EP0549941B1 - Mechanical and/or electromechanical timepiece provided with automatic retrograde display means - Google Patents

Description

The present invention relates to a timepiece of the mechanical and / or electromechanical type.

More particularly, it relates to a timepiece comprising display means with automatic retrograde movement, that is to say capable of returning in reverse towards a point of origin after having made a movement on a race, by circular example, predetermined.

Displays of this type are used to provide analog information, such as for example hours, minutes, seconds, date or the like.

These display means are also known in watchmaking under other names, such as sectoral or oscillating displays.

Patent CH-27961 discloses a timepiece comprising display means with retrograde movement which allow the hours and minutes to be read on arcs of a circle formed on a dial, by means of two hands returning to their point of origin after reaching divisions 12 and 60 respectively. This timepiece meets the definition given above.

This part comprises a first drive gear formed by a wheel which is driven by a fully mechanical horometric movement and which meshes with a toothed sector, itself engaged with a wheel secured to a barrel carrying a minute hand. The hour hand is carried by another canon which is, as for him, directly arranged on a sector engaged with a second reference.

Each reference has in its thickness a clearance formed by a notch in the form of a tab. This notch opens radially at the periphery of the return, close to its teeth intended to mesh with the sector.

Thus, after each complete rotation in a first direction, known as the driven direction, the clearance occurs with respect to the sector which is thus freed from the deflection and which, thanks to an elastic return means, performs an automatic movement in a reverse direction of rotation at first. Furthermore, the sector has a stop, while the return comprises a counter-stop, this stop and this counter-stop being shaped to come into contact in order to limit the angular displacement of the sector and to precisely re-align the needle. corresponding to its original position relative to the dial. The stop which is formed on the sector is constituted by a heel whose height is twice greater than that of the teeth and therefore that of the body of the sector. The counter-stop is constituted by a deflection tooth which is located above the clearance, on a level higher than the meshing teeth of the sector.

It is therefore understood that the return must have a sufficient thickness to be able to receive the clearance formed therein and to leave a tooth forming against stop which is sufficiently rigid in shear to accept the dynamic force undergone by the contact of the stop. formed by the heel, at the end of the movement in the retrograde direction.

It is also understood that the heel itself must have a sufficient thickness or protrude sufficiently from the meshing teeth of the sector, to come to cooperate with the counter-stop.

Thus, this arrangement has the essential drawback of being relatively bulky in thickness. This arrangement was designed to apply to a watch movement such as a pendulum or a clock, and this is the reason why the manufacturers of the time had not been concerned to reduce the 'thickness. This arrangement cannot therefore be integrated into a modern mechanical and / or electromechanical timepiece in which, as we know, it is also necessary to provide space for other large volume components, such as the battery or additional mechanisms. date indication, or even chronograph.

In addition, this prior arrangement requires the machining of the reference for the realization of the miter clearance. This special operation, as well as that for producing the heel, is costly and significantly increases the price of the equipped part.

Furthermore, according to patent CH-143 441, a timepiece is known, a hand of which, in particular the hour hand, is also mounted integral with a toothed sector which is intended to cooperate with a reference in which a clearance similarly constituted by a miter notch directly machined in this reference. In this arrangement, the stop and the counter-stop are respectively constituted by a beam of considerable length and by an axis which are attached respectively to the toothed sector and to the gear. The axis is arranged tangent to the clearance.

Here too, the stop and the counter stop protrude axially from the sector and from the return and they occupy an important place in thickness.

Finally, there is known from patent CH-61,478 a calendar watch, a hand of which is mounted on a calendar wheel which lacks a certain number of teeth, this wheel being driven in rotation by means of a pin mounted on a return.

Thus, when the needle has finished its travel in the direction of driven movement, the pin is inside the clearance formed by the absence of teeth on the date wheel and the movement of this wheel as well as that of the 'needle are stopped, failing to catch with the return. In addition, the date wheel meshes with a manual actuation wheel on which a bare sector is formed, the diameter of which is substantially identical to the head diameter of the teeth of the actuation wheel. The latter allows, thanks to its bare non-toothed part, to form a stop limiting the angular displacement of the date wheel.

Thus, this arrangement is not automatic and it requires the use of an additional actuating wheel which again increases the manufacturing costs. In addition, this wheel does not provide sealing and exposes the movement to dust and impurities since it projects from the box to be externally accessible. We can also observe that the reference must have a significant reduction since it must make one revolution for each step of the calendar hand, this because of the drive pin.

Thus, the present invention aims to overcome the drawbacks of the prior art mentioned above, by providing a timepiece provided with display means with fully automatic retrograde movement, of thickness as low as possible to reduce the overall height, in particular in order to be able to equip standard movements having a determined thickness.

The present invention also aims to provide a timepiece of this type whose manufacturing and assembly costs are as low as possible.

• un mouvement horométrique,
• un renvoi entraîné par le mouvement horométrique et comportant des dents d'engrènement,
• des moyens d'affichage à déplacement rétrograde automatique, ces moyens comprenant :
• un système d'affichage d'informations telles que par exemple la date,
• au moins un élément oscillant associé audit système d'affichage et comportant des dents, les dents d'engrènement du renvoi étant aptes à venir en prise avec lesdites dents d'engrènement de l'élément oscillant pour l'entraîner en rotation, les dents d'engrènement du renvoi et celles de l'élément oscillant étant respectivement menantes et menées,
• des moyens de rappel de l'élément oscillant,
• des moyens de débrayage pour interrompre de façon au moins temporaire l'engrènement entre les dents menantes et les dents menées et pour permettre à l'élément oscillant d'effectuer un déplacement libre, dit rétrograde, lesdits moyens de débrayage étant constitués par au moins un dégagement formé dans les dents menantes, et
• une butée associée à une contre-butée pour limiter le déplacement rétrograde de l'élément oscillant, ladite butée étant solidaire de l'élément oscillant tandis que la contre-butée est solidaire du renvoi, cette pièce d'horlogerie étant caractérisée en ce que ladite contrebutée est constituée par l'une des dents d'engrènement menantes du renvoi engrènant normalement, lors de l'entraînement, avec les dents menées de l'élément oscillant.

To this end, the subject of the present invention is a timepiece of the mechanical and / or electromechanical type comprising:

• a horometric movement,
• a reference driven by the horometric movement and comprising meshing teeth,
• display means with automatic retrograde movement, these means comprising:
• a system for displaying information such as for example the date,
• at least one oscillating element associated with said display system and comprising teeth, the meshing teeth of the return being able to engage with said meshing teeth of the oscillating element to drive it in rotation, the teeth d meshing of the reference and those of the oscillating element being respectively driving and driven,
• means for returning the oscillating element,
• declutching means for interrupting at least temporarily the engagement between the driving teeth and the driven teeth and for allowing the oscillating element to perform a free movement, called retrograde, said declutching means being constituted by at least one clearance formed in the leading teeth, and
• a stop associated with a counter stop to limit the retrograde movement of the oscillating element, said stop being integral with the oscillating element while the counter stop is integral with the reference, this timepiece being characterized in that said buttressed is constituted by one of the driving meshing teeth of the return meshing normally, during the drive, with the driven teeth of the oscillating element.

According to a particular embodiment, the clearance which constitutes the declutching means is defined in length essentially by two driving teeth, called end teeth, one of these end teeth forming said counter-stop.

According to yet another characteristic of the invention, the driving tooth forming the counter-stop has at least in plan an identical shape, and a thickness equal to that of the other driving engagement teeth.

Furthermore, the stop substantially protrudes from the teeth of the oscillating element, depending on their height, to cooperate with the driving engaging tooth forming the counter-stop.

• la figure 1 est une vue de dessus d'une pièce d'horlogerie comportant des moyens d'affichage à déplacement rétrograde selon l'invention;
• la figure 2 est une vue de dessus représentant plus particulièrement les moyens d'affichage selon l'invention, et dans laquelle une plaque de support ainsi que le cadran, visible à la figure 1, sont représentés partiellement et de façon arrachée, tandis qu'une aiguille de quantièmes, qui est dans une position d'origine (en regard du chiffre 1) est représentée en traits mixtes interrompus;
• la figure 3 est une vue similaire à la figure 2, mais dans laquelle les moyens d'affichage sont dans une position angulaire plus avancée où l'aiguille des quantièmes est positionnée en fin de course (en regard du chiffre 31);
• la figure 3A est une vue en coupe d'un élément oscillant selon l'invention faite selon les flèches A-A de la figure 3;
• la figure 4 est une vue similaire à la figure 2, mais représentant un deuxième mode de réalisation de l'invention;
• les figures 5 et 6 sont respectivement des vues de dessus et de dessous de la plaque de support vue partiellement sur les figures 2 à 4, et sur laquelle sont montés les moyens d'affichage selon l'invention;
• les figures 7 et 8 sont des vues en coupe faites respectivement selon les lignes VII-VII et VIII-VIII des figures 6 et 5;
• la figure 9 est une vue similaire à la figure 2, mais dans laquelle les moyens d'affichage selon l'invention sont recouverts d'une plaque de montage et de maintien.

However, the invention will be better understood on reading the detailed description which follows, taken with reference to the appended drawings which are given solely by way of example, and in which:

• Figure 1 is a top view of a timepiece comprising display means with retrograde movement according to the invention;
• FIG. 2 is a top view showing more particularly the display means according to the invention, and in which a support plate as well as the dial, visible in FIG. 1, are partially and cut away, while a date hand, which is in an original position (opposite the number 1) is shown in broken dashed lines;
• FIG. 3 is a view similar to FIG. 2, but in which the display means are in a more advanced angular position where the date hand is positioned at the end of the stroke (opposite the number 31);
• FIG. 3A is a sectional view of an oscillating element according to the invention made according to the arrows AA of FIG. 3;
• Figure 4 is a view similar to Figure 2, but showing a second embodiment of the invention;
• Figures 5 and 6 are respectively top and bottom views of the support plate partially seen in Figures 2 to 4, and on which are mounted the display means according to the invention;
• Figures 7 and 8 are sectional views taken respectively along lines VII-VII and VIII-VIII of Figures 6 and 5;
• Figure 9 is a view similar to Figure 2, but in which the display means according to the invention are covered with a mounting and holding plate.

Referring to FIG. 1, there will be described below sectorial display means of data or display means with retrograde movement, identified by the general reference 1. The display means 1 which equip a timepiece referenced P are intended to provide information in analog form, such as the date and in particular the dates.

The timepiece P is, in this example, constituted by a wristwatch of the mechanical and / or electromechanical type comprising a strap 2 which is here partially shown and which is mounted on a case 4.

The timepiece P comprises a dial 6 on which are written in particular indications of hours and minutes, identified respectively by a first group of numbers 1 to 4 and 8 to 12 and by a graduated circular scale, not referenced. Next to the dial 6 are arranged three hands, respectively of hours 8, minutes 10 and seconds 12 which are driven by a horometric movement, not shown, conventionally mounted in the case 4 and which can be actuated manually by a crown 14. Needles 8, 10 and 12 can move in rotation coaxially around a first axis of rotation X1, centered on the movement of the part P.

The sectoral or retrograde displacement display means 1 according to the invention comprise, in a visible manner in this figure, an information display system 16 which is constituted by a needle 18 shaped to move angularly opposite a annular sector 20 inside which data is written, and in particular in this example a second group of figures of the odd type, 1 to 31, indicating the date of the month.

As will be understood below, the hand 18, which is kinematically linked to the horometric movement of the timepiece P, is in its original position on the first day of the month, opposite the indication 1 and it jumps a step every day, especially around midnight, thanks to the means in their major conventional part that we will not describe in detail here.

In the simplest version of the timepiece according to the invention, the date hand 18 continues its advance until it comes opposite the number 31 where it reaches its position of final angular displacement.

Instead of taking a next step, the needle 18 automatically moves in the opposite direction to its original position. This needle 18 therefore performs a so-called retrograde movement. This movement being effected only on a fraction of a turn, and in particular in this example over an angle of approximately 330 °, it is understandable why the display means 1 according to the invention are also qualified as sectoral display means.

Referring now to Figures 2 and 3, we will describe in more detail the mechanical arrangement of the display means according to the invention.

In these figures, the dial 6 and a support plate 50 have been shown partially and torn off. Also found in these figures the needle 18 which is shown here in broken dashed lines.

The display means 1 according to the invention comprise a reference or driving pinion 22 which is mounted for rotation about the central axis X1 and which is integral with a driving star 24 comprising in this example 31 teeth. This star is driven in a conventional manner by the horometric movement not shown and it is associated with a jumper spring also conventional, likewise not shown.

The reference 22 includes meshing teeth 26a, 26b up to 26y, in this example 25 in number, these teeth being identified by the general reference 26a-26y (26a to 26y).

The sectoral or retrograde display means 1 additionally comprise an oscillating element 30 which is associated with the display system 16 via an axis, not referenced, on which the needle 18 is conventionally driven out.

The oscillating element 30 is constituted by a wheel, and in particular by a date wheel (same reference) which is rotatably mounted around a second axis of rotation X2 offset from the first X1 and which comprises meshing teeth identified by the general reference 32.

As can be seen more particularly in FIG. 3, the meshing teeth 26a-26y of the reference 22 are able to come into engagement with the meshing teeth 32 of the oscillating element 30 in order to drive it in rotation over a fraction. angle corresponding to the arc of the annular display sector 20. The engine torque being received from the movement of the timepiece P via the gear 22, it is understood that the meshing teeth 26a-26y of the gear 22 and the meshing teeth 32 of the oscillating element 30 are respectively driving and driven.

Furthermore, the display means 1 comprise means 34 for elastic return of the oscillating element 30, these means 34 being constituted by a spiral spring (same reference), one end of which is integral with the oscillating element 30 by being fixed for example on its support axis not referenced, while the other end is held fixed relative to the box, by being fixed directly for example on the support plate 50 shown in more detail in FIGS. 5 to 8. The return means 34 are arranged so that the oscillating element 30 is returned elastically to its original position, shown in Figure 2, that is to say in its retrograde direction of movement (counterclockwise in this example).

The display means 1 further comprise declutching means 40 shaped to at least temporarily interrupt the engagement between the driving teeth 26a-26y and the driven teeth 32 and, as will be understood, to allow the element oscillating 30 to freely carry out its retrograde movement.

The declutching means 40 are constituted by a clearance (same reference) formed in the driving teeth 26a-26y. This clearance 40 therefore corresponds to a toothless zone, forming a bare or smooth annular sector, on the reference 22.

Thus, in the position shown in FIG. 2, the teeth 32 of the oscillating element 30 are no longer in normal engagement with those, 26a-26y, of the reference 22. Thus, when the clearance 40 occurs opposite the driven teeth 32, the oscillating element 30 is released from its kinematic connection with the reference 22, and therefore with the horometric movement of the timepiece P according to the invention.

However, the oscillating element 30 is permanently resiliently returned by the spring 34 to its original position in the direction of counterclockwise movement and its angular displacement in this direction is limited to this original position by a stop. B and by a counter stop CB display means 1 according to the invention.

The stop B is secured to the oscillating element 30, while the counter stop CB which is formed by one (referenced 26a) of the engagement teeth 26a-26y, is secured to the reference 22.

Thus, the counter-stop CB by being constituted by one, 26a, of the driving meshing teeth 26a-26y of the return 22 normally engaging, during the drive, with the driven teeth 32 of the oscillating element 30, does not require any additional machining or assembly operations, in particular on the return 22.

The clearance 40 which constitutes the declutching means has an arc length, not referenced, defined essentially by two of the driving teeth respectively 26a and 26y, called extreme teeth, one, 26a, of these extreme teeth forming in particular said counter CB stop.

It will be noted in the figures that the driving tooth 26a forming the counter-stop CB has at least in plan a shape identical to that of the other driving engaging teeth 26b to 26y. More particularly, it will be specified that this tooth 26a has a thickness equal to that of the other driving meshing teeth 26b to 26y.

The stop B, in turn, substantially protrudes from the driven teeth 32 of the oscillating element 30, according to their height h (Figure 2) to come to cooperate with the tooth 26a forming the counter-stop CB.

It will also be noted that, as seen in FIG. 3A, the stop B is formed essentially in the thickness of the oscillating element 30.

More particularly, and as can be seen in this figure, the stop B has a thickness E1 equal to that, E2, of the teeth 32.

FIG. 4 represents a second embodiment of the invention, in which the reference 22 comprises two groups G1 and G2 of driving teeth, these groups being separated by an equal number of clearances, respectively 40 and 40a. The angular travel of the needle 18 is therefore here much more limited, and this needle performs two round trips for a complete rotation of the return 22. The number of clearances as well as the number of distinct groups of driving teeth are not limited to two and can be extended to larger numbers respectively.

It will be specified that in all the examples described, and as seen in FIG. 34A, the stop B as well as the engaged meshing teeth 32 of the wheel forming the oscillating element 30 are inscribed in the thickness E2 of the board P forming said wheel. The stop B can therefore be provided by the same machining and stamping operations as those necessary for the production of the teeth 32, without additional operation.

Furthermore, and as can be seen in FIGS. 2 and 4, the stopper B has a profile having a reentrant lateral flank FL (FIG. 3) able to cooperate with the driving tooth 26a forming the counter-stopper B. Thus, when the the needle 18 has returned to its original position after its retrograde movement, the oscillating element 30 is again driven in rotation in its clockwise direction by the action of the tooth 26a on the reentrant lateral flank FL.

It can also be seen that the stop B is constituted by a sector S projecting from the top of two half teeth of the driven teeth 32 of the oscillating element 30.

The stopper B is produced simultaneously with the manufacture of the engaging meshing teeth 32 of the oscillating element 30. For this, the wheel forming this oscillating element 30 is cut to an outside diameter greater than the head diameter of the teeth 32. This supplement diameter corresponds to twice the height H (Figure 3) of the stop B. Then, the teeth 32 are formed in the board P using a conventional size cutter, not shown, but only on a given angular part to allow to remain and reveal, in the wheel 30, the stop B.

The invention further comprises a support plate 50, shown in more detail in FIGS. 5 to 8, on which the oscillating element 30 is pivotally mounted.

This support plate 50 is intended to be mounted and fixed, by its lower face FI (FIGS. 6 and 7), on a plate of the horometric movement not shown of the timepiece P according to the invention. This plate 50 has two recesses 52 and 54 opening radially into one another. The first recess 52 receives the reference 22, while the second, 54, receives the oscillating element 30. For this purpose, the second recess 54 has a tongue or projection 56 on the free end of which the oscillating element 30 is supported cantilevered and rotatable. The tongue 56 projects diametrically in the second recess 54 toward its center intended to come into coincidence with the second axis of rotation X2.

It will be noted that the plate 50 has a third recess 59 formed on the side of the face FI and into which the other two recesses 52 and 54 open axially.

As can be seen in FIG. 9, the invention also comprises a second plate 60 fixed to the first, 50.

This second plate 60 is fixed, by means of screw-tapping systems 62 above the oscillating element 30, in a fourth recess 58 formed in the first plate 50, above the second obviously 54 and so coaxial with it.

The second plate 60 has a through circular groove 64 into which a tool, not shown, can be inserted, intended to arm the oscillating element 30 by putting under tension its return means 34.

Claims (14)

1. Timepiece of the mechanical and/or electromechanical type comprising :

   - a horometric movement,

   - an intermediate wheel (22) driven by the horometric movement and including gear teeth (26a-26y),

   - automatic backward moving display means (1) including :

   - at least one oscillating element (30) associated with said display system (16) and including gear teeth (32), the gear teeth (26a-26y) of the intermediate wheel (22) being adapted to come into mesh with the gear teeth (32) of the oscillating element (30) so as to drive it in rotation, the gear teeth of the intermediate wheel (22) and those of the oscillating element (30) being respectively driving and driven teeth,

   - return means (34) for the oscillating element (30),

   - declutching means (40, 40a) for interrupting, in at least a temporary manner, meshing between the driving teeth (26a-26y) and the driven teeth (32) and in order to enable the oscillating element (30) to effect a free backward motion, said declutching means (40, 40a) being formed by at least one cut-away segment formed in the driving teeth (26a-26y), and

   - an abutment (B) associated with a counter-abutment (CB) to limit the backward movement of the oscillating element (30), said abutment (B) being fixed to the oscillating element (30) while the counter-abutment (CB) is fixed to the oscillating element (30) while the counter-abutment (CB) is fixed to the intermediate wheel (22), this piece being characterized in that said counter-abutment (CB) is formed by one (26a) of the driving teeth (26a-26y) of the intermediate wheel (22) which, during driving, normally meshes with the driven teeth (32) of the oscillating element (30).
2. Timepiece according to claim 1, characterized in that the cut-away segment (40, 40a) which forms the declutching means has its length defined primarily by two (26a, 26y) of the driving teeth (26a-26y) referred to as end teeth, one (26a) of said end teeth (26a, 26y) forming said counter-abutment.
3. Timepiece according to claim 1 or 2, characterized in that the driving tooth (26a) forming the counter-abutment (CB) has, at least in plan view, a shape identical to that of the other driving gear teeth (26a-26y).
4. Timepiece according to one of claims 1 to 3, characterized in that the driving tooth (26a) forming the counter-abutment (CB) shows a thickness (E1) equal to that (E2) of the other driving gear teeth (26b-26y).
5. Timepiece according to claim 1, characterized in that said abutment (B) projects substantially beyond the height of the driven teeth (32) on the oscillating element (30) in order to come into cooperation with the driving gear tooth (26a) forming the counter-abutment (CB).
6. Timepiece according to claim 5, characterized in that said abutment (B) is arranged primarily within the thickness of the oscillating element (30).
7. Timepiece according to claim 5, characterized in that said abutment (B) shows a thickness equal to that of the driven gear teeth (32).
8. Timepiece according to one of the preceding claims, characterized in that said intermediate wheel (22) includes at least two groups (G1, G2) of driving tooth separated by an equal number of cut-away segments (40, 40a).
9. Timepiece according to one of the preceding claims in which the oscillating element (30) is a wheel, characterized in that said abutment (B) and said driven teeth (32) on such wheel are cut in the thickness of the plate (P) forming said wheel.
10. Timepiece according to one of the preceding claims, characterized in that said abutment (B) includes a profile showing a re-entrant lateral flank adapted to cooperate with the driving tooth (26a) forming the counter-abutment (CB).
11. Timepiece according to one of the preceding claims, characterized in that said abutment (B) is formed by a segment projecting from the summits of two half teeth from the driven teeth (32) of the oscillating element (30).
12. Timepiece according to one of the preceding claims, characterized in that it includes at least one support plate (50) intended to be secured onto the horometric movement, such plate (50) including at least two cutouts (52, 54) opening into one another, a first cut out (52) receiving said intermediate wheel (22) and a second cutout (54) receiving the oscillating element (30) such second cutout (54) including a tongue (56) which projects diametrally therein towards the center thereof, such tongue (56) supporting said oscillating element (30).
13. Timepiece according to claim 12, characterized in that said oscillating element (30) is supported in cantilever on the tongue (56).
14. Timepiece according to claim 13, characterized in that it includes a second plate (60) fixed to the first plate (50) above the oscillating element (30) , such second plate (60) including a circular open slot (64) into which a tool may be introduced intended to cock said oscillating element (30) by placing its return means (34) thereof under tension.

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