CH653841GA3 - Clockwork movement provided with a perpetual calendar mechanism - Google Patents

Abstract

It comprises a motive train propelled by a barrel, driving a cannon-pinion which drives, by way of a minute train, an hour wheel. This hour wheel drives a wheel (7) making one revolution in twenty-four hours driving, by a finger (8), a tooth of a calendar wheel (9) once every twenty-four hours. The calendar wheel (9) carries a calendar indication hand (31) cooperating with a graduation on the dial and is linked to a rack (11) of a lever (12). The calendar wheel (9), held in angular position by a pawl (15), carries a catch (25) cooperating with one of the lands of a rake (20) of a lever (18) articulated on the free end of the pawl (15). This lever (18) includes a first boss (22) cooperating with a month cam (21) driven in rotation, at a rate of one revolution per year with the aid of a finger (34) articulated on the lever (12) carrying the rack (11) and a second boss (24) cooperating with a secular cam (23) driven in rotation by the month cam (21) by way of a pinner (39) at a rate of one revolution in one hundred years. <IMAGE>

Description

** ATTENTION ** start of the DESC field may contain end of CLMS **.

CLAIMS 1. Clock movement fitted with a retrograde perpetual calendar mechanism, comprising a driving train driven by a barrel, driving a carriageway which itself drives, by means of a clockwork train, an hour wheel, characterized by the fact that the hour wheel (5) drives a wheel (7) making a revolution in twenty-four hours carrying a finger (8) driving once every twenty-four hours a tooth of a date wheel (9 ): by the fact that the date wheel (9) carries a pinion (10) carrying a date indication needle (31) cooperating with a graduation occupying a sector of a circle on the dial of the movement, this pinion (10) being engaged with a rack (11) of a lever (12), pivoted on a base plate (14), and subjected to the action of a return spring (12 '); by the fact that the date wheel (9) is held in angular position by a pawl (15) and that this wheel carries an index (25) whose tip cooperates with one of the steps of a rake (20) a lever (18) articulated on the free end of the pawl (15); by the fact that the lever (18) comprises a first boss (22) cooperating with a month cam (21) driven in rotation, at the rate of one revolution per year using a finger (34) articulated on the lever (12) carrying the rack (ll); and by the fact that the lever (18) has a second boss (24) cooperating with a secular cam (23) rotated by the month cam (21) by means of a mobile (39) at a rate of 'a turn in a hundred years.

2. Movement according to claim 1, characterized in that it also comprises a lever (26) pivoted on the base plate (14), and subjected to the action of a spring (28) tending to apply, except during the rotation of the date wheel (9), the lever (18) against the month cam (21) or the secular cam (23).

3. Movement according to claim 1 or claim 2, characterized in that the month cam (21) comprises lifts (32) whose distance from the center corresponds to the duration of thirty or thirty-one days in March to January; by the fact that it comprises a four-pointed satellite (33) indexed once a year by a fixed finger (35), one of the points of which, corresponding to the month of February of twenty-nine days is longer than the three other spikes; by the fact that the points of the satellite (33) cooperate with the boss (22) of the lever (18) to determine the indication of the duration of the month of February at twenty-eight respectively twenty-nine days; by the fact that the secular cam (23) comprises a satellite (37) with four points, one of which is longer than the other three, indexed once every hundred years by a fixed finger (41), and by the fact that when the long tip of the satellite (37) is in the service position, the duration of the month of February is determined by the position of the lever (18) whose boss (24) comes into contact with said long tip of the satellite (37).

4. Movement according to claim 3, characterized in that the mobile (39) comprises a wheel with twenty teeth cooperating with two teeth (38) of the month cam (21), this mobile having on the other hand two teeth ( 40) cooperating with the twenty teeth of the secular cam (23) so that the latter is rotated every ten years by ȯ of a turn on February 1 and of ȯ of a turn on March 1.

5. Movement according to claim 3, characterized in that the mobile (39) comprises a wheel with twenty teeth cooperating with two teeth of the month cam (21), this mobile further comprising a tooth cooperating with the ten teeth of the secular cam (23) so that the latter is rotated every ten years by 1/20 of a turn on February 1 and by ȯ of a turn on March 1.

6. Movement according to one of the preceding claims tes, characterized in that the month cam (21) had the secular cam (23) are pivoted coaxially on the same axis.

The mechanisms of retrograde perpetual calendar are relatively well known; The date hand of such a mechanism indicates the number of the day on an arc drawn on the dial, and not on a complete circle. In this way, it is necessary that when the needle arrives on the last day of the month.

 28 29, 30 or 3 day, it instantly demotes to its starting point on the number 1.

In this kind of mechanism, the indications of days and months are not retrograde.

Existing devices of this type are not secular, since they are unable to make common three out of four secular years as the Gregorian calendar requires.

The purpose of the present invention is to provide a secular date mechanism, that is to say one which avoids the error of three days out of four hundred years made by current devices.

The timepiece movement provided with a retrograde perpetual calendar mechanism according to the invention is distinguished by the characteristics listed in claim 1.

The accompanying drawing illustrates schematically and by way of example an embodiment of the perpetual calendar mechanism according to the invention.

Figure 1 illustrates this mechanism in plan at the position of May 1.

Figure 2 illustrates this mechanism in plan at the position of May 31 at midnight.

Figure 3 illustrates this mechanism in plan at the position of February 28 of a secular year.

Figure 4 is a sectional view of the mechanism.

Figures 5 to 8 are diagrams illustrating in detail the operation of the cam of the centuries.

The movement illustrated very partially only as regards its parts which do not constitute the perpetual calendar mechanism, comprises a completely conventional driving part comprising a barrel 1 (FIG. 4) driving a wheel in the center 2 which carries a floor 3. This carriageway 3 drives an hour wheel 5 by a timer 4. This hour wheel 5 carries a pinion 6 which drives a wheel 7 at the rate of one complete revolution per twenty-four hours. The wheel 7 is integral with a finger 8 which drives once every twenty-four hours, around midnight, a tooth of a date wheel 9 in the direction of the arrow A.

This date wheel carries a pinion 10 meshing with the rack 11 of a lever 12 pivoted at 13 on a base plate 14. A spring 12 'acts on the lever 12 and tends to move it in the direction of arrow B, which tends to rotate the date wheel 9 in the direction of the arrow C.

For this reason, the date wheel 9 is provided with a retaining pawl 15, pivoted at 16 and subjected to the pressure of the spring 17. A lever 18 is pivoted at 19 on the free end of the retaining pawl. Approximately in the middle of its length, it has the shape of a rake or staircase 20 with four notches. This lever 18 and therefore its rake 20 is positioned by a month cam 21 acting on a boss 22 of said lever and a centuries-old cam 23 acting on a boss 24 of this lever 18.

The cam for months 21 differs from the non-retrograde perpetual calendar mechanisms in that its deepest rungs correspond to the 31-day months and not to the 28-day months.

The cam of the 23 centuries only carries a functional level, that of February 28 of the secular years. In all other cases, it is the month cam 21 which controls the lever.

The date wheel 9 carries an index 25 whose tip

acting against one of the notches of the rake 20 of the lever 18 raises the pawl 15 and releases the wheel 9. This function always occurs when passing from the last day of the month to the next.

Finally, holding the lever 18 against the cam for months 21 or centuries 23 is achieved by pressing the arm 26, pivoted at 27 and subjected to the action of the spring 28, against a pin 29 carried by said lever 18.

Under the push of the finger 8 secured to the twenty-four hour wheel 7, the date wheel 9 advances by one tooth every twenty-four hours in the direction of the arrow A. A pin 30, carried by this wheel 9 , releases after the first day of the month the lever 26 which under the pressure of the spring 28 bears against the pin 29 and positively positions the lever 18 in abutment against the corresponding steps of the cams 21 and 23. Here the position of the lever 18 is given by the entry into contact of its boss 22 with the May rung of the month cam 21, a deep rung (Figure 2).

For the duration of May, the wheel 9 advances one tooth each day. On the 3rd day, the tip of the index finger 25 arrives in front of the outermost notch of the rake 20 of the lever 18. In FIG. 2, it can be seen that when the needle of the date 31 passes from May 31 to On June 1, the lever 18 is driven by the index finger 25 in the direction of the arrow D, which has the effect of lifting the tooth of the pawl 15 and of releasing the wheel 9 which will suddenly shift down under the action of the rack and its spring 12 ′, this when the finger 8 has finished driving the tooth of the wheel 9.

The drive of the lever arm 18 by the index finger 25 also has the effect of forcing the pin 29 to move and engage in the notch of the lever 26, which has the effect of keeping the pawl 15 in its position clear of the toothing of the wheel 9. This necessary function allows the wheel 9 to downshift until the end, needle 31 on the number 1, avoiding the risk of an early stop of this movement. The release of the pin 29 from the notch of the lever 26 is caused by the pressing of the pin 30 on the beak of the lever 26 after the first day of the following month.

We studied the case of a 31-day month. For the months of 30.29 or 28 days, the operation is similar, except for the position of the lever arm 18 which is raised more or less by the cams 21 or 23. This has the effect of bringing the moment of contact between the 'index 25 and one of the steps of the rake 20 and thus give the months the desired length.

It remains to be seen how the cam of months 21 and that of centuries 23 works.

The cam for the months 21 is integral with a star with twelve branches 31 and comprises lifts 32 whose distance to the center depends on the number of days, thirty or thirty-one, from March to January. This cam also includes a satellite 33 pivoted on the star 31.

The star 31 is driven at the rate of one step per month by a finger 34 driven by the lever 12. The satellite, cooperating with a fixed finger 35 performs a revolution on itself in four years. The height of the points of this satellite having the shape of a four-pointed star, determines the duration, twenty-nine or twenty-eight days of the month of February.

The finger 34 is articulated on the lever 12 so as not to influence the position of the star 31 during the retraction of the rack 11. The star 31 is positioned by a jumper 36.

As the cam 21 does not determine by its lifts 32 and the tips of the satellite 33 that the length of the months (leap or not). a system is necessary which prevents, in centuries not multiple of 400, the lever 18 from falling in February on the tip of the satellite 33 determining the months of 29 days. To achieve this, we use the second cam 23 which turns around in a hundred years. This mobile carries a satellite 37 which, for its part, turns around in 400 years. Three of the four points of this satellite 37 are higher and come, during the months of February of the 3 secular years (February of 28 days) to prevent the lever 18 from moving to the leap year position (see FIG. 3).

The satellite 37 of the cam 23 must in no case influence the duration of the month preceding and following the month of February. For this, he must get into working position on February 1 and leave this position on March 1 of years ending in ... .00, and this in the form of a jerky movement.

To achieve this result, the system works as follows; The star 31 makes l / l2 of turn per month, that is to say one turn per year. On this mobile, a Maltese cross type drive is fixed. For a division of twelve steps, only two teeth 38 are left corresponding to the months of February and March. These two teeth will drive each year by two steps a wheel of twenty teeth 39. This wheel 39 will therefore turn one step on February 1st and another on March 1st of each year. The other ten months of the year, it will remain stationary. So it will do a tour in ten years. The wheel 39 carries two teeth or drive pins 40 on twenty steps. These two teeth 40 are positioned so that every tens of years they drive the cam 23 with a step on the 1st of February and with a step on the 1st of March. The cam 23 carries twenty teeth and will therefore go around in a hundred years. This cam 23 carries a satellite 37 driven by a fixed finger 41 of a quarter turn by turn of the cam 23. This satellite is positioned so that only in years. .90, on February 1, satellite 37 arrives at the position shown in Figure 5. March 1 of the years. .90, the satellite 37 will be positioned according to FIG. 7 and the teeth 40 will be in position 1. During the following ten years, the teeth 40 will rotate in jerks, without influencing the position of the cam 23, to arrive in position 2 on 1st of March . .99, position that he will keep until January 31. .00. During all this time, the satellite 37 has no influence on the boss 24 of the lever 18.

February 1 of the years. .00, the teeth 40 drive the cam 23 as shown in FIG. 7 and one of the four points of the satellite 37 arrives in front of the boss 24 of the lever 18. During secular years whose month of February is normally a leap, (2000; 2400 ; ...), it is the shortest point of the satellite 37 which is in front of the boss 24 of the lever 18 which is therefore free and it is the boss 22 which will position the lever 18 on the leap rung (the long point of satellite 33) of cam 21.

In the years ending with. .00 of the three centuries following a century multiple of 400, these are the three upper parts of satellite 37 which are successively positioned. The boss 24 is supported on the satellite 37 and therefore prevents the boss 22 from bearing on the cam 21. These three centuries will therefore have normal February (28 days). This position is shown in Figure 3.

On March 1, leap centuries or not, satellite 37 takes the position illustrated in Figure 8 and becomes inactive for one hundred years. The cam 23 is positioned by a jumper 42.

The version that we have just described comprises two pivot axes for the cams 21 and 23. Another arrangement of these two cams consists in superimposing them on the same axis. At this time, the lever 18 has only one boss which works on two planes.

In a variant, the secular cam 23 may have only ten teeth cooperating with a tooth of the mobile 39.

This secular cam 23 is then rotated every ten years by half-steps, 1/20 of a turn on February 1 and de of a turn on March 1.

Claims (6)

1. Clock movement fitted with a retrograde perpetual calendar mechanism, comprising a driving train driven by a barrel, driving a carriageway which itself drives, by means of a clockwork train, an hour wheel, characterized by the fact that the hour wheel (5) drives a wheel (7) making a revolution in twenty-four hours carrying a finger (8) driving once every twenty-four hours a tooth of a date wheel (9 ): by the fact that the date wheel (9) carries a pinion (10) carrying a date indication needle (31) cooperating with a graduation occupying a sector of a circle on the dial of the movement, this pinion (10) being engaged with a rack (11) of a lever (12), pivoted on a base plate (14), and subjected to the action of a return spring (12 '); by the fact that the date wheel (9) is held in angular position by a pawl (15) and that this wheel carries an index (25) whose tip cooperates with one of the steps of a rake (20) a lever (18) articulated on the free end of the pawl (15); by the fact that the lever (18) comprises a first boss (22) cooperating with a month cam (21) driven in rotation, at the rate of one revolution per year using a finger (34) articulated on the lever (12) carrying the rack (ll); and by the fact that the lever (18) has a second boss (24) cooperating with a secular cam (23) rotated by the month cam (21) by means of a mobile (39) at a rate of 'a turn in a hundred years. 2. Movement according to claim 1, characterized in that it also comprises a lever (26) pivoted on the base plate (14), and subjected to the action of a spring (28) tending to apply, except during the rotation of the date wheel (9), the lever (18) against the month cam (21) or the secular cam (23). 3. Movement according to claim 1 or claim 2, characterized in that the month cam (21) comprises lifts (32) whose distance from the center corresponds to the duration of thirty or thirty-one days in March to January; by the fact that it comprises a four-pointed satellite (33) indexed once a year by a fixed finger (35), one of the points of which, corresponding to the month of February of twenty-nine days is longer than the three other spikes; by the fact that the points of the satellite (33) cooperate with the boss (22) of the lever (18) to determine the indication of the duration of the month of February at twenty-eight respectively twenty-nine days; by the fact that the secular cam (23) comprises a satellite (37) with four points, one of which is longer than the other three, indexed once every hundred years by a fixed finger (41), and by the fact that when the long tip of the satellite (37) is in the service position, the duration of the month of February is determined by the position of the lever (18) whose boss (24) comes into contact with said long tip of the satellite (37). 4. Movement according to claim 3, characterized in that the mobile (39) comprises a wheel with twenty teeth cooperating with two teeth (38) of the month cam (21), this mobile having on the other hand two teeth ( 40) cooperating with the twenty teeth of the secular cam (23) so that the latter is rotated every ten years by ȯ of a turn on February 1 and of ȯ of a turn on March 1. 5. Movement according to claim 3, characterized in that the mobile (39) comprises a wheel with twenty teeth cooperating with two teeth of the month cam (21), this mobile further comprising a tooth cooperating with the ten teeth of the secular cam (23) so that the latter is rotated every ten years by 1/20 of a turn on February 1 and by ȯ of a turn on March 1. 6. Movement according to one of the preceding claims tes, characterized in that the month cam (21) had the secular cam (23) are pivoted coaxially on the same axis. The mechanisms of retrograde perpetual calendar are relatively well known; The date hand of such a mechanism indicates the number of the day on an arc drawn on the dial, and not on a complete circle. In this way, it is necessary that when the needle arrives on the last day of the month.  28 29, 30 or 3 day, it instantly demotes to its starting point on the number 1. In this kind of mechanism, the indications of days and months are not retrograde. Existing devices of this type are not secular, since they are unable to make common three out of four secular years as the Gregorian calendar requires. The purpose of the present invention is to provide a secular date mechanism, that is to say one which avoids the error of three days out of four hundred years made by current devices. The timepiece movement provided with a retrograde perpetual calendar mechanism according to the invention is distinguished by the characteristics listed in claim 1. The accompanying drawing illustrates schematically and by way of example an embodiment of the perpetual calendar mechanism according to the invention. Figure 1 illustrates this mechanism in plan at the position of May 1. Figure 2 illustrates this mechanism in plan at the position of May 31 at midnight. Figure 3 illustrates this mechanism in plan at the position of February 28 of a secular year. Figure 4 is a sectional view of the mechanism. Figures 5 to 8 are diagrams illustrating in detail the operation of the cam of the centuries. The movement illustrated very partially only as regards its parts which do not constitute the perpetual calendar mechanism, comprises a completely conventional driving part comprising a barrel 1 (FIG. 4) driving a wheel in the center 2 which carries a floor 3. This carriageway 3 drives an hour wheel 5 by a timer 4. This hour wheel 5 carries a pinion 6 which drives a wheel 7 at the rate of one complete revolution per twenty-four hours. The wheel 7 is integral with a finger 8 which drives once every twenty-four hours, around midnight, a tooth of a date wheel 9 in the direction of the arrow A. This date wheel carries a pinion 10 meshing with the rack 11 of a lever 12 pivoted at 13 on a base plate 14. A spring 12 'acts on the lever 12 and tends to move it in the direction of arrow B, which tends to rotate the date wheel 9 in the direction of the arrow C. For this reason, the date wheel 9 is provided with a retaining pawl 15, pivoted at 16 and subjected to the pressure of the spring 17. A lever 18 is pivoted at 19 on the free end of the retaining pawl. Approximately in the middle of its length, it has the shape of a rake or staircase 20 with four notches. This lever 18 and therefore its rake 20 is positioned by a month cam 21 acting on a boss 22 of said lever and a centuries-old cam 23 acting on a boss 24 of this lever 18. The cam for months 21 differs from the non-retrograde perpetual calendar mechanisms in that its deepest rungs correspond to the 31-day months and not to the 28-day months. The cam of the 23 centuries only carries a functional level, that of February 28 of the secular years. In all other cases, it is the month cam 21 which controls the lever. ** ATTENTION ** end of the CLMS field may contain start of DESC **.