A leap-year display mechanism for a horological movement with a perpetual calendar display including a drive element connected to a month wheel set rotated by one step per month, a transmission star intended to be attached to a structure of the horological movement, arranged along the stroke of the drive element so as to be rotated thereby when the month wheel set completes one full revolution, a leap-year display connected to the transmission star via a reduction gear train so that with each revolution of the month wheel set, the leap-year display is rotated by one step.

The present invention provides a flip clock, in particular to a structure improvement of the digital perpetual calendar clock capable of reducing the quantity of the page sheets. The perpetual calendar clock includes a first digit rotational roller and a second digit rotational roller; the two rotational rollers are provided with a plurality of page sheets to display the digits of the tens place and the ones place respectively. Moreover, the perpetual calendar clock further includes a carrying shaft element, and the two rotational rollers are embedded into the two ends of the carrying shaft member respectively at the same shaft. When the second digit rotational roller rotates, a rotational teeth member on the carrying shaft member drives the first digit rotational roller to rotate. The present invention can reduce the power consumption by using less digit page sheets.

A magnetic indexing system (10) for a display (12) including a structural element (11) and a display (12) arranged movably relative to the structural element (11), a pair of magnetic elements (13, 14) having an anchoring portion (130, 140) by which a first magnetic element (13) is fastened to the structural element (11) and a second magnetic element (14) is fastened to the display (12), the magnetic elements being configured to cooperate with each other so as to generate a positioning torque of the display adapted to maintain the latter in a predetermined angular position with respect to the structural element (11), the magnetic elements including an interaction portion (131, 141) by which they are intended to face each other, the interaction portion of the first or second magnetic element having a cross-section reduced relative to that of its anchoring portion.