Patent ID: 11921468
Assignee: NIVAROX-FAR S.A.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 20:
21. A production support tooling for implementation of a method for measuring a torque of a balance spring for a timepiece oscillator, said production support tooling including at least one main tool comprising a mock arbor of continuously increasing cross-section, on a rectilinear tool axis, from an apex in an upper part where an envelope diameter of said mock arbor is smaller than a passage diameter, to its base in a lower part where the envelope diameter of said mock arbor is greater than said passage diameter, said mock arbor comprising in the upper part an insertion guide, every section of which, in projection onto a plane perpendicular to said tool axis, is inscribed in an aperture of a collet, and wherein the envelope diameter of said mock arbor is always smaller than said passage diameter, said insertion guide being arranged for a first centring of said collet of said balance spring placed on said upper part and allowed to slide freely under its own weight along said insertion guide, and said insertion guide surmounting at least a lower shank of substantially frustoconical or obelisk shape and which is arranged to complete the self-centring of said collet on said tool axis, and to hold said balance spring without stress on said lower shank, and said lower shank including drive means which are arranged to cooperate with an inner surface of said collet to drive in rotation said mock arbor, without slipping, via said collet or vice versa, said production support tooling further including a holding tool, which is arranged to grip an outer coil of said balance spring, and measuring means arranged to make a measurement of the torque of said balance spring.