A universal timepiece comprises a disc driven by means comprising meshing first and second planet wheels pivotally mounted on a rotatably carrier angularly fixed with the disc, the first planet wheel meshing with a pinion in an hours hand driving train, and the second planet wheel meshing with a solar pinion. The solar pinion is normally angularly fixed, but a setting train for the disc meshes with the solar pinion to enable rotation thereof.
A horological device with a regular hour hand and including an auxiliary hour hand for indicating a different time zone than the local time. The auxiliary hour hand is connected to the regular hour hand through a coupling member permitting relative rotation between the regular hour hand and the auxiliary hour hand when the crown is rotated in one direction and permitting normal setting of the hour hand and minute hand, with the auxiliary hour hand moving in unison, when the crown is rotated in the opposite direction. The coupling member is normally driven by the hour wheel through a peripheral friction coupling, and is held in place during setting of the auxiliary hour hand by a one-way ratchet utilizing weak radial spring arms.
A wristwatch with a stepping motor driving the hands through a normal gear train also includes a supplementary gear train driving a circumferential date ring showing the calendar date. The gear train includes a planetary gear assembly, which may also be selectively operated by an exterior manually rotatable button to change the date without interfering with the normal driving of the date ring from the stepping motor. Preferably the manually rotatable button is operable from the back of the watch using a ball-point pen or the like.
