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 clock for indicating estimated time of arrival has a minute hand and hour hand for indicating present time in combination with a minute and hour hand which are set for estimated time of arrival (ETA). An ETA hour hand knob positioned above the crystal on the face of the clock has a hollow shaft which protrudes through a central aperture in the clock crystal. The ETA hour hand is mounted to the shaft and mounting tension for the hour hand knob is maintained by a spring washer between the ETA hour hand and clock crystal. An ETA minute hand knob has a shaft portion which coaxially protrudes through the hollow shaft of the hour hand knob. An ETA minute hand is securely fastened to the end of the minute hand knob shaft. A second spring washer is provided between a shoulder on the ETA minute hand knob and a top portion of the hour hand knob, the entire combination providing a simple, stable, individually settable ETA hour and minute hand set.
A timer includes a cam driven by a motor and a clutch for permitting the cam to be turned independently of the motor. The clutch includes a clutch plate having a toothed rim, the plate sandwiched between a pair of spring washers, and a tubular eyelet passing through openings in the plate and washers. The clutch assembly is placed on a mandrel and the washers are spun while the teeth on the plate engage a force gauge. The end of the eyelet is flared to fasten the clutch assembly together with a force which provides a predetermined torque between the plate and washer as measured by the force gauge.
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.
A three hand movement of the type having a frame, a stepping motor mounted in the frame, a manually actutable timesetting stem disposed in the frame and a gear train driven by the stepping motor to rotate coaxial members carrying "seconds", "minutes", and "hours" hands. An improved dual reduction gear assembly comprises a first rotatable member with a toothed wheel and a second rotatable member having first and second pinions driving the "hours" and "minutes" wheels. A timesetting gear is adapted to be clutched to the "minute wheel". A friction coupling connects the first and second rotatable members during timekeeping. During timesetting, the friction coupling slips to disengage the toothed wheel from the first and second pinions, so that the second rotatable member separately functions as a reduction gear during timesetting.
An improved reduction gear assembly with friction drive/slip coupling for a timepiece movement, comprising a metal pinion member having a toothed pinion and a coaxial stem extending from an abutment surface on said pinion, including (1) a cylindrical portion, (2) a frustum portion tapering from a smaller diameter to a larger diameter (3) a terminating tapered end portion; and a plastic wheel member having a toothed wheel and first and second coaxial journals extending from opposite sides of the. A central passage in the journals has a constricted section therein with a diameter slightly less than that of said larger diameter of said frustum portion on said metal pinion member with the frustum disposed in said constricted passage with a snap fit, whereby a friction drive/slip coupling is provided between the metal frustum portion of the metal pinion member and the constricted passage of the plastic wheel member.
