| 摘要 |
PROBLEM TO BE SOLVED: To prevent or suppress the influence to a rate generated by the increase of a solid frictional resistance when a balance is in an inclined attitude in the movement of a mechanical timepiece, without depending on coating treatment.SOLUTION: A movement 100 of a mechanical timepiece includes: a balance 17 vibrating around a balance staff 18; and a viscous frictional resistance adjustment mechanism 99 making a viscous frictional resistance force generated in the balance 17 vibrating in the inclined attitude of the balance 17 smaller than the viscous frictional resistance force generated in the balance 17 vibrating in a horizontal attitude of the balance 17. The viscous frictional resistance adjustment mechanism 99 includes: a flow hole 92 formed in the portion of a bottom board 90 to which the balance 17 faces; a lid member 95 formed large enough to cover the flow hole 92; and a lid arranging mechanism 98 for arranging the flow hole 92 at a closed position when the balance is in a horizontal attitude, and arranging the flow hole 92 at an open position when the balance 17 is in the inclined attitude.SELECTED DRAWING: Figure 2 |
