The termination arrangement comprises a two conductor hairspring and/or hub arrangement in an electric watch for coupling drive pulses to a balance wheel drive coil. A metallic hairspring, which is fastened to the hub, has a conductor which is insulated from the hub and balance wheel staff or arbor. A contact - metallic washer like - member is bonded to the hairspring collet such that the contact member is electrically insulated from the hairspring colet. The contact member is, also, electrically connected with one end of the second conductor on the hairspring. And a helical type spring-conductor having less than one full turn in length is bonded to the balance wheel between the hairspring-hub arrangement and the contact member. The helical type spring at the end which is bonded to the balance wheel is electrically connected to one end of the balance wheel drive coil. The other end of the spring-conductor is maintained in electrical contact with the contact-washer member by the pressure of the spring. In this manner, a termination arrangement is provided for a two conductor hairspring and/or hub arrangement in an electrical watch which is capable of coupling drive pulses to a balance wheel drive coil and which facilitates the removal and setting of the hairspring or balance wheel by automatically making electrical contact without requiring soldering, etc.
A method for manufacturing a balance-spring for a clockwork movement wherein a spring is formed by winding, from a wire or metal strip, said spring including an inner end intended to be fixed to a balance and a outer end zone intended to be fixed to the balance-spring stud and wherein the whole spring is subjected to a first heat treatment subsequent to the winding step of said wire. The method of the invention is characterized in that it further includes an additional step consisting in subjecting at least said outer end zone to a second heat treatment. This method improves in particular the shock resistance of the balance-spring.
The anti-trip device is for a detent escapement mounted on a wristwatch. It includes a finger fixed to the arm of the balance, two columns between which the finger can pass, said columns being secured to the balance bridge, and a locking arm fixed to the outer coil of the balance spring, said locking arm being able to be inserted between said columns and said finger to prevent the balance from rotating beyond an angle exceeding its normal operating angle. The locking arm is a clamp hooked onto the outer coil of the balance spring.
