WO2007048487A2

WO2007048487A2 - Digital display timepiece

Info

Publication number: WO2007048487A2
Application number: PCT/EP2006/009594
Authority: WO
Inventors: Marco Rochat
Original assignee: Frederic Piguet S.A.
Priority date: 2005-10-28
Filing date: 2006-10-04
Publication date: 2007-05-03
Also published as: EP1943564B1; WO2007048487A3; EP1780613A1; EP1943564A2

Abstract

A timepiece comprises a mechanical or electromechanical movement and is provided with a digital display (204, 316, 416, 530) consisting of four drums which are cinematically connected to each other, wherein the first drum (204) displays minutes by means of a scale (0-1-2-3-4-5-6-7-8-9), the second drum (316) displays tens of minutes by means of a scale (0-1-2-3-4-5), the third drum (416) displays hours by means of a scale graduation (0-1-2-3-4-5- 6-7-8-9) and the fourth drum (530) displays tens of hours by means of a scale (0-1-2), thereby enabling the four drums (204, 316, 416, 530) to provide a current time digital display around-the-clock. Said invention is characterised in that the third drum (416) comprises first means interacting with second means carried by the fourth drum (530) in such a way that said third drum (416) is enabled to move forward to one division per hour in normal time, i.e. between 00h00 and 23h59 and to pass from the division '3' to the division '0' when the display passes from 23h59 to 00h00.

Description

DIGITAL DISPLAY WATCH PIECE

The present invention relates to a timepiece such as a wristwatch. More specifically, the invention relates to such a timepiece capable of displaying the hours and minutes by means of four drums kinematically linked to each other, the first of which indicates the units of the minutes, the second the tens of minutes, the third the units of hours and the fourth the tens of hours. This gives a digital display twenty-four hours of the current time.

Timepieces with a digital display of the time of the aforementioned kind are already known from the prior art. A first category of these timepieces includes only three drums, namely a drum for minute units, a drum for tens of minutes and a drum for hours. In a first variant, the drum for the hours comprises the markings of "0" to "23" to allow the display of the twenty-four hours of a day. Such a solution, if it is possible for a timepiece of the table clock type, is hardly applicable in the case of a wristwatch. It is necessary to postpone on the perimeter of the drum twenty-four markings whose dimensions must be large enough that they can be read without difficulty. It requires a large diameter drum that can not be integrated in a wristwatch whose dimensions are necessarily small. According to a second variant, the drum for the hours comprises the markings from "0" to "12" to allow an hour display of the "meridium" type "AM", post meridium "PM". In this case, the drum has only thirteen markings and can therefore be expected smaller. However, not everyone is accustomed to a display of the English type "AM", "PM" and some people may have difficulty reading the time. A second category of digital timepieces includes four drums, namely a drum for minute units, a drum for tens of minutes, a drum for hour units and a drum for tens of hours. Such timepieces can display the twenty-four hours of a day by means of drums of smaller dimensions having at most ten markings of "0" to "9". However, these are timepieces such as electric clocks, each drum is driven individually by a motor. It is therefore difficult to integrate such an electric mechanism in a timepiece of the wristwatch type. Finally, Swiss Patent No. CH 150975 discloses the German utility model DE 73 28 799 and the Japanese utility model JP 55/010948 shows watches or pendulums comprising four drums or bands kinematically connected for the display of the hour in twenty-four hours. However, these documents are silent as to the delicate problem of changing the display from 23:59 to 00:00. Indeed, during the passage from 9:59 to 10:00, the drum units hours normally passes "9" to "0" and the drum tens of hours goes from "0" to "1". It is the same during the passage from 19:59 to 20:00, the drum unit hours normally passing from "9" to "0" while the drum tens of hours goes from "1" to "2". On the other hand, the passage of the display from 23:59 to 00:00 is much more difficult to manage. Indeed, the drum tens of hours must go from "2" to "0" while the drum unit hours must go from "3" to "0" and not "4" as such should be normally the case.

The present invention aims to overcome the aforementioned drawbacks as well as others by providing a timepiece with digital display comprising four drums in which a solution is provided to the passage of the digital display 23:59 to 0OhOO.

For this purpose, the present invention relates to a timepiece comprising a mechanical or electromechanical movement and provided with a digital display with four drums kinematically linked to each other, the first of these drums indicating the minute units by means of a graduation (0-1-2-3-4-5-6-7-8-9), the second indicating the tens of minutes by means of a graduation (0-1-2-3-4-5), the third indicating the hours units by means of a graduation (0-1-2-3-4-5-6-7-8- 9) and the fourth indicating the tens of hours by means of at least one graduation (0-1-2), the four drums thus providing a digital display of the current time over twenty-four hours, characterized in that the third drum comprises first means which cooperate with second means carried by the fourth drum to allow the third drum to advance one tick per hour in normal time and to move from the graduation "3" to the graduation "0" during passage of the display from 23:59 to 24:00.

Thanks to these features, the present invention provides a timepiece with digital display by means of drums capable of displaying the time over twenty-four hours and manage the passage of the display from 23:59 to 00:00. In addition, because of its compactness, the digital display mechanism with drums according to the invention can be integrated in any type of timepiece and, in particular, in a wristwatch. The present invention thus provides a wristwatch whose digital nature and purely mechanical display of the current time presents a original character that is distinctly different from conventional time displays by means of needles.

According to a complementary feature of the invention, the first means comprise a differential mechanism with two inputs, a first input being constituted by the movement of the watch, and the second input being constituted by the second means carried by the fourth drum.

According to another characteristic of the invention, the second means comprise a gear train which releases the second input of the differential only when the display changes from 23:59 to 00:00. Other features and advantages of the present invention will emerge more clearly from the detailed description which follows of an exemplary embodiment of the timepiece according to the invention, this example being given for purely illustrative and nonlimiting purposes only in connection with the attached drawing in which:

- Figure 1A is a sectional view of the left part of the digital display mechanism of the drum hour on which are notably visible the drums of hours units and tens of hours;

- Figure 1 B is a sectional view of the right part of the digital display mechanism of the drum hour on which are notably visible the finishing gear of the watch movement, the drum units of minutes and the drum tens of minutes, and

- Figure 2 is an enlarged view of the area surrounded by a circle in Figure 1 A on which we see the differential mechanism and the limiting device.

The present invention proceeds from the general inventive idea of providing a timepiece comprising a four-drum digital time display in which a compact solution allowing its arrangement in a wristwatch is brought to the passage of the watch. digital display from 23h59 to 0OhOO.

Designated as a whole by the general numerical reference 1, the four-drum digital time display mechanism is shown in section in its entirety in FIGS. 1A and 1B. This digital display mechanism 1 comprises for the a finishing gear train 100, a drum display mechanism 200 of the minute units, a drum display mechanism 300 of tens of minutes, a drum display mechanism 400 of the hour units, and a timing mechanism. drum display 500 tens of hours.

The finishing gear train 100 comprises a cylinder 102 which drives a medium-sized wheelchair 104 itself engaged with an average wheel 106 consisting of a medium gear 108 and an additional average gear 110. The average gear wheel additional 110 meshes with an intermediate mobile 112 comprising a driven return 114 and a drive gear 116. The drive gear 116 drives, via an input pinion 118, an axis of the minute units 202 which carries a drum of the minute units 204. This drum 204 indicates the units of minutes by means of a graduation (0-1-2-3-4-5-6-7-8-9) printed or engraved on its perimeter and moves continuously at the speed of a turn in ten minutes in front of a counter for minute units (not shown). An output wheel 206, fixed on the axis of the minute units 202, meshes with a second mobile 208 via an intermediate mobile 210 consisting of a pinion 212 and a wheel 214. The system is completed by standard elements such as an escape wheel, an anchor and an oscillator (not shown).

The minute unit axis 202 carries a tens of minute trainer 302 having two cut teeth 304 out of a total of twenty teeth and a tens minute limit disk 306 having a notch 308 indexed to the spacing between the two. 304 carved teeth of the trainer tens of minutes 302.

During the rotation of the minute unit drum 204 between the minutes "0" to "9", the tens of minute trainer 302 and the tens minute minute disk 306 rotate, driven by the unit axis of the units. minutes 202 on which is fixed the drum unit minutes 204. During this movement, the limiting disc tens of minutes 306 maintains in position an intermediate gear 308, a tooth 310 on two is truncated on part of its height . During the passage of the drum units 204 minutes "9" to "0", the trainer tens of minutes 302 drives via its two teeth 304 the intermediate gear 308 in the space of about a minute. In turn, the intermediate gear 308 drives with a pitch a pinion of tens of minutes 312 fixed on an axis of tens of minutes 314 which also carries a drum tens of minutes 316. This drum 316 indicates the tens of minutes by means of a graduation (0-1-2-3-4-5) printed or engraved on its perimeter and which passes in front of a desk for tens of minutes (not shown). The axis tens of minutes 314 carries the drum tens of minutes

316 which performs a complete turn in sixty minutes. It also carries a 402 hour unit trainer having two cut teeth 404 out of a total of twelve teeth and a 406 hours unit limiting disk having a notch 408 indexed to the spacing between the two cut teeth 404 of the coach of 402 hours units.

During rotation of the drum tens of minutes 316 between the minutes "0" to "59", the trainer of the hours units 402 and the disk of limitation of the units 406 hours rotate, driven by the axis of tens of minutes 314 on which is fixed the drum tens of minutes 316. During this movement, the limitation disk hours units 406 maintains in position an intermediate gear 409 of which one tooth 410 out of two is truncated on part of its height. When the drum passes tens of minutes 316 from the fifty-ninth to the sixtieth minute, the driver of the hours units 402 drives via its two teeth 404 the intermediate gear 409 in the space of about a minute. In turn, the intermediate gear 409 drives a pinion of the hour units 412 fixed on an axis of the hour units 414 which also carries a drum of the hour units 416 by one step. This drum 416 indicates the units of hours. hours by means of a graduation (0-1-2-3- 4-5-6-7-8-9) printed or engraved on its perimeter and which passes in front of a counter of hours units (not shown) .

A first input gear 502 of a differential mechanism 504 advances one step at the same time as the axis of the hour units 414 to which it is attached. As a second input gear 506 of the differential mechanism 504 is stationary as described in detail below, the reason for the differential mechanism 504 is -1 between the first input gear 502 and the drum of the 416 hour units. It is therefore important to insert a reversal switch 508 of the direction of the differential 504 between the first input gear 502 and a satellite wheel 510 to find the right direction of rotation of the drum of the hour units 416 and the advance of a not the latter.

The principle of driving the drum tens of hours 512 is the same as for other drums. The axis of the hour units 414 carries the drum of the hour units 416 which performs a complete revolution in twelve hours. It also carries a trainer of dozens of hours 514 comprising two truncated teeth 516 on a number of twenty teeth and a limit disk tens of hours 518 having a notch 520 indexed on the spacing between the two teeth 516 of the coach dozens of hours 514.

During the drum rotation of the hour units 416 between 0OhOO and 09:59, 10:00 and 19:59 and after 20,000, the trainer tens of hours 514 and the limiting disk dozens of hours 518 turn, driven by the axis 414. During this movement, the limiting disk tens of hours 518 maintains in position an intermediate gear 522 of which one tooth 524 out of two is truncated over part of its height. During the passages of the ^9th to the io ^th time and ig ^th to 20 hours ^èmβ coach dozens of hours 514 leads via its two teeth 516 on idler gear 522 in the course of about a minute. In turn, the intermediate gear 522 drives with a pitch a pinion of hours 526 fixed on an axis of tens of hours 528 which also carries a drum of tens of hours 530. This drum 530 indicates the tens of hours by means of a graduation (0-1-2) or preferentially (0-1-2-0-1-2) printed or engraved on its periphery and which passes in front of a window dozens of hours (not shown).

As already mentioned above, the digital display mechanism of time 1 according to the invention comprises a differential mechanism 504 whose first input is constituted by pinion 502 fixed on the axis of hours units 414, otherwise said by the movement of the watch, and whose second input is constituted by the pinion 506 which is released only during the passage of 23:59 to 0OhOO as will be seen below. Thus, in the operating mode of the watch, that is to say except during the passage of the display from 23:59 to 00:00, the axis of the hour units 414 rotates, causing the first input gear to rotate 502. In turn, the first input gear 502 drives, via the reversing gear 508, the satellite wheel 510 which is secured to a planet pinion 532 which itself meshes with a toothing 534 of the pinion 506 immobile. As a result, the planet pinion 532 rolls on the toothing 534 of the pinion 506, driving the drum of the hour units 416 in rotation.

Now let's take a look at the problem of changing the display from 23:59 to 00:00. Indeed, during the passage from 09:59 to 10:00, the drum unit hours 416 normally changes from "9" to "0" and the drum tens of hours 530 goes from "0" to "1". It is the same during the passage from 19:59 to 20:00, the drum unit hours 416 normally passing from "9" to "0" while the drum unit hours 530 changes from "1" to "2" . On the other hand, the transition from the display from 23:59 to 00:00 is much more difficult to manage. Indeed, the drum tens of hours 530 must go from "2" to "0" while the drum unit hours 416 must go from "3" to "0" and not "4" as such should normally be the case. For this purpose, in order to remedy the aforementioned problem, a third stage is provided on the axis of the hour units 414 as well as on the pinion of the tens of hours 526. On the axis of the hour units 414, a trainer Midnight 536 has been added. This trainer 536 has two cut teeth 538 on a number of twenty teeth, these two teeth being shifted by 144 ° with respect to the teeth 516 of the trainer for tens of hours 514. In fact, 144 ° = 4 ^* 36 °, the angle between the hours units "9" and "3". The intermediate gear 522 also has a specific cut opposite the trainer for tens of hours 514. In fact, only two teeth 540 on twelve teeth are cut on a part of the height of the intermediate gear 522. Thus, during the passage of the current hour from one hour to the next hour, for example from 13:00 to 14:00, nothing happens, the two teeth 540 of the intermediate gear 522 not lying next to the teeth 538 of the coach of midnight 536. On the other hand, during the passage from 7:00 pm to 2:00 pm, the tens of hours 514 brings the teeth 540 of the intermediate gear 522 opposite the teeth 538 of the trainer of midnight 536. Three hours later, during the passage of the 23 ^èmβ to the 24 ^th hour, the coach of midnight 536 drives one step the drum dozens of hours 530 via the intermediate gear 522 which drives the pinion tens of hours 526 fixed on the axis tens of hours 528. For this purpose, the disk limiting tens of 518 hours has a second notch 542 indexed on the spacing between the two teeth 538 of the midnight trainer 536. The indication of the drum tens of hours and passes from 23h59 to OxhOO.

At this precise moment, the digital time display mechanism displays an erroneous indication insofar as, if the drum of the tens of hours 512 indicates "0", the drum of the hour units 416 indicates meanwhile "4" because he has been trained only one step. It is therefore necessary to bring the drum unit hours 416 to the position where it indicates "0" is, in this case, to advance six steps, which corresponds to an angular displacement of 216 ° during which the indication of the units of the hour passes successively from the indication "4" to the indication "5" then "6" and until "0" is reached.

During the passage of dozens of hours from "2" to "0", the drum tens of hours 530 rotates 60 °, bringing with it the axis of the tens of hours 528. We take advantage of this movement of rotation to advance the drum unit hours 416. For this purpose, there is provided a corrective reference 544 units of hours with seven teeth cut 546 on a number of forty-nine teeth and whose teeth are indexed between the indications "2" and "0" of the drum dozens of hours 530. This correcting correction of the hours units 544 carries a limiting disk 548 of the intermediate gear 550 which has a notch 552 indexed on the teeth of the corrector unit 544. Outside the passage of dozens of hours from "2" to "0", the limitation disk 548 positions the intermediate gear 550 having fourteen teeth 554, two of which, opposite, are truncated over part of their height. A corrector 556 associated with the intermediate gear 550 and disposed on the same axis as it has eighteen teeth. During the passage at midnight, dozens of hours from "2" to "0", the seven teeth of the corrector 544 drive the intermediate gear 550 a half turn (seven teeth out of fourteen). The corrector 556 also turns a half turn (nine teeth on eighteen). It drives the same number of teeth an input drive gear 560 of the differential mechanism 504 having thirty teeth of 360 ^* 9/30 = 108 ° and the second input gear 506 of said differential 504. The reason for the differential 504 is 2 between the second input gear 506 and the drum of the hour units 416 via the planet pinion 532. The hour unit drum 416 is so turn 108 * 2 = 216 ° which corresponds to six steps, so that the display goes from "4" to "0".

It goes without saying that the present invention is not limited to the embodiment which has just been described and that various modifications and simple variants can be envisaged by those skilled in the art without departing from the scope of the invention as defined by the appended claims. In particular, the number of wheels, gears and references and their teeth can be changed. Similarly, it may be provided to add jumper springs to index the drums so as to ensure a fixed positioning of the markings in the windows. Note that indexing the drum unit hours by means of a differential allows a time setting clockwise or anti-clockwise. Finally, it should also be noted that all the display changes are made during the passage of the minutes unit from "9" to "0".

Claims

1. A timepiece comprising a mechanical or electromechanical movement and having a four-drum digital display (204, 316, 416, 530) kinematically linked to one another, the first (204) of these drums indicating the units of the minutes at by means of a graduation (0-1-2-3-4-5-6-7-8-9), the second (316) indicating the tens of minutes by means of a graduation (0-1-2- 3-4-5), the third (416) indicating the hours units by means of a graduation (0-1-2-3-4-5- 6-7-8-9) and the fourth (530) ) indicating the tens of hours by means of at least one graduation (0-1-2), the four drums (204, 316, 416, 530) thus providing a digital display of the current time over twenty-four hours characterized in that the third drum (416) has first means cooperating with second means carried by the fourth drum (530) to allow the third drum (416) to advance one tick per hour in normal time, that is, between 0OhO O and 23:59, and go from the graduation "3" to the graduation "0" when changing the display from 23:59 to 0OhOO.

2. Timepiece according to claim 1, characterized in that the first means comprise a differential mechanism (504) with two inputs, a first input being constituted by the movement of the watch, and the second input being constituted by the second means carried by the fourth drum (530).

Timepiece according to claim 2, characterized in that the first input of the differential mechanism (504) comprises a pinion (502) fixed on an axis of the hour units (414) which carries the drum of the units of hours (416), this pinion (502) meshing with a satellite wheel (510) via an inverting gear (508).

4. Timepiece according to any one of claims 2 to 3, characterized in that the second means comprise a pinion (506) which releases the second input of the differential (504) that during the passage of the display of 23h59 to 0OhOO.

5. Timepiece according to any one of claims 3 or 4, characterized in that the satellite wheel (510) is integral with a pinion (532) which itself meshes with a toothing (534) sprocket (506).

6. Timepiece according to any one of claims 3 to 5, characterized in that the axis of the hour units (414) carries a trainer tens of hours (514) having two truncated teeth (516). over a number of twenty teeth, the driver (514) driving at passages of 9 to 10 ^èmβ ^èmΘ hour and the 19 ^th to the 20 ^th hour, an intermediate pinion (522) which in turn causes a pinion tens of hours (526) fixed on an axis tens of hours (528) which carries the drum tens of hours (530).

7. Timepiece according to claim 6, characterized in that a midnight driver (536) carried by the axis of the hour units (414) has two cut teeth (538) on a number of twenty teeth, these two teeth being offset by 144 ° relative to the teeth (516) of the trainer for tens of hours (514), only two teeth (540) out of a total of twelve of the intermediate gear (522) being truncated on a part of their height so that, during the passage from 19:00 to 20:00, the trainer tens of hours (514) brings the teeth (540) of the intermediate gear (522) facing the teeth (538) of the coach of midnight (536) so that, when passing from the 23 ^th to the 24 ^th hour, midnight said driver (536) can drive through one step the drum dozens of hours (530) via the intermediate gear (522) .

8. Timepiece according to claim 7, characterized in that the drum tens of hours (530) is carried by an axis of tens of hours (528) on which is fixed a corrector (544) units of hours comprising seven cut teeth (546) out of a total of forty-nine teeth and whose toothing is indexed between the indications "2" and "0" of said hour drum (530), the corrective cross-section (544) causing a half-turn an intermediate gear (550) having fourteen teeth (554), two of which, opposite, are truncated over a portion of their height, a corrector (556) disposed on the same axis as the intermediate gear (550) in turn driving the second input gear (506) of the differential mechanism (504) via an input drive gear (560).

Timepiece according to any one of Claims 3 to 8, characterized in that the drum of the minute units (204) is carried by an axis of the minute units (202) on which a tens drive is fixed. of minutes (302) and a tens of minutes limiting disk (306) which step the drum by tens of minutes (316) when the drum of the minute units (204) of the indication "9 "to" 0 ".

10. Timepiece according to any one of claims 3 to 9, characterized in that the drum tens of minutes (316) is carried by an axis of tens of minutes (314) on which are fixed a trainer units hours (402) and an hour-limiting disc (406) which step the drum of the hour units (416) when the drum is moved for tens of minutes (316) from the indication "5 "to" 0 ".