EP1081563B1 - Bracelet type watch - Google Patents

Description

The present invention relates to a watch, in particular of the wristwatch type, comprising a display, for example an analog time display, an electronic circuit for controlling said display, a time-setting rod and at least two electrical contact elements. , each of them alternately opening and closing an electrical connection of said electronic circuit during the rotation of the time-setting rod so as to generate at least two electrical signals, formed of pulses, transmitted to said electronic control circuit, said time setting rod being formed of four zones, an area bearing a setting ring, two cylindrical guide zones and a helical zone.

There are currently many watches and, in particular, wristwatches having an analog time display and an electronic control of the functions of the watch. The English patent application published under No. 2,070,815 and the patent Switzerland No. 637,521 describe in particular such watches.

These watches have a time setting rod having a square section over part of its length. On this square section are disposed two cams which may in particular have a substantially square rectangular profile, triangular or ellipsoidal. These two cams are angularly offset relative to each other and are mounted on the rod so that the rotation of the time setting rod causes the cams to rotate. These cams are also arranged near two elastic conductive blades which alternately open and close electrical connections when they are displaced by the rotation of the cams. This has the consequence that during a rotation of the cams, electrical signals formed of pulses are generated, these signals transiting from the open state to the closed state and vice versa, in a time-shifted manner.

The angular offset of the cams and the fact of using two electrical contacts make it possible to discriminate the direction of rotation of the time-setting rod, in a known manner.

The time setting rod can generally be placed in different longitudinal positions, so as to access different functions of the watch. For this purpose, the cams are sliding on the square section of the time setting rod so that they always remain in front of the conductive blades, regardless of the longitudinal position of the time setting rod.

This embodiment has various disadvantages. The square section of the time-setting rod must be large enough to accommodate the cams. In addition, these cams occupy a large volume. This poses problems of available space, especially in small watches, such as ladies' watches or very flat watches.

The positioning of the cams on the rod must be carried out in a given orientation of the cams, so that the rotation of the rod in a given direction is not interpreted by the electronic circuit as a rotation in the opposite direction. On the other hand, given the size of the cams, it is clear that this assembly is complex.

The fact that the cams must stay in front of the conductive blades implies the installation of a cam-holding element in a given longitudinal position, whatever the longitudinal position of the time-setting rod. This element also complicates the assembly.

Finally, so that the cams can slide longitudinally on the time setting rod, they must be mounted on it with a certain clearance. This introduces a hysteresis in the electrical control signals and this hysteresis must be electronically, which complicates the overall signal processing.

The device for obtaining electrical control signals for an electronic watch described in the publication GB-A-2,070,815 is a device arranged to generate shift pulse trains out of phase with each other and which produce a signal indicating the direction of rotation of the rod. It comes in the form of two cams that actuate two flexible blades to create contact.

The device object of the publication FR 2,444,344 is also intended to produce digital pulses. This goal is achieved by the rotation of a helix wound around a stationary drive element, which creates contact with detectors.

The publication GB 2,071,888 relates to an electronic watch device which is a device for selecting or correcting information. This device comprises cams secured to the rod and which have a width such that the elastic contact blades are always facing these cams regardless of the position of the rod.

The present invention proposes to overcome these disadvantages by producing a watch having a time-setting rod not carrying cams, but whose access to functions is the same as for current watches with cams. In addition, the manufacture of this time-setting rod is faster and simpler, its assembly is faster and more accurate and it takes less volume while having a more precise function because the signal provided is without hysteresis and asks for less electronic processing.

This goal is achieved by a wristwatch as defined in the preamble and
characterized in that said time-setting rod is made in one piece and comprises, on at least a part of its length, in the helical zone, at least one helical profile which cooperates directly with said electrical contact elements for alternately opening and closing an electrical connection of the electronic circuit during the rotation of said time setting rod to generate the electrical signals which control the different functions of the watch, independently of the longitudinal position of said rod, and in that each electrical contact element cooperates with said helical zone of the time-setting rod for all the longitudinal positions of said time-setting rod, except at most one position of this rod.

According to a first embodiment, the time-setting rod comprises two helical profiles.

According to a second embodiment, the time-setting rod comprises three helical profiles.

These helicoidal profiles are advantageously angularly offset by a constant value.

According to a particular embodiment of the invention, each helical profile has a constant helix pitch.

The electrical contact elements are preferably separated by a given distance d.

According to a preferred embodiment, the helical pitch of the helical profiles, the angular offset of these profiles as well as the distance d between the electrical contact elements are determined so that the electrical signals formed by the opening and the alternative closure of each electrical contact element during the rotation at constant speed of the time-setting rod have a duty ratio of between 30% and 70%, and advantageously substantially equal to 50%.

The pitch of the helical profiles, the angular offset of these profiles as well as the distance d separating the electrical contact elements are advantageously determined so that the electrical signals formed by the opening and the alternative closure of each electrical contact element during constant speed rotation of the time-setting rod is substantially in quadrature.

• la figure 1 est une vue en perspective d'une tige de mise à l'heure et d'éléments associés à cette tige, tels qu'utilisés dans une montre selon la présente invention,
• la figure 2 est une vue similaire à celle de la figure 1, dans laquelle la tige de mise à l'heure est dans une position différente,
• les figures 3A, 3B, 3C et 3D sont des vues en coupe transversale de différents modes de réalisation de tiges de mise à l'heure telles qu'utilisées dans une montre selon l'invention,
• la figure 4 est une vue de détail d'éléments de contacts électriques tels qu'illustrés par les figures 1 et 2.
• les figures 5A, 5B et 5C illustrent trois positions différentes d'une tige de mise à l'heure selon un premier mode de réalisation,
• les figures 6A, 6B, 6C et 6D illustrent quatre positions différentes d'une tige de mise à l'heure selon un deuxième mode de réalisation, et
• les figures 7A et 7B illustrent des signaux électriques obtenus lors de la rotation à vitesse constante de la tige de mise à l'heure, dans deux sens de rotation différents.

The present invention and its advantages will be better understood with reference to various embodiments of the invention and the accompanying drawings in which:

• FIG. 1 is a perspective view of a time setting rod and elements associated with this rod, as used in a watch according to the present invention,
• FIG. 2 is a view similar to that of FIG. 1, in which the time setting rod is in a different position;
• FIGS. 3A, 3B, 3C and 3D are cross-sectional views of various embodiments of setting rods as used in a watch according to the invention,
• Figure 4 is a detail view of electrical contact elements as illustrated in Figures 1 and 2.
• FIGS. 5A, 5B and 5C illustrate three different positions of a time-setting rod according to a first embodiment,
• FIGS. 6A, 6B, 6C and 6D illustrate four different positions of a time-setting rod according to a second embodiment, and
• FIGS. 7A and 7B illustrate electrical signals obtained during rotation at a constant speed of the time-setting rod, in two different directions of rotation.

With reference to the figures and in particular to FIGS. 1 and 2, the watch 10 according to the present invention comprises, in particular, a display 11 such as an analog or digital time display, an electronic circuit 12 for controlling said display, an update rod hour 13 and two elements of electrical contacts 14, 14 '. In the embodiments shown, these electrical contact elements are elastic conductive blades.

The time setting rod 13 is formed essentially of four zones. An area 15 includes a time-setting ring 16 accessible from outside the watch case and allowing the user to move the time-setting rod in rotation and thus to access certain functions of the watch. the watch. The rod also comprises two cylindrical zones 17, 18 guiding the time-setting rod both in rotation and in translation. Finally, the time-setting rod comprises a zone 19 having at least one helical profile, this zone being hereinafter called helicoidal zone 19.

In the embodiments shown in FIGS. 3A to 3C, which are cross-sectional views of the helical zone 19 of different time-setting rods, this zone comprises three helical profiles 20, 20 ', 20 ".

Figure 3A illustrates a first embodiment of the helical zone 19 of a time-setting rod. This zone is a set surface, which means that each section perpendicular to the longitudinal axis of the rod is delimited by straight segments 21. This embodiment allows simple manufacture.

FIG. 3B illustrates an embodiment in which the sections of the helical zone 19 of the rod are delimited by arcs of circle 22.

Finally, in the embodiment illustrated by FIG. 3C, these sections are delimited by a slightly curved curve 23. It is clear that other shapes of curves could also be chosen. The shape of these sections is essentially determined by the method chosen for the manufacture of the time-setting rod.

The embodiment illustrated in FIG. 3D comprises two helical profiles 24, 24 'making it possible to move the electrical contact elements.

The operation of the helical zone 19 is explained in detail below with reference to FIGS. 5, 6 and 7.

Figure 4 illustrates the two elements of electrical contacts 14, 14 '. According to a particularly advantageous embodiment, these contact elements are formed of two elastic blades, electrically conductive and separated by a given distance d. These contact elements are preferably made in one piece so that the distance d between the two blades can not be changed during assembly in the watch. However, it is also possible to make the contacts independently and to maintain the distance d by mounting.

The elements of electrical contacts 14, 14 'are mounted in the watch so that they alternately open and close connections of the electrical circuit of the electronic circuit 12 depending on the portion of the helical profile that moves these contacts. This mounting of the electrical contact elements is similar to conventional mounting with two sliding cams.

Figures 5A, 5B and 5C illustrate a time setting rod in three different possible longitudinal positions.

In Fig. 5A, the time setting rod is fully pushed inward of the watch case. The two contacts 14, 14 'rest on the cylindrical zone 17 of the rod. The rotation of this rod does not lead to opening and / or closing of the electrical connections. This position therefore corresponds to a "neutral" position of the contacts. The diameter of the cylindrical zone 17 implies that the electrical connections are always established. In order to minimize the power consumption due to these connections, it is possible to provide the power off if the contacts remain stationary for more than a predetermined duration.

In Fig. 5B, the time setting rod is shown in a position slightly displaced outwardly of the watch case. The helical zone 19 is opposite the contacts 14, 14 '. The rotation of the rod causes the alternative opening and closing of each connection. This opening and closing generates pulsed electrical signals, which are used in the electronic circuit 12 of the watch so as to control different functions. The generation of signals, as well as the discrimination of the direction of rotation of the rod are discussed below with reference to Figs. 7A and 7B. The use of these signals to access functions of the watch is not discussed in detail, since these elements are well known to those skilled in the art.

Figure 5C illustrates the time setting rod in a position strongly displaced outward of the watch case. The helical zone 19 remains opposite the contacts 14, 14 '. Thus, electric signals formed of pulses can again be generated by the rotation of the rod, with an identical phase shift, thus independent of the axial position of this rod.

The embodiment illustrated by FIGS. 6A, 6B, 6C and 6D is similar to that of FIGS. 5A, 5B and 5C. The time setting rod 13 may, however, be moved in four different longitudinal positions. In the position illustrated in FIG. 6A, corresponding to the position of the rod pushed towards the inside of the watch, the contacts 14, 14 'are arranged in a cylindrical zone 17, but they are not displaced by this zone. In this position, the connections remain open continuously and therefore do not consume energy.

In the three other positions of the time-setting rod illustrated respectively by FIGS. 6B, 6C and 6D, the contacts 14, 14 'are opposite the helical zone 19, which makes it possible, as previously, to generate electrical signals by the rotation of the rod.

FIGS. 7A and 7B illustrate electrical signals obtained during a rotation at a constant speed of a time-setting rod as illustrated by FIG. 3A for example.

The upper part of these figures illustrate a signal generated by the contact element 14, while the lower part illustrates the signal generated by the contact element 14 '.

In order to allow reliable discrimination of the direction of rotation, it is essential that the signals generated during the rotation of the rod in one direction, differ from those generated during the rotation in the opposite direction.

In order to optimize this discrimination, it is desirable, but not necessary, for the duration during which each contact is closed to be substantially equal to the duration during which it is open. In this case, we are talking about a 50% duty cycle. In addition, it is also desirable that switching of one of the contacts occurs substantially in the middle of the period during which the other contact remains in a given stable state. For example, if a switch on one of the contacts occurs every 0.2 seconds, it is desirable that the switching of the other contact occurs every time 0.1 seconds after the switching of the first contact.

In this configuration, the electrical signals are said to be "quadrature". For a profile such as that of FIGS. 3A, 3B and 3C, this condition is fulfilled when the pitch of the section developed helically is such that the angle traveled circumferentially by a stop over a distance d is 30 °. For a profile such as that of Figure 3D, this step must be 45 °. This configuration makes it possible to minimize the risk of false switching detection, and thus to ensure that the electrical signals are correctly interpreted.

FIG. 7A illustrates, for example, the signals obtained during a clockwise rotation of the time-setting rod. From this figure, it can be seen that the transition from logic 0 to logic 1 of the first contact is followed by a transition from logic 0 to logic 1 of the second contact.

When rotating the time-setting rod counter-clockwise, as shown in Fig. 7B, the transition from logical state 0 to logic state 1 of the first contact is followed by a transition from logic 1 to logic 0 of the second contact.

By determining which transition occurs on the second contact when a transition from state 0 to state 1 occurs on the first contact, it is possible to determine the direction of rotation of the rod.

The present invention has many advantages over devices of the prior art.

The time setting rod 13 is made in one piece and does not include sliding elements such as cams or sliding gears. This reduces the number of parts to be made and greatly simplifies the assembly of the entire watch.

It is possible to provide that the helical zone 19 is a controlled surface, which also simplifies the manufacture of this rod.

In addition, the section of the helical zone 19 is large relative to the square section of the rods of the prior art. This improves the robustness thanks to a greater mechanical resistance for a smaller footprint.

The total length of the rod can also be reduced, since it is no longer necessary to take into account the games related to the sliding installation of the cams. This frees space in the watch, which is advantageous, especially in small watches.

The positioning of the contacts 14, 14 'need not be particularly precise. It is sufficient that the distance d between the contacts is consistent with the pitch of the helix of the helical zone of the rod. This is particularly simple to guarantee because of the manufacturing methods generally used to make the contacts.

Finally, since there is no angular clearance between the zones generating a displacement of the contacts and the rotation of the rod, the electrical signals do not exhibit hysteresis and are easier to process. This also allows a simplification of the electronic processing circuit.

The present invention is defined by claim 1. It is therefore not limited to the embodiments described, but extends to any variant or modification defined in this claim. In particular, the shape of the helical zone can be modified, as long as it makes it possible to move the contacts during the rotation of the rod. It is indeed possible to provide two or four helical profiles for example instead of the three profiles shown in Figures 3A to 3C.

In addition, the pitch of the helix may vary along the helical zone. This would determine the axial position of the time setting rod. Indeed, the offset between the signal generated by one of the contacts with respect to the shift of the signal generated by the other contact is different if the pitch of the helicoid in two helical zones is different. In particular, the signals may be in quadrature when the time-setting rod is in a first axial position and not in quadrature when the rod is in a second axial position. The analysis of the signals would thus make it possible to determine in which axial position the time-setting rod is located.

Claims (9)

1. A watch, especially a wristwatch, comprising a display (11), for example an analog time display, an electronic circuit (12) for controlling said display (11), a time set stem (13) and at least two electrical contact elements (14, 14'), each of them alternately opening and closing an electrical connection in said electronic circuit (12) when the time set stem (13) is rotated so as to generate at least two electrical impulse signals which are transmitted to said electronic control circuit (12), said time set stem (13) being formed of four zones (15, 17, 18, 19), one zone (15) provided with a time set crown (16), two guiding cylindrical zones (17, 18) and a helical zone (19), characterized in that said time set stem (13) is formed of a single piece and comprises, along at least a part of its length, in the helical zone (19), at least one helical portion (20, 20', 20"; 24, 24') which cooperates directly with said electrical contact elements (14, 14') to alternately open and close an electrical connection on the electronic circuit (12) when said time set stem (13) is rotated in order to generate the electrical signals that control the various functions of the watch, independently of the longitudinal position of said stem, and in that each electrical contact element (14, 14') cooperates with said helical zone (19) of the time set stem (13) for all the longitudinal positions of said time set stem (13), excepting a maximum of one stem position.
2. A watch according to claim 1, characterized in that the time set stem (13) comprises two helical portions (24, 24').
3. A watch according to claim 1, characterized in that the time set stem (13) comprises three helical portions (20, 20', 20").
4. A watch according to claim 2 or 3, characterized in that the helical portions (20, 20', 20") are angularly offset at constant intervals.
5. A watch according to claim 2 or 3, characterized in that each helical portion (20, 20', 20"; 24, 24') has a constant helix pitch.
6. A watch according to claim 1, characterized in that the electrical contact elements (14, 14') are separated by a given distance d.
7. A watch according to claims 4, 5 and 6, characterized in that the helix pitch of the helical portions (20, 20', 20"; 24, 24'), the angular separation of these portions, and the distance d separating the electrical contact elements (14, 14') are determined so that the electrical signals formed by the alternate opening and closing of each electrical contact element (14, 14') when the time set stem (13) is rotated at a constant speed have a cyclical relationship that ranges from 30% to 70%.
8. A watch according to claim 7, characterized in that the cyclical relationship is substantially equal to 50%.
9. A watch according to claims 4, 5 and 6, characterized in that the pitch of the helical portions (20, 20', 20"; 24, 24'), the angular separation of these portions and the distance d separating the electrical contact elements (14, 14') are determined so that the electrical signals formed by the alternate opening and closing of each electrical contact element when the time set stem (13) is rotated at a constant speed are substantially in quadrature.

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