A horology calendar system (100; 200) comprising: a date display member (10) including an opening (10a); and a month display member (30) arranged in such a way as to display an indication of the month in the opening (10a), notably when the opening (10a) is visible to a user of the calendar system and/or when the calendar system is indicating the first day of a given month.

An indicator device for watchmaking has a drive toothed wheel which rotates a driven programme wheel is substantially a circular crown with an external toothing and an internal toothing. The latter meshes with an eccentric internal toothed wheel whose cycloidal rotary movement with a suitable transmission ratio allows the information given on the programme wheel to be indicated. The device is suitable for making perpetual calendars of the clocks.

A display mechanism including a mechanism for fast correction of a position of a display wheel set, an intermediate wheel set ensuring synchronization with an automatic drive mechanism, and, inserted between the intermediate wheel set and the display wheel set, a safety lever driven by the display wheel set during periodic driving thereof, in a trajectory that interferes with a spatial volume of the intermediate wheel set, such that, when the intermediate wheel set is correctly synchronized, the trajectory of the lever does not interfere with the intermediate wheel set, and, when the intermediate wheel set is not correctly synchronized, the trajectory of the safety lever interferes with the intermediate wheel set, which the safety lever then drives in an opposite direction to a single direction of normal operation, to resynchronize the intermediate wheel set.

In an annual or perpetual calendar mechanism, a day-of-the-month wheel includes a notch. At each actuation of a lever, a first pawl finger effects an actuation of one step, on one of the teeth of the day-of-the-month wheel. Upon actuation of the lever at the end of a month of fewer than 31 days, a second pawl finger effects, in the notch, an actuation of the day-of-the-month wheel by a whole number of steps. The notch is positioned between two consecutive teeth among the teeth of the day-of-the-month wheel. The day-of-the-month wheel has a peripheral edge which forms the profiles of its teeth as well as the notch.

A horology calendar system (100; 200) comprising: a date display member (10) including an opening (10a); and a month display member (30) arranged in such a way as to display an indication of the month in the opening (10a), notably when the opening (10a) is visible to a user of the calendar system and/or when the calendar system is indicating the first day of a given month.

A horology calendar system (200) comprising:a date wheel (1);a month cam (300); anda kinematic connection element (8) arranged such that the date wheel allows the driving of the motion of the month cam.

A display mechanism including a mechanism for fast correction of a position of a display wheel set, an intermediate wheel set ensuring synchronization with an automatic drive mechanism, and, inserted between the intermediate wheel set and the display wheel set, a safety lever driven by the display wheel set during periodic driving thereof, in a trajectory that interferes with a spatial volume of the intermediate wheel set, such that, when the intermediate wheel set is correctly synchronized, the trajectory of the lever does not interfere with the intermediate wheel set, and, when the intermediate wheel set is not correctly synchronized, the trajectory of the safety lever interferes with the intermediate wheel set, which the safety lever then drives in an opposite direction to a single direction of normal operation, to resynchronize the intermediate wheel set.

A calendar mobile (10) indicating time information or information derived from the time, comprising at least one first obstacle element (1a, 2a, 3a) intended to receive a driving contact action driving the calendar mobile and/or intended to transmit a driving contact action from the calendar mobile, the first obstacle element being made of titanium or of titanium alloy, the mobile being a disk or the mobile having substantially the shape of a disk or the mobile having substantially the shape of a disk ring.