ISLAMIC HIJIRI CALENDAR

Abstract

The invention relates to an Islamic Hijiri calendar for a mechanical clockwork movement comprising a 30-position date indicator arranged to be driven by a date-driving mechanism and to engage with a large rocker (7). A month control mechanism is arranged to differentiate between the months with 29 days and those with 30 days. A year control mechanism is arranged to differentiate between an abundant year and a common year. During a common year, a large rocker (7) is arranged to engage with a date star (9), to move two teeth of the date star (9) in order to move from the 29th of a month to the 1 st of the following month, the large rocker (7) resting on the month cam (4).

Claims

1. An Islamic Hijiri calendar for a mechanical clockwork movement, comprising: a 30-position date indicator advancing by steps of one position to successively and cyclically display at the end of each day the numbers from 1 to 30, 1, 2... said date indicator being arranged to be driven by a date-driving mechanism and to engage with a large rocker; a month control mechanism arranged to differentiate between the months with 29 days and those with 30 days, the month control mechanism comprising a month star engaging with a month cam comprising twelve positions; and a year control mechanism arranged to differentiate between an abundant year and a common year, the year control mechanism comprising a year sector arranged to cause a one-step skip by a year star coupled to a year cam comprising flattened teeth and having a resting surface on each flattened tooth on which a finger rests in each plentiful year, the finger resting on a hollow portion between two flattened teeth to indicate a common year wherein the large rocker is arranged to engage during a common year with a date star, to pass two teeth of the date star from the 29th to the 1st of the next month, the large rocker resting on the month cam.

2. The calendar according to claim 1, wherein, in an abundant year, the large rocker is arranged to engage with the finger so as to cause the date star to skip a tooth to pass from the 30th to the 1st of the month.

3. The calendar according to claim 1, wherein the year cam (6) has eleven irregularly distributed flattened teeth.

4. The calendar according to claim 1, wherein the finger is pivotally mounted about an axis and comprising at one end a spout arranged to receive a tip of the large rocker in each abundant year.

5. The calendar according to claim 1, wherein a year sector is arranged to skip a year star by one step per year, according to a 30-year cycle.

6. The calendar according to claim 1, wherein a rocker is arranged to engage with a toothing pivoting on the axis of the date star to move a pad from a first position where it indicates a 29-day month to a second position where it indicates a 30-day month, said rocker resting on the month cam.

7. The calendar according to claim 6, wherein the pad, by means of two distinct indications, is arranged to indicate, through an opening in a dial, whether the month has a duration of 29 days or 30 days.

8. A timepiece comprising an Islamic Hijiri calendar according to claim 1.

9. A timepiece according to claim 8 in the form of a wristwatch.

Description

[0014] The features of the invention will become clearer upon reading the description of several embodiments given only by way of example, which is in no way limiting with reference to the schematic figures, in which:

[0015] FIG. 1 shows a top view of an Islamic Hijiri calendar mechanism during a common year;

[0016] FIG. 2 shows a top view of an Islamic Hijiri calendar mechanism during an abundant year;

[0017] FIG. 3 shows a part of a watch movement comprising an Islamic Hijiri calendar mechanism according to the present invention;

[0018] FIG. 4 shows a top view of a mechanism indicating on a watch face the presence of a month with a duration of 29 days;

[0019] FIG. 5 shows a top view of a mechanism indicating on a watch face the presence of a month with a duration of 30 days; and

[0020] FIG. 6 shows a top view of a mechanism indicating the presence of a 30-day month during the last month of the year.

[0021] As shown in FIG. 1, an Islamic Hijiri calendar for a mechanical clockwork movement comprises a 30-position date indicator advancing by steps of one position to successively and cyclically display at the end of each day the numbers from 1 to 30, 1, 2... said date indicator being arranged to be driven by a date-driving mechanism and to engage with a large rocker 7. The calendar further comprises a month control mechanism 1, 4 arranged to differentiate between the months with 29 days and those with 30 days, the month control mechanism comprising a month star 1 engaging with a month cam 4 comprising twelve positions. The calendar further comprises a year control mechanism arranged to differentiate between an abundant year and a common year, the year control mechanism comprising a year sector 10 arranged to cause a one-step skip by a year star 5 coupled to a year cam 6 comprising flattened teeth 12 and having a resting surface 13 (see FIG. 2) on each flattened tooth 12 on which a finger 8 rests in each plentiful year, the finger 8 resting on a hollow portion 14 between two flattened teeth 12 to indicate a common year.

[0022] During a common year, the large rocker 7 is arranged to engage with a date star 9, to move two teeth of the date star 9 in order to move from the 29th to the 1st of the following month, the large rocker 7 resting on the month cam 4.

[0023] In this example, the month star 1, thanks to intermediate wheels 2, 3, positions the month cam 4. A year sector 10 causes the year star 5 to skip one step per year on a thirty-year cycle. At the 12th month of the common year, the finger 8 is positioned, in the low position, in the recess of the year cam 6 out of the field of action of the tip 7a of the large rocker 7. The large rocker 7 makes two teeth of the date star 9 pass, to go from the 29th to the 1st of the next month.

[0024] The date star 9 has twenty-nine flattened teeth 17 and one pointed tooth 18 indicating the passage to a new cycle of days in a month.

[0025] As shown in FIG. 2, in an abundant year, the large rocker 7 is arranged to engage with the finger 8 so as to cause the date star 9 to skip a tooth to pass from the 30th to the 1st of the month.

[0026] The position of the month cam 4 indicates that the year is abundant. In this configuration, the finger 8 is located on the top of the year cam 6. The large rocker 7 is no longer resting against the month cam 4, but rather on the finger 8, causing the date star 9 to skip a tooth, in order to pass from the 30th to the 1st of the following month.

[0027] In each of these examples, the year cam 6 has eleven irregularly distributed flattened teeth 12.

[0028] The finger 8 is pivotally mounted around an axis 15 and has at one end a spout 16 arranged to receive a tip 7b of the large rocker 7 in each abundant year.

[0029] As shown in FIG. 4, a rocker 19 senses the month cam 4 to determine whether the current month is a 29-day or 30-day month based on the twelve positions shown on said month cam.

[0030] For this purpose, a pad 20, thanks to two distinct indications, here two different colors, indicates to the wearer, through an opening 21 of the date window 22 if the month has a duration of 29 days or 30 days.

[0031] The rocker 19 is arranged to engage with a toothing of the pad 20 which pivots on the axis of the date star 9 and allows the display of the 29/30 indication through the date window. The rocker 19 moves the pad 20 from a first position where it indicates a month with a duration of 29 days to a second position where it indicates a month with a duration of 30 days, the rocker 19 being supported by the month cam 4.

[0032] In this example, the pad 20 is positioned to indicate a month with a duration of 29 days.

[0033] In the example shown in FIG. 5, the rocker 19 senses the month cam 4 positioned to determine that the current month is a 30-day month.

[0034] Thus, the pad 20 is positioned to indicate to the wearer, through the opening 21 of the date window 22, that the current month is a 30-day month.

[0035] In the example shown in FIG. 6, during the last month of the year, it is the finger 8 that positions the rocker 19 to indicate a 30-day month.

[0036] In an abundant year, the finger 8 is located on the top of the year cam 6. The rocker 19 is no longer resting on the month cam 4, but rather on the finger 8, and allows the 30-day month to be displayed through the date window.

[0037] Such a calendar can be incorporated into a timepiece, such as a wristwatch or a clock.