Timepiece oscillator with flexure bearings having a long angular stroke

A mechanical timepiece oscillator, comprising:

• a flexure bearing mechanism disposed between a first rigid support element directly or indirectly fixed to a plate and a solid inertial element, the flexure bearing mechanism including at least two first flexible strips which support the solid inertial element and are configured to return the solid inertial element to a rest position, wherein
• the solid inertial element is configured to oscillate angularly in an oscillation plane about the rest position,
• the first flexible strips do not touch each other,
• projections of the first flexible strips onto the oscillation plane cross, in the rest position, at a crossing point,
• an axis of rotation of the solid inertial element passes proximate to the crossing point, the axis of rotation being perpendicular to the oscillation plane,
• the flexure bearing mechanism includes at least one upper level and at least one lower level superposed on each other,
• the at least one upper level includes, between an upper support and the solid inertial element, at least one upper primary strip extending in a first upper strip direction and one upper secondary strip extending in a second upper strip direction, the at least one upper primary strip and the one upper secondary strip being projected onto and crossed at an upper crossing point,
• the at least one lower level includes, between a lower support and the solid inertial element, at least one lower primary strip extending in a first lower strip direction and one lower secondary strip extending in a second lower strip direction, the at least one lower primary strip and the one lower secondary strip being projected onto and crossed at a lower crossing point,
• the upper level includes, between the plate and the upper support, an upper translational table,
• the lower level includes, between the plate and the lower support, a lower translational table,
• the upper translational table and the lower translational table comprise at least one elastic connection along one or two axes of freedom in the oscillation plane, and
• a stiffness of the at least one elastic connection is lower than a stiffness of the upper level and a stiffness of the lower level.