HK1193882B - Mechanism for driving an indicator for a timepiece - Google Patents

Description

The present invention relates to a mechanism for driving an indicator for a watch part, e.g. the indicator is a quantum, day of week or month indicator in a calendar display, and may be in the form of a needle or disc.

In particular, the present invention relates to an indicator drive mechanism in which an indicator drive device, such as a solid star indicator, is actuated by a nozzle of a swing-controlled cam. Examples of such a mechanism are described in CH 702.137 (for an instantaneous meter) and EP 1.115.041 (for a rapid quantium corrector).

In this type of mechanism, the cam-controlled rocker performs a back and forth rotational movement that moves its beak in and out of the drive mobile's denture. When it releases from the drive mobile's denture the beak touches a tooth of the latter, which requires either making the beak retractable to avoid blockage, as in patent CH 702.137, or accepting that the release of the beak causes a momentary retraction of the traction mobile, as in patent EP 1.115.041, which is then caught up by the positioning jump of the drive mobile.

The first swing carries a clapper terminated by a clapper terminating the first swing and pins, which guide a first arm of a second swing to control the latter. When the first swing is gradually lifted by the clapper, the clapper's tip comes out of the clapper to touch the toothless wheel. Towards the end of this lift, a second, elastic arm of the second swing presses the clapper to make it rotate around its porthole by the first swing and bring the clapper into the clapper.When the first swing is made from the top to the bottom of the cam, the beak moves the cog by one step. Thus, in this mechanism, the beak of the clapper cyclically describes a closed curve whose shape allows the beak to exit the cog of the cog without touching it. This mechanism therefore does not have the disadvantages mentioned above in relation to documents CH 702.137 and EP 1.115.041.The clutch is no longer subject to the action of the elastic arm of the second swing and is therefore only held in the gear gear gear by the pull angle, determined by the shape of the beak and the gears of the gear. This leads to a risk of the beak disengaging from the gear gear gear gear, especially in the event of a shock. EP 0 606 576 describes a drive mechanism for a calendar with two swings (8, 40) each driven by a cam (5, 43).Each swing is in motion around a pivot (9, 41) and elastic means (12, 42) allow contact between the swingers and cams to be maintained.

The present invention is intended to remedy the above drawbacks and to this end proposes a mechanism for the actuation of an indicator for a watch part, including: a first swing mounted around a first pivot and comprising a nozzle designed to cooperate with a mobile's gear to move the mobile, a first swing mounted to rotate the first swing around the first pivot, a second swing mounted around a second swing and supported by the first swing, a second swing mounted to rotate the second swing around the second swing, and elastic means of maintaining cooperation between the swing and the cams, the swings and cams are arranged so that the tip of the first swings cyclically describes a closed curve, each cycle comprising a first movement during which the tip leaves the mobility gear without changing the angular position of the mobility gear and a second movement during which the tip enters the mobility gear to move the mobility gear.

The use of both cams and the second swing thus enables the first swing to exit the denture of the mobile without touching it and to enter the said denture by moving the mobile forward. The mouthpiece does not therefore need to be retractable; it can be rigidly linked with the rest of the first swing, which will in particular prevent the mobile from moving under the effect of its inertia just after it is actuated by the first swing in the event that the movement of the mobile is at instantaneous jumps. The elastic means can keep the beak in the beak of the mobile tooth with a sufficient force to block the movement of the tooth, after the elastic means of the retractable beaks of the tooth state must be sufficiently weak to allow retraction during the exit of the tooth.

Preferably, the first and second cams are coaxial.

The mechanism of the invention may also include a third swing mounted around a third pivot and arranged so that the first swing is driven by the first cam through this third swing.

A device may be provided to automatically remove the denture tip of the movable before correcting the position of the movable.

This device can be operated, for example, by moving a lift rod into a predetermined axial position.

This may include means of moving the second swing away from the second cam, this removal causing a displacement of the first swing and pushing the beak out of the mobile's denture.

The present invention also relates to a calendar mechanism including a mechanism as defined above.

The present invention finally concerns a watch part incorporating a mechanism as defined above.

Further features and advantages of the present invention will be apparent from the following detailed description made by reference to the attached drawings in which: Figure 1 shows a calendar mechanism according to a first embodiment of the invention; in this figure three pendulums are drawn with lines of different thicknesses and two cams are drawn with lines of different thicknesses to enable the reader to distinguish them better; Figure 2 shows a sequence of calendar mechanism states according to the first embodiment of the movement when the hour handles of the watch part rotate by a number of turns corresponding to 24 hours of rotational time in the direction of the clock; Figure 3 shows a sequence of calendar mechanism states according to the first embodiment of the movement when the hour handles of the watch part rotate by a number of hours of rotational time corresponding to 24 hours of rotational time; Figure 2 shows a sequence of time in a second embodiment of the mechanism when the watch part rotates by a number of hours of rotational time; Figure 9 shows a time-out display in a second embodiment of the movement; Figure 8 shows a correction of the number of turns corresponding to a number of hours of rotational time in the direction of the clock; Figure 9 shows a time-out display in a number of time-out indicators corresponding to 24 hours of rotational time; Figure 8 shows a time-out display in a time-out mechanism corresponding to a number of 6 hours of rotational time in the second embodiment of the watch part of the watch part rotating time; Figure 9 shows a time-out mechanism corresponding to a time-out mechanism corresponding to a number of time-out mechanism corresponding to a second embodiment of the second embodiment of the time-out mechanism.

For the purposes of this invention, calendar means, inter alia, the indication of the quantity and/or day of the week and/or month.

As shown in Figure 1, a calendar mechanism according to a first embodiment of the invention for a watch part such as a wristwatch consists of a calendar wheel 1 which is classically driven by the finishing gear of the watch part during normal operation of the watch part. The calendar wheel 1 thus rotates at a rate of one turn every 24 hours in the direction indicated by the arrow S1.

Two cams, namely a calendar cam 2 and an insulation cam 3, are coaxial to the calendar wheel 1. An eccentric pin 4 cast into the calendar cam 2 is engaged in a circle arc opening 5 of the calendar wheel 1 comprising a first end 6 and a second end 7. The pin 4 and the opening 5 define a rotation range of the calendar cam 2 relative to the calendar wheel 1. The insulation cam 3 is itself solidary to the calendar wheel 1. Each of the cams 2, 3 comprises a right armament radius 2a, 3a, crescent, a lower part between 2b, 3b and a 2c, a lower part between 2d, 3b, 2d and 3b. In its positive example, the positive part of the fall is defined by the fall between 2d and 3b.

A cam 8 swing mounted around a pivot 9 is applied part of the time against the calendar cam 2 by a spring 10. An insulation swing 11 mounted around a pivot 12 is applied against the insulation cam 3 by a spring 13. The pivots 9, 12 are mounted on a fixed part of the movement of the watchpiece, such as the turntable or a bridge. Contact between the cams 8, 11 and cams 2, 3 is preferably made via pebbles 14, 15 mounted respectively on the cams 8, 11 and which run on cams 2, 3.

A calendar swing or actuation swing 16 is mounted around a pivot 17 carried by the isolation swing 11 and has an oblong U 18 opening that receives a pin 19 carried by the cam swing 8. Thus, the calendar swing 16 is controlled by both the cam swing 8, thus by the calendar swing 2, and by the isolation swing 11, thus by the isolation swing 3. The calendar swing 16 has beaks 20, 21 that cooperate with a quantum star 22 and a day star 23 respectively. Indicators such as quantum hands or discs are solidary of the stars 22, 23 respectively and indicate to the user the day of the month and the day of the week in cooperation with the gradations or cadranes of a clockwork.

Figures 2 (a) to 2 (g) show different successive configurations of the calendar mechanism according to this first embodiment of the invention during normal operation of the watch movement or during forward timing, i.e. in the clockwise direction of the watch movement's hourly indicators, where the calendar wheel 1 and with it the insulation cam 3 rotate in the S1 direction.21 of the calendar swing 16 are in the star gear 22, 23 respectively, the cam swing 8 is out of contact with the cam swing 2 because held against the action of spring 10 by the calendar swing 16 which cooperates with the pin 19, the insulation swing 11 is applied against the lower part 3b of the insulation swing 3 and the pin 4 is away from the ends of the oblong opening 5, especially the first end 6. From this configuration, the cooperation between the armament part 3a of the insulation swing 3 and the insulation swing 11 causes the lifting of the insulation swing 11 against the action of the spring 13,The beaks 20, 21 of the calendar swing 16 thus begin to emerge from the teeth of the stars 22, 23 without touching any teeth of these teeth and thus without changing the angular position of the said stars. The calendar cam 2 remains motionless until the first end 6 of the oblong opening 5 joins the pin 4, making the calendar cam 2 solidary of the calendar wheel 1 and the insulating cam 3 (figure 2c).Then the cam 8 swing comes into contact with the armament part 2a of the calendar cam 2 and is lifted by it (Figures 2(d) and 2(e)), and the calendar swing 16, whose beaks 20, 21 are now completely out of the teeth of the stars 22, 23, continues to move away from the stars 22, 23. The calendar swing 16, which from the beginning of the movement was guided by the pin 24 (Figures 2(a) to 2 (d)) is moving away from the latter (Figure 2 ((e)).the insulation swing 11 passes from the top 3c to the bottom 3b of the insulation cam 3 (Figure 2 ((f))), which brings the calendar swing 16 closer to the stars 22, 23. Then, at midnight, it is the swing cam 8 that passes the top 2c of the calendar cam 2, makes it rotate abruptly under the action of the spring 10 (which is made possible by the cooperation between the pin 4 and the oblong opening 5) and, by falling, drives the calendar swing 16 whose nozzles 20, 21 fit into the teeth of the stars 22, 23 by turning the stars 22,23 of a step (Fig. 2(g)). For the understanding of the drawings only, a tooth 25, 26 of each of the stars 22, 23 has been highlighted to show that the position of the stars 22, 23 has changed in Figure 2(g) compared to Figures 2(a) to 2(f).

Figures 3 (a) to 3 (h) show different successive configurations of the calendar mechanism according to this first embodiment of the invention during a time-reversal, i.e. in the anti-clockwise direction of the time-display indicators, where the calendar wheel 1 and with it the insulation cam 3 rotate in a direction S2 opposite to the direction S1.23 respectively, the cam 8 swing is out of contact with the calendar cam 2 because held against the action of spring 10 by the calendar swing 16 which cooperates with the pin 19, the insulation swing 11 is applied against the lower part 3b of the insulation cam 3 and the pin 4 is away from the ends of the oblong opening 5, especially the second end 7. The insulation swing 11 is lifted from the lower part 3b to the top 3c of the insulation part 3 by the drop cam 3d (Figure 3 ((b)) which brings out the nozzles 20,21 of the calendar swing 16 of the star teeth 22, 23 without touching any of these teeth and thus without changing the angular position of the stars 22, 23, then begins to descend along the 3a part of the insulating cam 3. The calendar cam 2 remains fixed until the second end 7 of the oblong opening 5 joins the pin 4, then making the calendar cam 2 solidary to the calendar wheel 1 (Figure 3 (((c)).Calendar Rocker 16, which from the beginning of the movement was guided by the pin 24 (Figures 3 ((a) to 3 ((d))), moves away from the latter (Figure 3 ((e)). When the Rocker 8 reaches the peak 2c of the Calendar Rocker 2 (Figure 3 ((e))), the Rocker 16 is further away from the stars 22, 23.23 by the cooperation between pin 19 and the oblong opening in U 18. The cam swing 8 and the insulation swing 11 continue their descent along the calendar swing 2 and the insulation swing 3 respectively (Figure 3 ((g)) until they reach the position described in relation to Figure 3 ((a) where the cam swing 8 is out of contact with the calendar swing 2 and the insulation swing 11 is on the lower part 3b of the insulation swing 3 (Figure 3 ((h)).23 without pulling them in, i.e. resuming their position from Figure 3 (a) without changing the angular position of the stars 22, 23.

Thus, during each 24-hour period, from midnight to midnight, during the normal operation of the watch or during a forward clock, the calendar pendulum 16 makes a forward movement which brings its beaks 20, 21 out of the teeth of the stars 22, 23 without touching any teeth of these teeth and thus without changing the angular position of these stars, then a backward movement which brings its beaks 20, 21 into the teeth of the stars 22, 23 by moving the said stars forward one step.

This is made possible by the fact that, thanks to the oblong aperture 5, the two cams 2, 3 have relative angular positions which differ according to the direction of rotation of the calendar wheel 1 (see Figure 3c) compared to Figure 2c) and that, therefore, the movement of the calendar pendulum 16 differs according to the direction of rotation of the calendar wheel 1. An important feature of the present invention is that given the trajectory followed by the beams 20, 21 of the calendar pendulum 16 these do not need to be pivoted, as they can be inert. The effect of the stiffness of the pendulums at the moment of their change is to prevent the most inertial changes in the moment of their change.

The calendar mechanism according to this second embodiment differs from the calendar mechanism according to the first embodiment in that the cam 8 swing is removed and that the calendar swing, designated by the 16' mark, cooperates with the cam 2' instead of the cam 8 swing, has a 14' pebble or beak for this purpose and is directly subjected to the action of a booster spring 10'. Although not represented in Figure 4, a booster spring could also act on the insulation spring 11'. The respective shapes of the cam 2's insulation swing 3', the cam 16's cooperator and the cam 11's calendar swing are slightly unchanged from the first cam 3's insulation swing and are not altered by the other shapes of the cam 16's insulation swing.

According to the same principle as the movement described in relation to Figure 2, during each 24-hour period, from midnight to midnight, during normal operation of the watch movement or during a forward time, the 16' calendar pendulum, carried by the 11' insulation pendulum and guided at certain times by the 24 pin, makes a forward movement which brings its 20', 21' beaks out of the teeth of the stars 22, 23 without touching any of these teeth and thus without changing the angular position of the said stars, a movement which then brings its 20', 21' beaks back into the teeth of the stars 22, 23 and advances the said stars one step further. Figures 5a) to 5h) show different successive configurations of the calendar during this movement.

According to the same principle as the movement described in relation to Figure 3, on each 24-hour period from midnight to midnight but in the reverse direction, during a time-reversal, the 16' calendar pendulum makes a forward motion which takes its 20', 21' beak out of the teeth of the stars 22, 23 without touching any of these teeth and thus without changing the angular position of the said stars, and then a return motion which takes its 20', 21' beak in into the teeth of the stars 22, 23 without changing the angular position of the latter and thus without making any change in the display of the calendar. Figures 6a) to 6g) show different successive configurations of the mechanism of the calendar during this movement.

The second method of calculating the calendar has the advantage of having fewer parts than the first method, but the latter has several advantages: It makes it easier to control the balance between the spring booms of the swings; it avoids the use of a spring booster for the calendar swing, a spring booster whose support on the swing generates friction due to the translation component involved in the movement of this swing; it allows the use of a smaller calendar cam.

With the calendar mechanism as described above, depending on the first or second embodiment, a quantum or day-independent correction of the time display is prevented when the nozzles 20, 21 of the calendar switch 16 are engaged in the star 22-23 hinge, since these nozzles 20, 21 block the rotating stars 22, 23.

The correction device consists, as shown in Figure 7, of the watch movement's crankshaft 27 which can take three axial positions, namely a crankshaft position (push position), a quantium correction position (intermediate position), and a timing position (drawn position). A stroke 28 cooperates with the crankshaft 27 to control the running gear (not shown) in the traditional manner. In the present invention stroke 28 also controls a lever 29 by means of a pin 30 solidary to stroke 28 and engaged in an oblong opening 31 cubits from the lever 29.Lever 29 pivots at a point 32. A lever 33 is articulated at one end to lever 29 and at the other end to a first end 34 of a second lever 35. Lever 35 pivots around the common axis of rotation of the calendar wheel 1 and cams 2, 3 and has a second end 36 on the other side of that axis from the first end 34. When the lift rod 27 is in the lifting or timing position, levers 29, 35 and lever 33 are in their position shown in full in Figure 7.where the lever 35 does not act on the insulation swing 11 which remains against the insulation cam 3. When the mounting rod 27 is in the quantum correction position, the levers 29, 35 and the bearing 33 are in their position shown in dotted line, where the insulation swing 11 is lifted and removed from the insulation cam 3 by the action of the second end 36 of the lever 35 on a pin 11a carried by the insulation swing 11. In this position, the nozzles 20, 21 of the calendar swing 16 are outside the star 22 denture.The fact that the levers 29, 35 and the handle 33 are in the same position in the lifting or timing position of the lifting rod 27 is made possible by the elongated shape of the oblong opening 31. In the quantum correction position of the lifting rod 27, the pin 30 is at the elbow of the opening 31.between the quantum correction position and the timing position, the pin 30 cooperates with the other portion 38 of the aperture 31, from the elbow to the second end of the aperture.

Another part of the correction device is shown in Figure 8. This part concerns the correction of days. A day 39 corrector, which is in the form of a lever operated by a push button (not shown) and rotating at a point 40, has a beak 41 that moves the day 23 star one step each time the day 39 corrector is operated. The corrector 39 is subjected to the action of a recall spring (not shown). The corrector has a pin 42 that lifts the insulation swing 11 at each actuation of the corrector 39. The lifting of the insulation swing 11 pulls the calendar swing 16 away from the stars 22, 23, and in particular pulls the tooth 21 out of the 23 day star beak before the day 39 corrector 41 enters the beak.

The calendar mechanism of the invention may also include a month indicator. Figure 9 shows an example of such an indicator, in the form of a disk 43 showing the indications of the 12 months. This indicator 43 is solidary of a month gear 44 which is driven by a gear 45 itself driven by a retractable finger 46 carried by the quantum star 22.^{- What ?}If a correction of the month display by an unrepresented mechanism is made while the finger 46 is engaged in a gear of gear 45, the finger 46 retracts to prevent any blockage of the month display 44. The mechanism for correction of the month display is for example a gear connected to the spring rod by a swing so that when the spring rod is in the axial position of the quantum correction, a rotation of the rod in one direction corrects the angular position of the month gear 44 while rotation of the rod in the other direction corrects the angular position of the 22nd wheel by means of the said rotation and a basic quantile of the quantum correction.

The present invention has been described above as an example only. It is clear that modifications could be made without going beyond claim 1. For example, if the function of not allowing the stars 22, 23 to operate during a time-reversal is not desired, then two solid cams rotating one another, i.e. without relative rotation range, may be used. Furthermore, the cams may not be coaxial.

In the following claims, the term pivot is to be considered broadly, as covering not only the material axis on which a given swing is mounted but also, more generally, the imaginary axis around which the swing pivots.

Claims (10)

1. Mechanism for driving an indicator for a timepiece, comprising:

   - a mobile (22; 23) for driving the indicator,

   - a first lever (16) mounted about a first pivot (17) and comprising a beak (20; 21) intended to cooperate with teeth on the mobile (22; 23) in order to displace said mobile,

   - a first cam (2) arranged to cause the first lever (16) to turn about the first pivot (17),

   - a second lever (11) mounted about a second pivot (12) and relative to which the first pivot (17) is fixed,

   - a second cam (3) arranged to cause the second lever (11) to turn about the second pivot (12), and

   - elastic means (10, 13) to maintain the cooperation between the levers (16, 11) and the cams (2, 3),

   the levers (16, 11) and the cams (2, 3) being arranged so that the beak (20; 21) of the first lever (16) cyclically describes a closed curve, each cycle comprising a first movement during which the beak (20; 21) exits the teeth of the mobile (22; 23) without modifying the angular position of said mobile and a second movement during which the beak (20; 21) reenters the teeth of the mobile (22; 23) in order to displace said mobile.
2. Mechanism as claimed in claim 1, wherein the beak (20; 21) is non-retractable.
3. Mechanism as claimed in claim 1 or 2, wherein the levers (16, 11) and the cams (2, 3) are arranged so that the mobile (22; 23) is displaced by instantaneous jumps.
4. Mechanism as claimed in any one of claims 1 to 3, wherein the first and second cams (2, 3) are coaxial.
5. Mechanism as claimed in any one of claims 1 to 4, further comprising a third lever (8) mounted about a third pivot (9) and arranged so that the first lever (16) is driven by the first cam (2) via this third lever (8).
6. Mechanism as claimed in any one of claims 1 to 5, further comprising a device (28-36; 39-42) to cause the beak (20; 21) to exit the teeth of the mobile (22; 23) automatically before a correction of the position of said mobile.
7. Mechanism as claimed in claim 6, wherein said device (28-36) can be actuated by a displacement of a winding stem (27) into a predetermined axial position.
8. Mechanism as claimed in claim 6 or 7, wherein said device (28-36; 39-42) comprises means (35, 36; 42) to move the second lever (11) away from the second cam (3), this distancing movement causing a displacement of the first lever (16) causing the beak (20; 21) to exit the teeth of the mobile (22; 23).
9. Calendar mechanism for a timepiece comprising a mechanism as claimed in any one of claims 1 to 8.
10. Timepiece comprising a mechanism as claimed in any one of claims 1 to 9.