A power transmission body of a timepiece in which a fixed portion between an arbor and a power transmission member is hardly damaged is provided without increasing the number of components. A transmission wheel (one example of power transmission body) includes a gear and a pinion (one example of arbor). A hole formed in a center portion of the gear includes a regular octagon with a rotation center as a center. An insertion portion formed in the pinion includes a gear-like portion including a tooth bottom and a tooth tip. The hole includes eight portions that are positioned in a circumference direction about the rotation center and contact the insertion portion. The hole includes a portion that is positioned in front of the eight portions in a clockwise direction (specific rotation direction) about the rotation center and has a distance from the rotation center longer than a distance from the rotation center to each of the eight portions.

An escape wheel (an example of a timepiece component) has a silicon-made substrate having an insertion portion into which an axle is inserted, and a coating film formed in a contact portion which comes into contact with at least the axle, at a surface of the substrate. The coating film contains metal alkoxide having a fluorine atom.

An escape wheel & pinion serving as a mechanical component includes an axle and an escape wheel serving as a rotary member having a holder for holding the axle. The axle has a recessed portion into which the holder is fitted. A tapered portion inclined in an axial direction of the axle is disposed in a portion where the recessed portion is in contact with the holder.

Provided are a mechanical part, a timepiece having the mechanical part, and a method of manufacturing a mechanical part that suppresses separation and rotation of a rotating member to a staff member, and can be manufactured at a competitive cost. A escape wheel and pinion 35 as an example of a mechanical part has a staff member 102; an escape wheel 101 with a hole 115 to which the staff member 102 is inserted, and ribs 112 that extend toward the staff member 102; and an annular fastening member 130 that affixes the escape wheel 101 to the staff member 102. The fastening member 130 is disposed touching the ribs 112 and deforming to protrude into the hole 115.

An escape wheel and pinion includes an escape wheel that has an axle, a web arm which holds the axle, and a rim which has a plurality of teeth. The web arm has a spoke which radially extends from the rim, and a comb including a radial spine and cross beams branching from the spoke.

Timepiece mechanism comprising a structure in which at least one arbor of a wheel set is pivoted about an axis of rotation, and comprising a braking device for the mechanical braking at constant torque of this arbor, the braking device comprises a braking component which is removable with respect to the structure and comprises, for attachment thereof to the structure, a solid felloe, which carries a plurality of resilient elements, regularly distributed around a common axis about which these resilient elements each have a contact area. the contact areas together defining an opening, arranged to engage, in a press fit with elastic gripping, with the arbor, to make the common axis coincide with the axis of rotation of the arbor, and to apply to the arbor a substantially constant tangential braking force.

Disclosed is a flexible-pivot mechanical component of the type with separate intersecting blades, particularly for timepieces. The mechanical component includes an attachment portion and a movable portion that are connected by first and second resilient blades that intersect in a contactless manner at an intersecting point. The flexible-pivot mechanical component is combined with an adjustment unit making it possible to adjust the position of the intersecting point.

The invention relates to a method (19, 19, 39, 39, 59, 59) of assembling a part (5, 5, 25, 25, 45, 45) in the aperture (18, 18, 38, 38, 58, 58) of a component (3, 3, 23, 23, 43, 43). According to the invention, the assembly system (19, 19, 39, 39, 59, 59) includes a system (1, 1, 21, 21, 41, 41) of securing the component (3, 3, 23, 23, 43, 43) and the part (5, 5, 25, 25, 45, 45) to each other, which includes at least one pawl device (11, 11, 31, 31, 51, 51) intended to make the component (3, 3, 23, 23, 43, 43) and the part (5, 5, 25, 25, 45, 45) move integrally with each other. The invention concerns the field of timepieces.

A timepiece shaft (1), especially a balance shaft (1), comprising a first functional portion (2a; 2b) including at least one part (221a; 221b) of a pivot-shank (22a; 22b) and/or at least one part (211a; 211b) of a pivot (21a; 21b), the first functional portion being made of ceramic and a first outer diameter (D1) of the first functional portion being less than 0.5 mm, or less than 0.4 mm, or less than 0.2 mm, or less than 0.1 mm.

A motor module for a horological movement, the motor module including a plate bearing one or more cogs, and a cog bridge mounted on the plate, wherein the cog bridge includes a device for clipping the cog bridge onto the plate.