A disengageable winding device (1) for a barrel (2) provided with a spring, comprising a ratchet (3) mounted on a winding arbor such that it is rigidly connected thereto, the winding arbor being an arbor for winding the barrel (2), the rotation of which winds up the barrel (2), and a winding gear train (40) meshing with the ratchet (3), the rotation of the winding gear train (40) driving the rotation of the ratchet (3) and that of the winding arbor.

Transmission device (100), for example for a watch mechanism (110), in particular for a winding train (100, 201) of a watch movement (120), including an input element (6) intended to be driven only in a first direction, an output element, a first mechanical connection arranged such that the displacement of the input element in a first direction causes the displacement of the output element in a second direction, and a second mechanical connection (9, 9) arranged such that the displacement of the input element in the first direction causes the displacement of the output element in a third direction, the third direction being opposite the second direction.

Transmission device (100), for example for a watch mechanism (110), in particular for a winding train (100, 201) of a watch movement (120), including an input element (6) intended to be driven only in a first direction, an output element, a first mechanical connection arranged such that the displacement of the input element in a first direction causes the displacement of the output element in a second direction, and a second mechanical connection (9, 9) arranged such that the displacement of the input element in the first direction causes the displacement of the output element in a third direction, the third direction being opposite the second direction.

A barrel (1) for self-winding timepiece including a drum (11) provided with an inner lateral wall (12) and a mainspring (2) forming a winding including an outer coil (21) the end (22) of which is friction coupled with the inner lateral wall and free to slip against the inner lateral wall in the event of overtension of the mainspring (2). The end of the outer coil includes an external face (23) having two friction surfaces (24, 25) disposed in the top and bottom portion of the outer coil and arranged to be in contact with the inner lateral wall in such a way that the portion between the friction surfaces, referred to as central portion (26), is not in contact with the inner lateral wall, the central portion forming a reservoir (27) for a lubricant between the two friction surfaces.

A barrel (1) for self-winding timepiece including a drum (11) provided with an inner lateral wall (12) and a mainspring (2) forming a winding including an outer coil (21) the end (22) of which is friction coupled with the inner lateral wall and free to slip against the inner lateral wall in the event of overtension of the mainspring (2). The end of the outer coil includes an external face (23) having two friction surfaces (24, 25) disposed in the top and bottom portion of the outer coil and arranged to be in contact with the inner lateral wall in such a way that the portion between the friction surfaces, referred to as central portion (26), is not in contact with the inner lateral wall, the central portion forming a reservoir (27) for a lubricant between the two friction surfaces.