US 11,054,791 B2
Timepiece rate adjustment method
Thierry Conus, Lengnau (CH); and Pascal Winkler, St-Blaise (CH)
Assigned to ETA SA Manufacture Horlogere Suisse, Grenchen (CH)
Appl. No. 16/316,388
Filed by ETA SA Manufacture Horlogere Suisse, Grenchen (CH)
PCT Filed Jun. 13, 2017, PCT No. PCT/EP2017/064426
§ 371(c)(1), (2) Date Jan. 9, 2019,
PCT Pub. No. WO2018/015071, PCT Pub. Date Jan. 25, 2018.
Claims priority of application No. 16179847 (EP), filed on Jul. 18, 2016.
Prior Publication US 2019/0302700 A1, Oct. 3, 2019
Int. Cl. G04D 7/08 (2006.01); G04D 7/12 (2006.01)
CPC G04D 7/1285 (2013.01) [G04D 7/085 (2013.01); G04D 7/088 (2013.01); G04D 7/1264 (2013.01); G04D 7/1292 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for adjusting a rate of a timepiece comprising:
placing a movement including a balance/balance spring resonator inside a timepiece case without a back cover or without a whole of the back cover;
measuring a rate of the timepiece;
determining a correction value to be applied to a balance inertia to obtain a desired rate;
altering the balance inertia according to the correction value by adding material to the balance by fitting the movement into the case without the back cover or without the whole of the back cover.