Component record · Dial & hands
Minute Wheel
VerifiedA wheel-and-pinion component in the motion works that connects the cannon pinion to the hour wheel.
What it does
Reduces the cannon pinion's once-per-hour rotation down to the hour wheel's once-per-twelve-hours rotation, driving the hour hand.
How it works
The minute wheel meshes with the cannon pinion on one side and, through its own pinion leaves, with the hour wheel on the other, providing the 12:1 gear reduction that keeps the hour hand at one-twelfth the angular speed of the minute hand.
It is mounted on a separate stud pressed or screwed into the pillar plate rather than being coaxial with the centre arbor, distinguishing it structurally from the cannon pinion and hour wheel, which do share the movement's central axis.
Evolution
Essentially unchanged in principle since the standardisation of separate motion works.
Known variations
- Minute wheel and pinion as a single component (most common)
- Compound minute wheel arrangements in calendar or multi-function motion works
Identification for collectors
- Visible on the dial side as the wheel positioned off-centre between the cannon pinion and hour wheel
- On many calibres the minute wheel turns on a fixed post in the main plate; a worn post lets the wheel tilt and the hands catch
Common failure modes
- Worn pivot causing the hour hand to run unevenly
- Broken or missing minute wheel stopping hour hand advance entirely
Photographs
Photographs are illustrative examples of the type, not necessarily the exact object described. Verify details against the source file page.
Sources & references
- de Carle, D., Practical Watch Repairing
Where sources disagree, the disagreement is stated rather than resolved silently.