| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a manufacturing method of a balance spring that can highly accurately and easily adjust a rate of the balance spring made up of a crystal material.SOLUTION: A manufacturing method of a balance spring 10 that includes a collet 12 having a through-hole 12a for fitting with a rotating shaft body, and a coil-shaped main spring unit 11 being connected to the collet 12 in a connection unit 12b and being winded around the collet 12 centering around the through-hole 12a, and is obtained by machining a material having a prescribed crystal structure comprises: a rate measurement process of measuring a rate; and a laser irradiation process of irradiating a prescribed area E of the main spring unit 11 facing the connection unit 12b across the through-hole 12a of the collet 12 with a laser. The manufacturing method of the balance spring is configured to cause the laser irradiation to change an area E of the main spring unit 11 to amorphousness, which in turn adjusts the rate.</p> |
