EP0940833A1 - Calendar mechanism for watch movement - Google Patents

Abstract

The use of a 31-day wheel allows display of larger digits. The mechanism for indicating the date on a watch includes a tens indicator (8) having four positions. This comprises a cross shaped element having the digits 0 to 3 marked, or alternatively 1 to 3 with a blank limb. This makes one complete turn in ten days. The indicator for the units occupies a ring having thirty-one successive graduations marked 0 to 9 in three series. In addition there is a further 1 inserted between one of the zeros and its adjacent 1. This additional 1 provides for the 31st day in certain months.

Description

The present invention relates to a mechanism for calendar for watch movement and more particularly such a mechanism allowing the display large dates.

Wrist watches with a device date display with classic windows generally the disadvantage of being difficult to read due to the small size of the counters and the numbers transferred onto the indicator organs visible through these counters.

We already know from patent CH 342 270 a mechanism large date indicator for calendar watch including an intermediate wheel performing two rounds a day and all of whose teeth except one. The latter acts on a ring toothed with twenty teeth yes carries the unit numbers of the dates and mistletoe is visible through a large window. Each of these figures is repeated twice in succession on this ring. Thus any unit figure appeared at midnight in the counter is replaced at noon on the second revolution of the intermediate wheel, by a second digit identical which will not disappear until the next midnight for let appear the following unit figure. The ring further includes an additional tooth which, when passage from the second "zero" to the first "one" of the units, leads with a step a four-pointed star carrying the digits of tens of dates, i.e. digits "zero", "one", "two" and "three".

With this mechanism, however, it is necessary to act on the unit ring and on the tens star in end of the month to be able to move respectively from the twenty-eighth, twenty-ninth and thirty-first day of a end of month on the first day of the following month. This therefore requires the use of a correction mechanism complex which must allow in particular the displacement of the star of the tens of a step without displacement concomitant of the ring of units. Such mechanisms generally require the use of declutching the unit ring yes complicate the realization of these mechanisms and thus make them more expensive and larger.

The main object of the present invention is to remedy the drawbacks of the aforementioned prior art by providing a date display mechanism of large dimensions and therefore more readable, yes mechanism requires only extremely simple means and little manufacturing modifications of the basic movement in which it is integrated.

To this end, the invention relates to a mechanism for date for a watch movement comprising a member tens indicator with four positions bearing a graduation from "zero" to "three" or from "one" to "three" more a blank, designed to take at least one step every ten days, and a unit indicating unit planned for take one step every twenty-four hours, characterized by what the unit indicator can occupy thirty-one positions and carries three graduations from "zero" to "nine" successive, one of the three graduations having a "one" extra inserted between its "zero" and its "one".

Thanks to these characteristics, the date according to the invention allows, on the one hand, to display large calendars and, on the other hand, the change from the end of the month to thirty-one days on the first day of the following month without acting on a correction. In the case of a month of less than thirty-one days, the transition from the end of the month to the first day of following month is done using a mechanism of correction of classic dates.

According to an advantageous characteristic of the invention, the unit indicator body is associated with a first toothing with thirty-one teeth which cooperates with an organ coach, and a second toothing having four teeth of which three teeth drive the indicator organ of tens when crossing the "zero" of a graduation of the unit indicating unit at the "one" of the graduation next, while the fourth tooth drives the organ tens indicator when passing "one" additional from the graduation modified to the next "one".

According to a preferred embodiment, the organ unit indicator consists of an annular disc and the first and second teeth are teeth interior spaces that extend into two different planes.

• la figure 1 est une vue en plan d'une montre équipée d'un mécanisme de quantième selon l'invention;
• la figure 2 est une vue en plan du mécanisme de quantième selon l'invention;
• la figure 3 est une demi vue en plan dans laquelle l'organe indicateur des dizaines et l'organe indicateur des unités ont été partiellement arrachés, et
• la figure 4 est une vue en coupe partielle selon la ligne III-III de la figure 2 du mécanisme de quantième selon l'invention.

Other characteristics and advantages of the present invention will appear in the following description of a preferred embodiment, presented by way of nonlimiting example with reference to the appended drawings, in which:

• Figure 1 is a plan view of a watch equipped with a date mechanism according to the invention;
• Figure 2 is a plan view of the date mechanism according to the invention;
• FIG. 3 is a half plan view in which the tens indicator and the units indicator have been partially broken away, and
• Figure 4 is a partial sectional view along line III-III of Figure 2 of the date mechanism according to the invention.

The watch shown schematically in Figure 1 includes a date mechanism designated by the general numerical reference 1. The watch includes also other indicator mechanisms and organs. These will however not be described here since they are known to those skilled in the art and that they do not relate by directly the date mechanism according to the present invention.

We also see in Figure 1 that the watch equipped of the date mechanism 1 according to the invention comprises a dial 2 provided with two windows 4, 6 juxtaposed with six hours which in another form of execution could be brought together in one large window. Window 4 leaves appear a figure relating to the tens of a calendar, while the window 6 reveals a number relating to the units of a date so as to allow, according to their relative positions, the indication of digits from "one" to "thirty-one".

As can be seen in Figure 2, these numbers are carried by two different indicator members 8, 10, respectively the tens indicator body 8 and the unit indicating unit 10. The display of dates using these two organs 8, 10 thus allows to increase the respective dimensions of the figures worn by each of these bodies 8 and 10 and make the reading easier dates.

The tens indicator body 8 carries a graduation from "zero" to "three" or from "one" to "three" more one blank, and is scheduled to take one step every ten days. The indicator unit 10 has three successive graduations 10a, 10b, and 10c from "zero" to "new", the 10c graduation, known as modified graduation, having an additional "a" inserted between its "zero" and its "a". The indicator member 8 can occupy four positions different, while the indicator member 10 can occupy thirty-one different positions.

Referring to Figures 2 to 4, we see that the organ unit indicator 10 consists of an annular disc associated with a first internal toothing 12 comprising thirty-one teeth. A driving member 14 having the shape of a training finger and belonging to a basic movement M conventionally turns every twenty-four hours, training in a conventional manner the annular disc 10 by action on the teeth 12. A long necklace (not shown) secured to the basic movement M acts on the teeth 12 to hold the annular disc 10 in place when not driven. The organ unit indicator 10 is also associated with a second internal toothing 16 having four teeth 16a, 16b, 16c, and 16d. These teeth are distributed at the inner periphery of the annular disc 10 so that they drive the tens indicator body 8 during the respective passage of the "zero" of the graduations 10a, 10b and 10c from the indicator unit 10 to the "one" of the next graduation. The fourth tooth 16d drives the tens indicator body 8 when passing the "one" additional graduation modified 10c to "one" following this same graduation.

With particular reference to Figure 4, we see that the teeth 12 and 16 extend in two different planes, the teeth 16 cooperating with a star 18 with four teeth secured to the indicator member of the tens 8, star 18 being positioned by a jumper 20.

In the example illustrated, the indicator body of the tens 8 moves above the annular disc 10 and includes cutouts that reveal the number units carried by said annular disc 10 and in front be displayed through window 6. Preferably, the tens indicator 8 consists of a disc cut in the shape of a cross with four branches, the branches marked with the numbers "zero", "one", "two" respectively and "three" as shown, or "one", "two", "three" and a white.

The mechanism according to the invention further comprises a support plate 22 of the star 18, of the tens cross 8 and the annular disc of the units 10. This plate 22 is arranged on the surface of the basic movement M at which is associated with the date mechanism according to the invention. More specifically, the star 18 is rotatably mounted in a recess 24 made in the upper surface 26 of plate 22, the tens cross 8, integral with the star 18, extending in a second recess 28 also produced in surface 26 and located between this surface and the bottom of the recess 24. The plate 22 also includes, dug in its surface 26, a path annular 30 on which the indicator member of the units 10. This annular path 30 includes a recess 32 in which the internal teeth 12 extend to cooperate with the training finger 14.

We will now describe how the date mechanism according to the present invention. The drive finger 14 acts once every twenty-four hours on toothing 12 to advance the disc annular 10 of a thirty-first of a turn. So a digit of any unit of date appeared, by example, at midnight in window 6, will be replaced when passage at midnight following by the number which makes it after.

At the "ten", "twenty" and "thirty" of the month, the finger drive 14 acts on the teeth 12, as described above, to pass the "nine" of the graduation of units corresponding to "zero" of the following graduation, teeth 16a, 16b and 16c of teeth 16 acting on the star 18 to simultaneously pass the number of tens from "zero" to "one", from "one" to "two" and from "two" to "three" respectively.

Note in this regard that in the embodiment illustrated, the teeth 16a, 16b, and 16c are arranged respectively appreciably opposite the figures "eight" graduations 10a, 10b, 10c.

When changing from "thirty" to "thirty-one", the drive finger 14 acts normally on the teeth 12, as described above, and passes the "zero" of the graduation of units 10b at the first "one" of the graduation of units 10c, none of the teeth of toothing 16 not acting at this moment on the star 18, so that the cross 10 remains stationary and always displays the "three" of tens.

When switching from "thirty-one" a month to "one" of the month following the training finger 14 acts normally on toothing 12, as described above, and passes the first "one" of the unit scale 10c on the second "one" of this same graduation. Simultaneously, the tooth 16d of the toothing 16 acts on the star 18 to pass the number "three" carried by the tens cross 10 at "zero" or at a range white display.

It is thus understood that the date mechanism according to the invention is designed so that the cross 8 tens performs one revolution per month in four steps, the same tooth of the teeth 16 always producing the display of the same figure, while the annular disc makes a turn every thirty-one days.

In the case of a thirty-one day month, the change from the last day of this month to "one" of the following month can be performed using a correction device 34 with sliding pinion and rocker known per se which acts directly on the teeth 12 of the annular disc 10. The device 34 notably comprises a wheel 36 engaged with a sliding pinion 38 with three teeth. In a first sense of rotation of the correction rod 40 partially shown, the wheel 36 drives the pinion 38 guided in an oblong hole (not shown) for engaging with the teeth 12 of the annular disc 10. The latter is then moved clockwise by the number of steps required to bring up the second "one" of the graduation 10c in window 6. Conventionally, the pinion 38 is released from the teeth 12 when the rod 40 is actuated in the opposite direction of rotation to the first direction. It will be noted that the date mechanism according to the invention can, without major modification, use the correction of dates of a classic movement. The use of such a correction mechanism allows manually ensure the passage from the end of a month of less than thirty-one days on the first day of the month following easily and quickly.

Some changes can be made to the date mechanism which has just been described without as well go beyond the scope of this invention. So by example, we could consider moving the axis of rotation of the cross 8 from the tens towards the center of the movement M so that it no longer moves above the annular disc 10, but comes to move in juxtaposition of it. In this case, window 4 would of course be placed above window 6 on the axis 12 hours 6 hours.

Claims (8)

Date mechanism for movement timepiece (M) comprising a member indicating the tens (8) in four positions with a graduation of "zero" to "three" or from "one" to "three" plus a blank, expected to take a step every ten days, and an organ unit indicator (10) intended to take one step per day, characterized in that the unit indicating unit (10) can occupy thirty-one positions and wears three graduations from successive "zero" to "nine", one of these three graduations, called modified graduation, having a "one" extra inserted between its "zero" and its "one". Date mechanism according to claim 1, characterized in that the unit indicating member (10) is associated with a first toothing (12) at thirty-one teeth which cooperate with a driving member (14) and with a second toothing (16) comprising four teeth, three of which teeth drive the tens indicator (8) when of the passage from "zero" to a graduation of the organ indicator of the units (10) at the "one" of the graduation next, and whose fourth tooth drives the organ tens indicator (8) when passing "one" additional from the graduation modified to the next "one". Date mechanism according to claim 1, characterized in that the unit indicating member (10) consists of an annular disc and that the first and second teeth respectively (12) and (16) are internal teeth which extend in two planes different. Date mechanism according to claim 2, characterized in that the tens indicator (8) moves over the unit indicator (10) and includes cutouts revealing the number of units to be displayed. Date mechanism according to claim 4, characterized in that the unit indicating member (8) consists of a cross-cut disc associated with a four-pointed star (18) which cooperates with said second toothing. Date mechanism according to claim 5, characterized in that it comprises a plate (22) in which dozens disk (8) and star (18) are rotatably mounted, said plate (22) further comprising an annular path (30) on which the said movement moves unit disc (10). Date mechanism according to claim 6, characterized in that the annular path (30) comprises a recess (32) in which the first toothing extends interior (12) for cooperating with said driving member (14). Date mechanism according to claim 7, characterized in that the first toothing (12) extends below of the level of said second toothing (16).

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