Friction detent to permit setting of digital clock

A setting mechanism for a drum-type digital clock having a minute drum with a central web, fixed to and rotating with a shaft, comprising in combination

• a drive disc mounted on and rotatable with respect to said shaft,
• a detent member keyed to the drive disc for rotation therewith, but having limited axial freedom with respect to both the drive disc and the minute drum,
• resilient means pressing said detent member toward the web of said minute drum,
• mating surfaces on said web of said minute drum and on the adjacent face of said detent member, said mating surfaces being adapted to interfit at a fixed number of rotated positions of said minute drum with respect to said detent member,
• actuating means adapted to advance the drive disc each minute, and
• setting means engageable with said shaft, adapted to rotate said minute drum independently of said detent member by the application of sufficient torque to said minute drum to force said mating surfaces to withdraw from interfitting relation.

A setting mechanism for a drum-type digital clock having a drum with a central web, mounted on a shaft, comprising in combination

• drive means rotatable with respect to said shaft,
• a detent member keyed to the drive means for rotation therewith, but capable of axial movement with respect to said drive means and said drum,
• resilient means biasing said detent member toward the web of said drum,
• a boss projecting axially from said detent member and engageable with any of a plurality of recesses in the web of said drum,
• actuating means adapted to advance the drive means periodically, and to restrain the drive means against rotation between advance periods, and
• setting means adapted to rotate said drum independently of said detent member by the application of sufficient torque to said drum to force said boss to withdraw from engagement with said recesses.