MECHANISM FOR SECURING A BALANCE SPRING STUD TO A BALANCE BRIDGE AND SPRUNG BALANCE REGULATING DEVICE INCLUDING SUCH A MECHANISM

摘要

The regulating device includes an inertial balance (7) including a balance staff arranged to be pivotally mounted in the timepiece, a balance bridge (9) and a bearing (11) carried by the balance bridge and arranged to hold one end of the balance staff, a balance spring (1) including an inner end integral with the balance and an outer end (1a) integral with a stud (3;103), and a mechanism for securing the stud (3; 103) including a housing (17) for receiving the stud and which is formed in a stud holder (5) pivoted on the balance bridge (9), the securing mechanism further including an elastic arm (15; 115) arranged to pivot concentrically to the balance staff between a first position where the elastic arm immobilises the stud (3; 103) and a second position where the elastic arm is disengaged from the stud to allow the stud to be inserted into or removed from the housing.