Figures 2 to 4 show that the annual crown 8 is arranged eccentrically to the date ring 1. It is also arranged in such a way that it is operated, at the end of the month with less than thirty-one days, by a second finger 11 presented by the mobile calendar coach 6, this second finger 11 acting on one of the five inner teeth 10 of the crown 8. In the particular case shown in figure 3, the second finger 11 has just come into contact with tooth 10a of the crown 8 and will advance by one step (one twenty-fourth of turn or 15 °) said crown from IV to V as this is shown in figure 4. As you can see on the section of FIG. 5, the second finger 11 of the mobile 6 is an outgrowth of a disk 26 forced on the shaft 23, the disc 26 surmounting the disc 22 already described and being separated from the latter by a spacer 27. The section of the Figure 5 shows that the second finger 11 of the moving coach 6 is on the path of tooth 10a belonging to the annual crown 8. Note, however that finger 11 could be carried by the same disc 22 than finger 7, so items 26 and 27 could be deleted.

Figures 2 to 4 finally show that means meshing 12, 13 integral with the date ring 1 are used to engage or mate, at the end of each month, said date ring 1 and said annual crown 8 by one of its twenty-four teeth exterior 9.

The aforementioned means of engagement could consist of a single pin planted on the periphery of the date ring 1, or a cut and folded part from the edge of this ring, this folded pin or part engaging in twelve slots arranged on the periphery of the annual crown, these slots being separated by solid parts acting as teeth. We preferred however the use of two pins or lugs 12 and 13 planted perpendicularly on the periphery of the ring 1 by arranging so that the length circumferential X (see Figure 2) occupied by the two pins is substantially equal to the empty space Y separating two successive external teeth 9a and 9b that presents the annual crown 8. In any case, the respective diameters of ring 1 and crown 8 are chosen so that with each change of month, the crown 8 be driven by twenty-fourths of a turn (30 °) by the date ring 1. Similarly, the diameter inside the crown 8 will be chosen so that the teeth interior 10 cooperate with the second finger 11 in also allowing the cooperation of the first finger 7 with the teeth 2 of the date ring 1.

Figures 2 to 5 also show that the crown annual 8 pivots around a fixed guide disc 16 on plate 17 by means of two screws 28 and 29 (see Figures 2 to 4). These same figures also show that a first long necklace 18 rests between two successive teeth 2 of the date ring 1 and that a second jumper 19 rests between two successive outer teeth 9 of the annual crown 8. These necklaces allow angularly position the ring 1 and the crown 8 at the stop. Crown 8 is the reason why crown 8 has twenty-four external teeth 9, to define its twenty-four successive positions, while twelve teeth would be enough to cooperate with pegs 12 and 13. Finally, note that on the annual crown 8 twenty-four indications 14 are affixed, chosen here in Roman numerals, arranged in pairs and identifying the months of the year, these indications appearing through a window 15 pierced in the dial 5 as is shown in Figure 1. In the figures, the date appears at 3 a.m. and the month at 9 a.m. This display could appear in other places, for example the date at 12 o'clock and the month also at 12 o'clock but below.

Figure 2 also shows that it is possible to provide a quick corrector of 40 months which presents preferably two teeth attacking the outer teeth 9 of the annual crown 8, to make it move back two steps per turn of corrector 40. In a position taken from the control crown 61, the rotation thereof in a first direction activates the corrector 40, and in the other sense it activates the corrector 20. Such mechanisms of correction are well known in principle and have no need to be described here.

Alternatively, the guide disc 16 can be replaced by a fixed guide ring 32 (including one fragment is shown in broken lines in the figure 2) which surrounds and guides the periphery of the crown annual 8, for example by partially covering the teeth 9. This variant makes it possible to replace the screws 28 and 29, located inside the watch movement, by screws or other fasteners on the periphery of this movement and the date mechanism. This facilitates the application of the mechanism according to the invention as a separate module that can be mounted without difficulty on different watch movements, having including different turntables.

Note that with the two forms of guidance described above, the annular and eccentric annual crown 8 may be large enough to extend around the axis of rotation 33 (fig. 5) of the date ring 1, therefore also around the central trees 34, 35 and 36 bearing the seconds, minutes and hours hands in one classic timepiece, as shown by drawings. This results in multiple possibilities of combine different relative positions of windows 4 and 15 where the calendar and the month appear respectively. In addition, the crown 8 can be wide enough to wear the names of the months in whole or in abbreviation. Finger 11 can be on a radius smaller than that of finger 10.

Another possibility to indicate the month is to affix an index to the annual crown 8, for example colored, which is visible through a circular slit discontinuous or a circular row of openings in the dial above the crown, the names or month numbers are then inscribed on the dial. This display device which can be off-center on the dial offers interesting decorative possibilities and aesthetic.

The various elements constituting the invention having been defined above as well as their interactivity it remains to explain the functioning of the mechanism of annual calendar. Two cases may arise depending on whether it's months less than thirty-one days or thirty-one month.

The passage from the 30 to the first day of the following month in the case of a month of less than thirty-one days is illustrated in Figures 2, 3 and 4. In Figure 2, we have shown the mechanism as it stands on April 30 (month of thirty days) when its hour hand 70 and minutes 71 indicates 23 hours 45 minutes. At this moment the date displayed is 30 and the month displayed is the first indication IV (April). Pins 12 and 13 of the ring 1 are almost engaged between teeth 9a and 9b of the crown 8. Likewise the first finger 7 of the mobile driver 6 comes into contact with tooth 2a of the ring 1. In Figure 3, we see the same mechanism when the 70 and 71 minute hands indicate 0 hours 15 minutes on May 1. The first finger 7 of the mobile 6 has driven one step, by tooth 2a, the date ring 1 which then displays the date 31 (temporarily). The crown 8 has been advanced one step by the pin 12 acting on tooth 9b, this crown displaying the second IV (temporarily). The second finger 11 of the mobile 6 enters contact with tooth 10a of crown 8. In FIG. 4, sees the same mechanism when the hour hands 70 and 71 minutes indicate 4 hours 0 minutes on May 1st. The crown 8 has been driven a step by the second finger 11 of mobile 6 and now displays the first indication V (May). This same crown, of led that it is normally by ring 1, has become leading under the action of the finger 11 and then causes, by its tooth 9a, the date ring 1 by the pin 13. The ring 1 displays, at the end of the race, the number 1. Once this phase completed, pins 12 and 13 are disengaged teeth 9a and 9b and the ring 1 can continue its rotation day after day. In order not to mislead the wearer of the watch, we could replace the second indication of the months of less than thirty-one days (i.e. II, IV, VI, IX and XI) with a colored dot or a empty space.

The transition from 31 to the 1st of the following month in the case of a month of thirty-one days is not illustrated on the figures. It will be understood that in this case none of the five teeth 10 of the annual crown 8 is only found on the path of the second finger 11 of the driving mobile 6. By example, the annual crown 8 displays the month of May, or the first digit V as illustrated in Figure 4. A midnight, May 30, the date ring jumps to 31 (under the effect of the first finger 7) and advances by one step the crown 8 which then displays the second V (under the effect of the pin 12). At midnight on May 31, the ring of date jumps on June 1 under the effect of the finger 7 and further advances crown 8 which displays then the first VI (June) under the effect of the pin 12.

FIG. 6 is a partial repetition of FIG. 2. It shows the entire annual crown 8 and partially the date ring 1 as well as the mobile calendar coach 6. We can see that the teeth interior 10 of the crown 8 are arranged around the inner circumference of said crown successively at 60 °, 60 °, 90 °, 60 ° and 90 °. If these teeth 10, which represent the months of February, April, June, September and November are on the way to the second finger 11 mobile 6, the date will pass at the end of these months quickly from 30 to 31, then from 31 to 1st of the following month, as explained above.

If the system which has just been described continues the same purpose as that set out in document CH 684 815 previously cited, it presents, with respect to this precedence of notable simplifications by the number of reduced parts that it implements and by the bulk minimal it offers. Indeed the only new parts important are the annual crown 8 and a second finger 11. This system therefore sees the part only thicken by the thickness of this crowned. In addition, conventional movements with a single date ring are very easily adaptable to this new calendar.

Claims (11)

1. Annual calendar mechanism for a timepiece, said mechanism comprising a date ring (1) fitted with thirty one internal teeth (2) inside the ring, onto which are applied thirty one numbers (3) each corresponding to a day of the month which appear successively through a window (4) made in a dial (5), and a calendar driving wheel set (6) making one rotation in twenty four hours, said wheel set having a first finger (7) capable of driving the date ring (1) through one step once a day via one of its internal teeth (2), said wheel set controlling the date display, characterized in that the mechanism further comprises an annual ring (8) partially superposed on the date ring (1), making one rotation in a year and fitted with external teeth (9) in positions corresponding to the twelve months of the year and five internal teeth (10) in positions corresponding to the months of less than thirty one days, said annual ring (8) being arranged off-centre with regard to the date ring (1) and next to the calendar driving wheel set (6) so that it is actuated, at the end of months of less than thirty one days, by a second finger (11) of the calendar driving wheel set (6), this second finger (11) acting on one of the five internal teeth (10) of the annual ring (8), engaging means (12, 13) fixed to the date ring (1) being used to engage, at the end of each month, said date ring (1) with said annual ring (8) via at least one of said external teeth (9).
2. Mechanism according to claim 1, characterized in that the engaging means fixed to the date ring (1) consist of two pins or catches (12, 13) mounted perpendicularly on the periphery of the ring (1), a circumferential length (X) taken by the two pins being arranged so that said pins can engage, at the end of each month, in an empty space (Y) separating two successive external teeth (9a, 9b) of the annual ring (8).
3. Mechanism according to claim 1, characterized in that indications (14) identifying the months of the year are applied onto the annual ring (8), these indications appearing successively through a second window (15) made in the dial (5).
4. Mechanism according to one of the preceding claims, characterized in that the external teeth (9) of the annual ring (8) are twenty four in number and cooperate with a jumper spring (19) defining twenty four angular positions of the annual ring.
5. Mechanism according to claims 3 and 4, characterized in that at least those of said indications (14) which identify the months of thirty one days are applied twice onto the annual ring (8), to appear in the window (15) in two successive positions of said ring.
6. Mechanism according to claim 1, characterized in that the annual ring (8) is mounted around a fixed guide disc (16).
7. Mechanism according to claim 1, characterized in that the annual ring (8) is mounted inside a fixed guide ring (32).
8. Mechanism according to one of the preceding claims, characterized in that the annual ring (8) extends off-centre about an axis of rotation (33) of the date ring (1).
9. Mechanism according to claim 1, characterized in that it comprises a rapid date corrector (20), engaged with the internal teeth (2) of the date ring (1), said corrector being actuated by a control crown (61) of the timepiece.
10. Mechanism according to claim 9, characterized in that it comprises a rapid month corrector (40), engaged with the external teeth (9) of the annual ring (8), said corrector being actuated by the control crown (61).
11. Mechanism according to claim 1, characterized in that the five internal teeth (10) of the annual ring (8) are arranged around the inside of said annual ring at successive angular intervals of 60°, 60°, 90°, 60° and 90°.

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