A bearing includes a shaft which pivots in the bearing. The shaft includes, at at least one end thereof, a shoulder via which the shaft is in contact with an opposite surface of the bearing. The shoulder is extended by a pivot engaged in a hole provided in the bearing. The opposite surface of contact of the bearing includes at least one hollow in order to reduce the surface of contact between the shoulder of the shaft and the bearing. Application is made to the production of a bearing for a shaft of a horology movement.

A method for manufacturing a jewel for a timepiece, the jewel including, for example, poly-ruby of the Al2O3Cr type or Zirconia of the ZrO2 type, including first producing a precursor and a then pressing the precursor in order to form a body, the pressing being carried out using a pressing device provided with an upper die and a lower die defining a pressing space wherein the precursor is disposed, the upper die including a concave portion of oblong shape, the device having a wire at least partially traversing the lower die to open into the pressing space, the lower die being able to slide around the wire, the pressing being carried out by bringing the lower die and the upper die closer together to form a body including an upper face provided with a dome and a lower face provided with a hole extending at least partially into the dome.

A method and device for manufacturing a bevelled stone, particularly for a timepiece are disclosed. A precursor is produced from a mixture of at least one material in powder form with a binder. The method includes pressing the precursor so as to form a green body, using a top die and a bottom die comprising a protruding rib, sintering the green body so as to form a body of the future stone in at least one material, the body including a peripheral face and a bottom face provided with a groove, and machining the body including a substep of planning the peripheral face up to the groove, such that an inner wall of the groove forms at least a flared part of the peripheral face of the stone.

A shock absorber bearing for an arbor of a timepiece wheel set, particularly for a balance staff. The bearing includes a bearing assembly including a housing, a bearing support arranged inside the housing and including an external centring wall, a pivot bearing mounted on the bearing support for receiving a pivot of a wheel set arbor and an elastic support arrangement for the wheel set arbor pivot. The shock absorber bearing further includes a device for recentring play. This device for recentring play includes, on the one hand, a first part including a centring element having an internal centring wall in which is arranged the external centring wall of the bearing support, and on the other hand, a second part resting on the bearing assembly and arranged to have a return effect on the first part.

A rotary wheel set system of a horological movement with a rotary wheel set, a first and a second bearing, for a first and a second pivot of the arbor of the rotary wheel set, the wheel set including a mass center in a position of its arbor, the first bearing including an endstone including a main body equipped with a pyramidal cavity configured to receive the first pivot of the arbor of the rotary wheel set, the cavity having at least three faces giving its pyramidal shape, the first pivot being capable of cooperating with the cavity of the endstone to rotate in the cavity, at least one contact zone between the first pivot and a face being generated, the normal at the contact zone or zones forming a contact angle (.sub.h) relating to the plane perpendicular to the arbor of the pivot, wherein the contact angle (.sub.h) is less than 45.

A rotary wheel set system of a horological movement with a rotary wheel set, a first and a second bearing, for a first and a second pivot of the arbor of the rotary wheel set, the wheel set including a mass center in a position of its arbor, the first bearing including an endstone including a main body equipped with a pyramidal cavity configured to receive the first pivot of the arbor of the rotary wheel set, the cavity having at least three faces giving its pyramidal shape, the first pivot being capable of cooperating with the cavity of the endstone to rotate in the cavity, at least one contact zone between the first pivot and a face being generated, the normal at the contact zone or zones forming a contact angle (.sub.h) relating to the plane perpendicular to the arbor of the pivot, wherein the contact angle (.sub.h) is less than 45.

A bearing includes a shaft which pivots in the bearing. The shaft includes, at at least one end thereof, a shoulder via which the shaft is in contact with an opposite surface of the bearing. The shoulder is extended by a pivot engaged in a hole provided in the bearing. The opposite surface of contact of the bearing includes at least one hollow in order to reduce the surface of contact between the shoulder of the shaft and the bearing. Application is made to the production of a bearing for a shaft of a horology movement.

A method for manufacturing a hole jewel, including forming a precursor from a mixture of at least one powder material with a binder; pressing the precursor, with upper lower dies, to form a green body of the future hole jewel including a blind cavity having a height between a height of the green body and a height of the future hole jewel, the cavity being provided with upper and lower portions respectively including blanks of a through hole and of a functional element of the future hole jewel; sintering the green body to form a body of the future hole jewel; machining the body, including a first sub-step of shaping a top of the body, during which a height of the upper portion is configured in readiness for an opening in the through hole blank for connecting the functional element to the upper surface, and a second sub-step of shaping a base of the body to form a lower surface of the hole jewel for connecting the functional element to to the lower surface.

A method for manufacturing a hole jewel, including forming a precursor from a mixture of at least one powder material with a binder; pressing the precursor, with upper lower dies, to form a green body of the future hole jewel including a blind cavity having a height between a height of the green body and a height of the future hole jewel, the cavity being provided with upper and lower portions respectively including blanks of a through hole and of a functional element of the future hole jewel; sintering the green body to form a body of the future hole jewel; machining the body, including a first sub-step of shaping a top of the body, during which a height of the upper portion is configured in readiness for an opening in the through hole blank for connecting the functional element to the upper surface, and a second sub-step of shaping a base of the body to form a lower surface of the hole jewel for connecting the functional element to to the lower surface.

Watch movement including a frame comprising a first bearing and a second bearing, and a tourbillon comprising two cages, of which one cage is known as the external cage, the external cage being mounted in a pivoting manner on the frame between the first bearing and the second bearing, the movement comprising in addition two watch jewels supporting two pivots of the external cage, wherein the movement includes two translational elements capable of displacement in relation to the bearings in the axis of rotation of the external cage in the assembled position of the external cage on the frame, so as to cause a displacement of the watch jewels or a displacement of the pivots.