This application claims priority from European Patent Application No. 12181207.7 filed Aug. 21, 2012, the entire disclosure of which is incorporated herein by reference.
The present invention relates to a correction device for changing the data of a plurality N of time-related functions displayed by a timepiece.
To perform these corrections, most timepieces employ a stem-crown which can be placed in first and second pulled-out positions to select the date and time-setting functions respectively, the correction being performed by rotating the crown. The advantage of this system lies in the two-directional correction of the data to be modified but the choice is limited to the correction of two functions. If other functions require correction, for example the day of the week and the month, a second stem-crown could be added to the middle part of the timepiece with the technical complications and lack of aesthetic appeal that this solution would involve.
The required corrections may also be implemented by pushers, each of which corrects a displayed item of time data. Often, these pushers are correctors embedded in the middle part of the timepiece, which does not detract from the aesthetic appeal of the assembly. However, the main drawback of this solution lies in its one-directional operation, along with the possibility of the mechanism breaking if two pushers are actuated at the same time.
Watchmakers therefore feel the need to design a system which associates pushers and stem-crowns, with the pusher selecting the function from among several available functions and the stem-crown correcting the function in both directions.
A draft of the aforecited system is proposed in CH Patent Application No 700531 A2. That Patent Application provides a pusher for changing function and a stem for correcting the selected function, with the stem being driven in rotation by a serrated ring which can be moved manually around the middle part of the timepiece. Each separate press on the pusher (i.e. a press, followed by a release of pressure) changes the function to be corrected by the ring. For example, starting from a winding function, a first press selects the time-setting function, a second press selects the date-setting function, and a third press will again select the winding function. The present system provides a device displaying the function fulfilled by the ring during rotation. This system is not dissimilar to a conventional watch control system since it uses a sliding pinion mounted on the stem. It will thus be clear that the number of functions displayed by the watch is limited to two units, namely setting the time and the date.
Thus, if a system is to be implemented which is capable of correcting more than two time-related data items displayed by the timepiece in both directions, but still with the idea of using a pusher to select the displayed data item and a stem to correct said data item, an alternative approach must be found to using the sliding pinion, this approach being that proposed by the present invention, which is characterized in that it includes a pusher for changing function, whose actuation moves a control wheel causing said wheel to mesh with a corrector pinion for the selected function, and a stem covered with a crown, whose rotation in one direction or the other causes said control wheel to pivot, which in turn drives one of said corrector pinions to correct said selected function data by adding or subtracting (in one direction or the opposite direction).
The features and advantages of the present invention will appear from the following description, given with reference to the annexed drawings, and providing, by way of explanatory, but non-limiting example, a preferred embodiment of the invention. In the drawings:
The general principle of the present invention is shown in
In a more elaborate version of the present invention and as shown in
Finally, in a preferred version of the invention,
Moreover, in the preferred version described in the paragraph above, the device of the invention is made so that when pusher 1 is actuated, simultaneously with the movement of control wheel arbour 19 in a circular trajectory, control wheel 2 rotates on itself and does not drive function corrector pinion (3, 4, 5, 6) with which it is made to mesh.
There will now be described in detail the composition of the device of the invention, embodied in the aforementioned preferred version and in the more elaborate version where stem 7 may be disposed in three different axial positions. With this aim, reference will mainly be made to
To make it possible for the second intermediate wheel 41 to engage either on main intermediate wheel 20, or on the last wheel set 46 controlled by stem 7, the second intermediate wheel 41 is mounted on an uncoupling arm 42 pivoting about the first arbour 17, on which the first and second assemblies rotate freely. Uncoupling arm 42 is controlled by a control lever 50 returned by a third spring 5, said lever 50 being controlled by the lever system 11 and 35 actuated by pusher 1.
In the particular case shown in the Figures, the number of teeth 30 of star 14 is not N but a number N+1, in order to provide an additional “rest” function in which control wheel 2 is not meshed with any of the corrector pinions. Thus in the case shown, star 14 is provided with five teeth 30 disposed at 72° with respect to each other, the corrector pinions being reduced to four, still arranged at 72° with respect to each other.
As can be seen in
As shown in
When stem 7 is driven in rotation, it drives a first intermediate wheel 43, which in turn drives a second intermediate wheel 44, which is meshed with an intermediate wheel set 45 actuating an bottom plate-plate 46 intermediate wheel, with wheel 46 meshing finally with second intermediate wheel 41. In this situation and if control wheel 2 is oriented towards the additional rest function in which said control wheel 2 is not meshed with any of the corrector pinions (a situation which is not shown here), jumper spring 22 locks star 14 and a rotational motion of stem 7 transmits this motion to control wheel 2, which turns idly.
The function change is achieved by a press on pusher 1 followed by a complete release of pressure. Various phases of this change will now be described with reference to
The important role played by second intermediate wheel 41 was explained above, said wheel 41 meshing, on the one hand, permanently like a planetary wheel with central wheel 24, and on the other hand, either with main intermediate wheel 20 when pusher 1 is actuated to perform a function change, or with the last wheel set 46 of the gear train ending with the stem to perform a correction of the selected function.
Since the direction of rotation 70 of control wheel 2 is opposite to the direction of rotation 60 of the star wheel, the primitive radii of the wheel sets forming the aforementioned kinematic chain need to be dimensioned so that the angular movement of control wheel 2 is such that it leaves immobile the corrector pinion (3, 4) which it leaves or with which it engages. Mathematical evolutions established two equations which, if satisfied, ensure the desired result, namely
It should be noted that the primitive radii of the corrector pinions (3 to 6) and the radii of the first and second intermediate wheels do not appear in these equations and can thus be chosen freely. Further, the table below gives a practical embodiment example:
As soon as pusher 1 is released, control wheel 2 is driven by the rotation of stem 7 which is capable of correcting (by adding or subtracting) the data displayed by the time function selected by pusher 1. This situation is the same as that shown in
The rotation of stem 7 drives gear train 47, 43, 44, 45, 46 the last wheel set of which, the bottom plate-plate intermediate wheel 46, meshes finally with central wheel 24 via second intermediate wheel 41. Central wheel 24 drives central pinion 18 which is coaxially connected thereto, said central pinion 18 in turn driving control wheel 2, which finally drives the new function corrector pinion 3 in one direction or the other, according on the direction of rotation imparted on crown 8 covering stem 7.
To conclude this description, it should be emphasised that the present invention is not limited to the particular embodiment of the preferred system described in detail above.
It would be possible, for example, to omit the second intermediate wheel 41 and consequently the first intermediate wheel 40, if the third assembly were formed of a main intermediate wheel 20, friction mounted on main intermediate pinion 21, pinion 21 meshing directly with star wheel 16 and wheel 20 meshing both with the second assembly, formed of central wheel 24 and central pinion 18, and with the gear train connected to stem 7, said train having a radial uncoupling means controlled by the pusher, during the actuation thereof.
In this derivative version, the rest of the mechanism remains the same as that mentioned with reference to the preferred version, the main idea of the present invention consisting in the fact that a function change pusher 1 moves a control wheel 2 and causes it to mesh with a corrector pinion for the selected function and that a stem 7, driven in rotation in one direction or the other, in turn drives the selected corrector pinion to correct, by adding or subtracting, the displayed data of said selected function.
Number | Date | Country | Kind |
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12181207.7 | Aug 2012 | EP | regional |