| 摘要 |
PURPOSE:To make plate bridges, etc. common by permitting the selection of the rotating direction of a constellation display plate without changing the axial center positions of respective gears. CONSTITUTION:An hour wheel B31 makes one turn in 12hr in a clockwise direction viewed from a dial B35 side. An idler gear 25a of an idler wheel 25 engages simultaneously between an hour wheel pinion B31b of the wheel B31 and a adjusting gear B33a of an adjusting wheel 25a. The gear ratio between the pinion B31b and the gear B33a is made coincident with the gear ratio between the cannon pinion 11b and adjusting gear 13a of a timepiece 1 with a constellation display in which a constellation display plate 24 rotates in the clockwise direction. The constellation display plate B32 fixed to one end near the dial B36 of a constellation gear 17 engaged with the adjusting wheel pinion 13b of the wheel B33 makes one turn exactly at the prescribed speed, i.e., in one average sideral day in the counter-clockwise direction viewed from the dial B36 side. Such rotation coincides with the rotating condition of the constellation display plate B32 in which the declination decreases gradually from the center of rotation toward the outside periphery. |
