US3537255A

US3537255A - Day-date watch

Info

Publication number: US3537255A
Application number: US781904A
Authority: US
Inventors: Jean-Claude Schneider
Original assignee: Tissot SA
Current assignee: Tissot SA
Priority date: 1967-12-22
Filing date: 1968-12-06
Publication date: 1970-11-03
Anticipated expiration: 1987-11-03
Also published as: CH512097A; DE1810125B2; GB1248790A; CH1812867A4; FR1587255A; DE1810125C3; DE1810125A1

Description

NOV. 19,70 JEAN-CLAUDE SCHNEIDER v3,537,255

DAY-DATE WATCH Filed Dec. 6, 1968 United States Patent 3,537,255 DAY-DATE WATCH Jean-Claude Schneider, Plaisance, Switzerland, assignor to Ch. Tissot 8: Cie, Le Locle, Switzerland Filed Dec. 6, 1968, Ser. No. 781,904 Claims priority, application Switzerland, Dec. 22, 1967, 18,128/67 Int. Cl. G04b 19/24 US. C]. 58-58 5 Claims ABSTRACT OF THE DISCLOSURE There are known various timepieces which not only give the date but also the day of the week in two corresponding openings made through the dial.

In order to improve the ease of reading and the aesthetic appearance, recent constructions make these indications appear side by side in the same generally rectangularly shaped window or at least in two juxtaposed windows separated by a separation which is as narrow as possible.

The indications of the day and the date are carried by dilterent coplanar members which generally are each equipped with a jump-spring device ensuring the passage from one indication to the next by an abrupt jump in order to avoid the simultaneous though partial appearance of two indications in the window of the dial. There are known solutions where the driving device for the indicating members is a single one which drives only one of the members, the driving of the second taking place through the first. This solution which, simpler from the point of view of the driving, becomes more complicated in the design of an adjustment device for the two mobiles since it is necessary to adjust one independently of the other. This date setting operation generally takes place in known manner by giving to the hour hand by means of the setting button a reciprocating movement on either side of the point where the date is changed. To avoid that by this operation the change takes place on the two members simultaneously which would be contrary to the goal sought the driving of one of the two must take place by means of a pawl device which makes it move in only one direction.

The obtention of such arrangements is thus fairly complicated and in any event causes considerable loss of energy through friction.

The present invention has for its purpose a watch with a day-date indicating means, these two indications appearing in at least one window in the dial and which paliates these drawbacks.

This timepiece is characterized by the fact that these two indications are carried on two tangential but not coaxial hypocyclic rings, the inner ring driving by its outer teeth the inner teeth of the outer ring, with a single driving mechanism and a single jump mechanism causing the simultaneous movement and the positioning of the two rings.

The accompanying drawing represents by way of example one embodiment of the present invention.

FIG. 1 is a plane view of the device while FIG. 2 is a partial cross sectional view which is perpendicular to the plane of the indicating members.

In these two figures 1 refers to the plate of the movement on which the two indicating members slide while bearing on shoulders provided for this purpose. The member which indicates the days of the week has the shape of a ring 2 which carries indications 21 and includes outer teeth 22 and inner teeth 24. Its rotational axis passes through point 23 which differs from the main axis of movement 3-3.

The outer rolling circle of this ring is tangent at point 25 with the inner rolling circle of the ring carrying the date indications.

The same is also a ring 3 whose axis of rotation passes this time through point 33 which coincides with the main axis of the movement. The ring 3 carries the date indications at 31 and includes inner teeth 32 meshing along a certain distance on either side of point 25 with the corresponding teeth 22 of ring 2 and thus positioning it relative thereto. Its position in the plane is ensured on the one hand by its taking support at point 25 and on the other hand by three

spring wires

41, 42, 43 supporting it relative to plate 1 and bearing tangentially against the bottom of a groove 34 on its periphery. The two

springs

42 and 43 make it possible for ring 3 to slide to the right parallel to their axis if it is subjected to a force exerted against spring 41. Ring 3 comprises a second inner toothing 36 carried by ring 35 applied itself against ring 3.

The driving device is constituted by a cam 51 whose rotational axis is at 52, and actuating lever 53 pivoted at 54 and which has a fixed roller 55 sliding around the outer periphery of the cam. Lever 53 moves against the urging of spring 59 which progressively stores the energy necessary for the abrupt movements of the indicating members. Lever 53 itself actuates a spring lever 56 also pivoted at axis 54 and which has a curved narrowed part 57 terminating into a rounded pusher 58. The judicious shape given to cam 51 gives once a day an abrupt movement to lever 53 and to lever 56, the length of this movement corresponding to a step in teeth 24. The return movement takes place slowly during 24 hours without a reverse driving of teeth 24 taking place owing to the judicious shape of the teeth and of spring lever 56.

The jumper device is constituted by a U-shaped spring 61 bearing on the one hand against a fixed washer 62 and on the other hand against a roller 63 whose support between two teeth of teeth 24 retains in place ring 2.

Once every 24 hours the driving device thus leads ring 2 to turn of a turn. By meshing teeth 22 on teeth 32 the disc 3 undergoes a movement of equivalent length. But owing to the difference in diameter of the two rolling circles, this movement corresponds to Vs of a turn of disc 3. When the date changes, disc 3 will thus advance by two divisions, whence the necessity of inscribing the same not in the simple numerical order but in the following order:

1-17-218-319 etc. 14-30-15-31-16 There results from the previously described construction that disc 2 makes one turn in two weeks, while disc 3 makes two turns in a month. It also results that the respective diameter of their rolling circles must be selected in the ratio of 28/31.

To set the date two procedures must be followed:

If it is desired-to change the indication of the day, for example when the watch is first started or after it has been stopped for a while, there is resorted to the known method which consists in giving a reciprocating movement to the hour hand by means of the button on either side of the position which corresponds to midnight. Upon each of these movements, ring 2 which indicates the day will advance by one notch. It will also drive in its advance the date ring 3 which will have advanced by as many units as the ring indicating the days will have made movements.

The second procedure is concerned with the adjustment of the ring which indicates the date alone, during initial adjustment of the watch or when going from one month to the other when the elapsed month has less than 31 days. The winding stem is then pulled into a third position which has for eifeet simultaneously to mesh a pinion fast on the winding stern into teeth 36 of ring 35 fast on ring 3 and to free teeth 32 from 22 by moving ring 3 against spring 41. When the desired date appears in the window of the dial it sufiices to repush the winding stern back into place and ring 3 will resume its normal position under the urging of spring 41. a

What is claimed is: p 1.;In a day-date indicating timepiece, an inner ring and an outer ring carrying said indications, one of said rings carrying the date indication'and the other of said rings carrying the day' of the week indication, said rings be ing hypocyclically tangent but non coaxial, the inner ring having outer teeth driving the inner teeth of said outer ring, and a single driving device and a single jumper mechanism in contact with said rings to simultaneously move them and position them.

2. Timepiece according to claim 1, wherein said rings have a rolling ratio of 28/ 31;

3. Device according to claim 1, having springs urging against said outer ring in such a way as to free the teeth thereof outside of said'inner ring and to adjust it to a desired date independent of said inner ring.

4. Timepiece according to claim 1, wherein said inner ring comprises two consecutive series of the seven days of the week and moves by of a turn each day.

5. Timepiece according to claim 1, wherein said outer ring moves by A of a turn each day and that the dates thereon are inscribed in the following order:

1-17218-319 etc. 143l)153116 References Cited G. H. MILLER, JR., Assistant Examiner STEPHEN J. TOMSKY, Primary Examiner