Patent Grant
10928777
This application is a national phase of PCT/IB2017/051498, filed on Mar. 15, 2017, which claims the benefit of Swiss Application No. 00348/16, filed on Mar. 15, 2016. The entire contents of these applications are hereby incorporated by reference.
The present invention relates to a correction mechanism for a watch movement with retrograde and jumping display.
Retrograde displays, namely displays in which a hand or a disk rotates in one direction over a given period and then snaps back almost instantaneously to the initial position by rotating quickly in the opposite direction at the end of this period, are known in horology. These retrograde displays are used, for example, to indicate minutes over a graduation from 1 to 60 covering a circular arc of under 360°. These retrograde displays make it possible to free up space on the dial for indicating other information. Furthermore, the rapid return of the minutes indicator every hour creates movement on the watch face.
Jumping displays, in which a time indicator jumps almost instantaneously from one value to another, are also known. These jumping displays are notably used for displaying the date in a window. They are sometimes used to indicate other information, including indicating the current hour in a window. Within the present application, the expression “jumping display” covers both displays in which the jump is near instantaneous and displays referred to as trailing displays in which this jump is not as rapid, although the moving-on of the display is nevertheless discontinuous.
Watches that combine a retrograde display and a jumping display are also known.
CH691833 describes one example of a watch comprising a jumping hours display and a retrograde minutes display. A minutes rack has two toothed parts, one for transmitting the movement to the minutes display member and the other to be driven by a pinion with one missing tooth, this pinion being fixed to the hours wheel and driven at the rate of one revolution per hour. The instantaneous return of the rack corresponds to the movement of the last tooth of the rack at the site of the missing tooth of the pinion. This correction device exhibits the major disadvantage of increasing the bulk of the movement and of being complex.
EP0788036B1 relates to a watch with a retrograde minutes display and a jumping hours display on a disk. A lever is progressively lifted once per hour by the rotation of a snail cam secured to the minutes wheel.
It is an object of the present invention to create a simple correction mechanism for a watch movement, combining both a retrograde display and a jumping display.
It is an object of the present invention to propose a time correction mechanism for a watch movement with retrograde and jumping display, which is free of the limitations of the known time-setting mechanisms.
Another object is to propose a correction mechanism which allows more rapid and less restrictive correction of the current time.
According to the invention, these objects are notably achieved by means of a movement and of a method according to the features of the corresponding typical claims.
According to the invention, the watch movement comprises:
By virtue of the two-directional correction of the retrograde display, it is possible to correct its position without completing a full revolution. The time can thus be set more quickly.
For example, in the case of a retrograde minutes display, it is possible to correct the position of this indicator in both directions. If the watch movement gains by a few minutes, it can therefore be corrected back without having to make an almost full revolution forwards and without affecting the position of the hours indicator.
This solution thus offers the advantage over the prior art of allowing a simple and quick correction of the retrograde indicator, for example the minutes indicator.
The corrections of the retrograde indicator in the clockwise direction are transmitted to the jumping hours ring. In the case of a retrograde minutes indicator, this for example makes it possible to correct the jumping hours indicator in the clockwise direction, with a jump by one hour each time the minutes indicator moves on from 59 to 00. This correction of the jumping hours ring can be achieved very simply by using the jumping hour drive mechanism used during normal watch operation.
The corrections of the retrograde minutes indicator in the counterclockwise direction (in order to retard it) are, by contrast, preferably not transmitted to the jumping hours ring. This is because the usual jumping hours drive mechanisms do not usually allow a jump to be made in the counterclockwise direction; they are designed only to move the jumping hours ring on in the clockwise direction, under the action of the geartrain. In other words, the correction is not driven by the crown in the counterclockwise direction. For example, jumping hours drive mechanisms often comprise a cam with a jump, for example a snail cam, with a jump that can be crossed only in one direction. By avoiding transmitting the corrections in the counterclockwise direction to the jumping hours ring, the need to modify the drive mechanism of this ring is thus avoided.
By thus choosing a correction that is unlimited in the clockwise direction, but limited in terms of correcting the minutes in the counterclockwise direction, a movement is obtained that is practical, easy to manipulate, and at the same time considerably simplifies construction in relation to a movement that allows correction that is unlimited in both directions which affords merely a small improvement in convenience for a considerably greater complexity.
This construction thus makes it possible to produce a correction mechanism that is simple, allowing a great many corrections to be made with very few manipulations of the crown and without needing to modify the jumping hours ring drive mechanism.
In one embodiment, a correction blocking mechanism is provided to prevent the retrograde mobile from being corrected in the counterclockwise direction within a range around the jump of this mobile, and to allow same in all the other positions of this mobile outside of that range. For example, if the retrograde mobile displays minutes, the mechanism may prevent correction in the counterclockwise direction when the retrograde minutes indicator is indicating a value in a range including the minute 60. That makes it possible to avoid the risk of the jumping hours indicator accidentally moving on as a result of a correction in the counterclockwise direction to the minutes mobile in this range.
This correction blocking mechanism may be connected to the cam feeler, which may be on the rack, and block the rotation of a snail cam in one of the two directions of rotation when this snail cam is situated near to the position of the feeler jump.
In the movement according to the invention, the asymmetric internal toothing may comprise a plurality of teeth with asymmetric flanks, the drive member being arranged in such a way as to be able to butt against one flank of a tooth of the internal toothing and to be able to drive the hours ring when the retrograde mobile is rotating in one direction, and to be able to slide along another flank of a tooth of the internal toothing when the retrograde mobile is rotating in the opposite direction.
In one embodiment, the retrograde mobile may display the minutes.
The movement may comprise a snail cam and a feeler engaging with the snail cam in order to act on the rack to drive the retrograde mobile.
The feeler and the rack may be incorporated into a single component or may be made up of two separate components.
The movement according to the invention may comprise a spring mounted on the rack and able to apply a return force to the drive member in order to press it against the internal toothing of the hours ring.
In the movement according to the invention, the snail cam rotating in a first direction of rotation may drive the rack and the retrograde mobile in the opposite direction of rotation to the first direction.
The movement according to the invention is designed to allow unlimited correction of the hours and minutes display in the clockwise direction.
The movement according to the invention may be designed to allow correction of the hours in the clockwise direction, in a jumping way.
The movement according to the invention may be designed to allow correction of the minutes display in the counterclockwise direction.
The movement according to the invention may be designed to allow correction of the minutes display in the counterclockwise direction only when the minutes indicator is in a first range, and to prevent any correction of the minutes display in the counterclockwise direction when the minutes indicator is in a second range.
The movement according to the invention may comprise a correction blocking mechanism to prevent the minutes from being corrected in the counterclockwise direction within a range that includes the instant at which the retrograde mobile returns, and to allow the minutes to be corrected in the counterclockwise direction outside of that range.
That makes it possible to avoid the risk of the jumping hours indicator accidentally moving on as a result of a correction of the retrograde mobile close to the instant at which the mobile returns.
According to the invention, the method for correcting the display of an item of time-based information on a watch movement may comprise the following steps:
in a first interval, for example in an interval from 0 to 59 minutes:
This solution offers the advantage of a correction of the minutes in the range 0 to 59 min which does not interfere with the hours disk and can therefore be performed in both directions.
Preferably, the rotation of the drive member pressing against a second flank of the internal toothing of the ring drives this ring near-instantaneously.
The correction method according to the invention may exhibit steps in which:
This solution offers the advantage of allowing the retrograde minutes and the jumping hours to be adjusted with the time-setting stem in the same correction position.
This solution offers the advantage that the minutes can be adjusted in both directions, clockwise and counterclockwise.
In the correction method according to the invention, the correction of the minutes display in the counterclockwise direction may be limited to the 0-59 minutes interval.
Exemplary embodiments of the invention are indicated in the description which is illustrated by the attached figures in which:
The first end 31 of a rack 3 follows the rotation of a snail cam 5 borne by a driving release wheel 52. This driving release wheel 52 is driven by the wheel 7 of the geartrain in such a way that the minutes indicator 2 travels over the minutes scale 9 (
The correction mechanism is illustrated in
In position “P0” illustrated in
When the time-setting stem 10 is brought by the user into the position “P1” in the direction of the arrow A, the pull-out piece 11 is held in the indentation 121 of the pull-out-piece jumper 12, while at the same time driving the lever 13 and the sliding pinion 15 in the direction of the arrow B so that the sliding pinion 15 engages with the first correction transfer gear 16.
The first correction transfer gear 16 in its turn engages with the second correction transfer gear 18. With reference to
As illustrated in
The second end 32 of the rack 3 comprises an oblong opening equipped with an internal toothing 320. The rack 3 pivots about a pivot point 34 under the action of the snail cam. During this pivoting, the internal toothing 320 of the second end of the rack 32 engages with the external toothing 200 of the retrograde mobile 20 so that the retrograde indicator 2 borne by the retrograde mobile 20 turns in the same direction as the second end of the rack 32.
A rack end-stop 35, the purpose of which will be detailed later on, is connected to the rack 3 and makes it possible to prevent the snail cam 5 from rotating in the clockwise direction, at least in a blocking range when the feeler 31 is close to the jump of the cam.
The movement of the rack is transmitted to a drive member, here consisting of a tooth 4 articulated to the second end of the rack 32 by means of the axis 41. A return spring 42 applies a return force to the tooth 4 in order to press it against the toothing 610.
Hours indications 6 are borne by the hours ring 60. This ring is mounted on the smaller-diameter drive ring 61. In an alternative form which has not been illustrated, it is also conceivable for the hours indications 6 to be positioned directly on the drive ring 61 or on a ring of the same diameter.
The drive ring 61 comprises an internal toothing 610 with a plurality of teeth around the entire internal periphery. The spacing between the teeth is an even spacing. The teeth have two asymmetric flanks 6100 and 6101. The first flank 6100 is almost radial in relation to the diameter of the ring 61 and allows the ring 61 to be driven by means of the drive member (tooth) 4. The second flank 6101 is inclined and forms an angle of less than 30° with the tangent to the ring 61 so that when the tooth 4 is in contact with the second flank 6101, it can slide along this second flank 6101 without driving same, and without driving the ring 61 either.
The drive ring 61 further comprises an external toothing 611 exhibiting teeth 6110 the tips of which are concentric with the drive ring 61, the hollow 6111 between each of the teeth 6110 being designed to accept the end 620 of a positioning jumper 62. The jumper 62 thus collaborates with the external toothing 611 in order to center the hour indications 6 in a window (not depicted). The end 620 of this jumper 62 opposes the movement of the ring 61 by engaging in the hollow 6111 between the teeth 6110 of the external toothing of the drive ring 61. The stiffness of the jumper 62 is chosen such that it holds the hours drive ring 61 in place when said ring is not being driven by the tooth 4 and so as to allow the end of the jumper 620 to disengage from the hollow 6111 of the external toothing of the hours ring 611 under the action of the tooth 4 on the toothing 6100 and by virtue of a rack spring 33.
The operation of the correction mechanism during corrections in the clockwise direction, namely in order to move the indicated time forward, between minutes 0 and 60, will now be described with the aid of
When the time-setting stem 10, pulled axially into the correction position “P1”, turns in a first direction in order to move the displayed minute forwards, it drives the snail cam 5 in the counterclockwise direction, thus causing the first (feeler) end 31 of the rack 3, the second end of the rack 32, the retrograde indicator 2 and the tooth 4 to rotate in the clockwise direction with respect to the pivot point 34. Friction on the drive wheel 7 (
During the course of the interval illustrated in
Because the movements of the rack 3 in the counterclockwise direction have now to be transmitted to the hour ring 60, it is important to ensure that the minutes are not manually corrected backwards, as this would cause the rings 60 and 61 to move. It would then be possible to leave the hours disk 60 between two figures depending on the minute at which the correction was stopped.
In order to avoid this risk, as can be seen in particular in
The rack stop 35 acts only in a limited range when the feeler 31 is just before the fall of the cam; it remains possible to rotate the cam 5 in both directions outside of this range. In one embodiment, the rotation of the snail cam 5 is blocked in the clockwise direction when the minutes indicator is between 57 and 59 minutes.
At minute 60, the falling of the rack 3 onto the snail cam 5 simultaneously causes a near-instantaneous return of the minutes indicator 2 to 0 in the counterclockwise direction and a jump of the hours ring 61, likewise in the counterclockwise direction, so as to display the next hour. This return is illustrated in
The correction mechanism 1 thus allows jumping correction of the hours display in the clockwise direction. This correction is achieved through the intermediary of the minutes correction mechanism 1, by turning the time-setting stem 10 into the correction position “P1”. A correction of unlimited amplitude can thus be performed in the clockwise direction.
The operation of the correction mechanism in the counterclockwise direction between minutes 0 and 59, namely by turning the time-setting stem in a second direction in order to “turn back time”, will now be described. Rotating the time-setting stem in the second direction causes the snail cam 5 to rotate in the clockwise direction, and causes the rack 3, the retrograde minutes indicator 2 and the drive member 4 to rotate in a counterclockwise direction. In this direction, the correction movements of the windings stem are transmitted to the snail cam 5 and to the rack 3. Between minutes 0 and 59, the drive member 4 driven in the counterclockwise direction slides against the second flank 6101 of the drive ring 61, without moving same.
From minute 57 onwards, or as soon as the snail cam enters the rotation-blocking range, the rack stop 35 presses against the edge of the fall of the snail cam 5 and prevents the latter from continuing its rotation in the clockwise direction, as explained above. If the user forces the issue, the friction wheel 17 (
After the fall, namely at minute 0, rotation of the snail cam 5 in the clockwise direction is blocked by the rack 3 which cannot climb back up the fall of this snail cam 5. The friction wheel 17 slips and the movements of the time-setting stem remain ineffectual.
It is therefore not possible to move on directly from minute 01 to minute 59; the friction wheel 17 prevents this movement. However, the user can correct the time using a suitable number of rotations in the clockwise direction.
In the clockwise direction, this correction device thus allows an unlimited correction to be made to the hours and to the minutes with, between the end of minute 60 and minute 0, a near-instantaneous return of the minute hand 2 and a synchronized jump of the hours indicator 6.
In the counterclockwise direction (in order to turn back time), this correction device thus allows the minutes to be corrected only outside of the blockage range, for example between minute 57 (or 59) and minute 0.
As will be discussed later on, the return spring 44 and the jumper 64 which are illustrated in
It is important to emphasize at this point that it is not essential to have the return spring 44 and the jumper 64 both present at the same time. It is possible for example to envision a mechanism comprising the return spring 44 of
The return spring 44 of the alternative form of
In order to demonstrate the difference in shape between the jumper 62 of
If the jumper 62 of
By contrast, the jumper 64 of
The alternative form illustrated in
In the alternative form illustrated in
| Number | Date | Country | Kind |
|---|---|---|---|
| 0348/16 | Mar 2016 | CH | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2017/051498 | 3/15/2017 | WO | 00 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2017/158527 | 9/21/2017 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5784342 | Genta | Jul 1998 | A |
| 5943299 | Genta | Aug 1999 | A |
| 7969824 | Wiederrecht | Jun 2011 | B2 |
| 8004936 | Ruchonnet | Aug 2011 | B2 |
| 9239570 | Graemiger | Jan 2016 | B2 |
| 10222749 | Denden | Mar 2019 | B2 |
| Number | Date | Country |
|---|---|---|
| 691833 | Oct 2001 | CH |
| 203069969 | Jul 2013 | CN |
| 0788036 | Aug 1997 | EP |
| 1868048 | Dec 2007 | EP |
| Entry |
|---|
| International Search Report for PCT/IB2017/051498 dated Jul. 6, 2017, 2 pages. |
| International Written Opinion for PCT/IB2017/051498 dated Sep. 21, 2017, 6 pages. |
| Number | Date | Country | |
|---|---|---|---|
| 20190086867 A1 | Mar 2019 | US |
