| 摘要 |
PURPOSE:To realize a simple and convenient constitution for the world time watch with no operation required for the date change, by correcting the time differential through rotation of the rotor and then detecting both the position and the rotational direction of the date line. CONSTITUTION:When the rotary disk is turned clockwise, the holes drilled every 15 degrees cross the lamp. Thus the count contents of reversible counter 86 is advanced and then displayed at the display part. At the same time, the pulse is generated at output J of selecting circuit I, and FF77 is triggered to retain the input of AND gate 84 at 1. After this, the hole on the date line of the disk crosses the lamp, and thus the pulse is generated at output H of the photodetector to be supplied to gate 84. Accordingly, the output of gate 84 rises up and is then supplied to signal control circuit II. As in the case of correction of the time differential, the count contents of reversible counter 78 is advanced by 1 along with the data advanced by one day. In case the rotary disk is turned counterclockwise and the hole on the date line crosses the lamp, the count contents of counter 78 is subtracted by 1. |
