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 a ratchet 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 first one-way ratchet, and is held in place during setting of the auxiliary hour hand by a second one-way ratchet utilizing weak radial spring arms.
A clutch permits rotation of a cam means from one drive means independent of another. The clutch is operable through at least two diametrically opposed fingers engaging slots which are provided on a gear, the gear being part of a gear train for the motor drive means.
A clock for indicating moon phase comprises a moon phase dial fixed to a hub rotatable around an axle for indicating the moon phase according to the angular position thereof relative to the axle. The moon phase dial has a set of circumferentially spaced peripheral projections manually engageable during correction of the angular position thereof. A moon phase gear is slideably disposed around the hub and is driven to continuously rotate around the axle at a rotation period related to the moon phase period. A slip mechanism is disposed between the moon phase dial and the moon phase gear and frictionally engages between the face of the moon phase gear which is opposed to the moon phase dial and the periphery of the hub. The slip mechanism is operative during the correction of the angular position of the moon phase dial for decoupling the moon phase gear from the hub so as to enable the moon phase dial to rotate independently of the moon phase gear, and operative during the normal operation of the clock for coupling the moon phase gear to the hub so as to enable the moon phase dial to continuously rotate in response to the rotation of the moon phase gear.
