A battery-operated watch or clock has a knob which is axially shiftable been a first terminal position recessed in a rear housing wall and a second terminal position projecting therefrom. In the recessed position, in which the knob is manually rotatable upon removal of a battery cover surrounding same, its rotation resets both the minute and hour hands of the timepiece to enable its adjustment, especially upon a replacement of a spent battery. In the projecting position, such rotation only displaces the hour hand to facilitate a changeover between standard and daylight-saving time or an adjustment to a different time zone.
The timepiece has a gear housing containing a horometric movement and a minute hand gear 12 operatively connected to the movement. Also, the timepiece comprises a drive gear 2 operatively connected to the movement, a cylinder gear 4 engaging the drive gear 2 by crown teeth 24 disposed on both gears 2 and 4, a leaf spring 6 biasing the cylinder gear 4 against the drive gear 2, a rod 8 and a sliding switch 10 pivotally disposed on the rod 8. The sliding switch 10 has a switch tooth 68 that removably engages the cylinder gear 4, forcing the crown teeth 24 to slide into an adjacent position which independently moves an hour hand 54. Other embodiments employ a spindle switch 78 and a pop-up switch 88.
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.
A motor actuates a wheel train which drives center hour and minute hands as in an ordinary analog-display watch. Another motor actuates a chronograph train which drives a chronograph sweep seconds-hand, a minute-register hand, and an hour-register hand offset toward 6 o'clock. A lever actuates a column wheel which starts and stops the second motor by means of a control lever integral with a stem. A hammer resets the chronograph gears. An electronic circuit comprises a liquid-crystal display element which displays the hundredths of a second when the chronograph is running or the date when the chronograph is not running.
