| 摘要 |
The invention relates to a balance/hairspring assembly comprising a balance swinging about a balance arbour and a hairspring in which an inner coil is attached to the balance arbour or to a ferrule mounted secured to the arbour and in which an outer coil is attached to a stud secured to a bridge, the balance including a hub, a felloe, an arm connecting the hub to the felloe, a front surface having a countersink and a rear surface, the arm comprising an opening for receiving and holding a counterweight, and the hairspring being mounted opposite the front surface of the balance. According to the invention, the counterweight is mounted on the arm on the side of the rear surface of the balance, the distance between the bottom of the countersink of the front surface of the balance and the hairspring is within a predetermined interval of 0.05 mm to 1.50 mm. |
