Abstract: The present invention concerns an assembly for holding or supporting a timepiece balance spring, comprising a balance spring stud and a balance cock on which is fixed a balance spring stud-holder, wherein said stud-holder comprises a holding means provided with a housing for housing the balance spring stud therein and a gripping means, at least said gripping means being movable with respect to the holding means in order to lock the balance spring stud inside its housing.

Abstract: A timepiece power source is provided, including a barrel containing a mainspring mounted between a drum and an arbor rotating integrally with a ratchet wheel, including a differential gear coaxial to the barrel, with a first input driven by the ratchet wheel, a second input which is the drum, and a pivoting output wheel, coaxial to the arbor, arranged to form or to drive a power reserve indicator, the differential gear including balls driving the output wheel, cooperating with an upper surface of the drum, and with a lower surface, which is opposite thereto, of a differential plate forming the first input, pivoting coaxially on the arbor and connected to the ratchet wheel by a friction means cooperating with a plate, and the ratchet wheel forms the cover of the barrel.

Abstract: A method for making an oscillating weight for an automatic winding mechanism of a self-winding watch including a central part made from a first composite material and a heavy sector made from a second composite material charged with heavy metal particles, the method including: forming the central part with a lateral rib and a rebate by injecting the first composite material into a mold; overmolding the heavy sector onto the central part by injecting the second composite material into a mold containing the central part, so that the second composite material fills the rebate and a gap underneath the lateral rib, so that the lateral rib is embedded in the second composite material and the central part and the heavy sector are interlocked.

Abstract: The present invention concerns an assembly for holding or supporting a timepiece balance spring, comprising a balance spring stud and a balance cock on which is fixed a balance spring stud-holder, wherein said stud-holder comprises a holding means provided with a housing for housing the balance spring stud therein and a gripping means, at least said gripping means being movable with respect to the holding means in order to lock the balance spring stud inside its housing.

Abstract: A timepiece power source is provided, including a barrel containing a mainspring mounted between a drum and an arbor rotating integrally with a ratchet wheel, including a differential gear coaxial to the barrel, with a first input driven by the ratchet wheel, a second input which is the drum, and a pivoting output wheel, coaxial to the arbor, arranged to form or to drive a power reserve indicator, the differential gear including balls driving the output wheel, cooperating with an upper surface of the drum, and with a lower surface, which is opposite thereto, of a differential plate forming the first input, pivoting coaxially on the arbor and connected to the ratchet wheel by a friction means cooperating with a plate, and the ratchet wheel forms the cover of the barrel.

Abstract: A method for making an oscillating weight for an automatic winding mechanism of a self-winding watch including a central part made from a first composite material and a heavy sector made from a second composite material charged with heavy metal particles, the method including: forming the central part with a lateral rib and a rebate by injecting the first composite material into a mold; overmolding the heavy sector onto the central part by injecting the second composite material into a mold containing the central part, so that the second composite material fills the rebate and a gap underneath the lateral rib, so that the lateral rib is embedded in the second composite material and the central part and the heavy sector are interlocked.

Abstract: Timepiece assembly (30) including at least two opposing wheel sets (20), coupled to each other and cooperating by contact with each other on peripheral contact surfaces (200). Each peripheral contact surface (200) of each coupled wheel set (20) in this assembly (30) is the peripheral surface of a skin (210) of plastic material.