Ttimepiece having a driving wheel including a hole with projections disengageable with a crown shaft

A timepiece comprising:

• an inner rotating ring including a plurality of first teeth;
• an operation part including a head and a shaft, the operation part being configured to move along a rotation axis of the shaft by push and pull operations by a user;
• and
• a driving wheel that is ring-shaped, the driving wheel having a plurality of second teeth in an outer surface and a plurality of projections in an inner surface to form a hole, the hole being engageable with and disengageable from the shaft, the plurality of second teeth being configured to mesh with the plurality of first teeth at a first engagement position, wherein
• the plurality of projections are disposed at intervals of an angle smaller than 90° and protrude toward the rotation axis of the shaft,
• the shaft of the operation part is configured to engage with the plurality of projections of the driving wheel at a second engagement position, and
• the first engagement position is shifted from the second engagement position along the rotation axis in a plan view.