Watch family · Complication
Alarm Watches
Partially verifiedWatches fitted with a separate striking mechanism that sounds at a pre-set time, typically via a hammer on a bell or membrane rather than the gong of a repeater.
Movement & mechanism
- A separate mainspring and train dedicated to the alarm function, wound independently of the timekeeping train
- A hammer striking a bell (fitted to the case back in many classic wrist designs) or a metal membrane forming part of the case
- A rotating disc or hand set against the dial to select the alarm time, releasing the striking train at the chosen point
Identification
- A separate crown (typically a second, smaller crown) for setting and winding the alarm
- A rotating inner alarm-set ring or a dedicated alarm hand on the dial
- A vented or perforated case back on classic mid-century designs, to let the alarm sound clearly
Terminology
- Alarm train — the separate going train dedicated to sounding the alarm
- Membrane back — a case back designed to resonate and amplify the alarm sound
Known variations
- Single alarm watch
- World-time alarm watch
Pocket-watch ancestry
Alarm mechanisms existed in pocket watches from the early nineteenth century; the wristwatch alarm required a compact rework of the same separate-train, hammer-and-bell principle to fit a far smaller case.
Collecting notes
Mid-twentieth-century mechanical alarm wristwatches form a distinct and actively collected niche, valued for their mechanical ingenuity in a functional area later dominated by electronic watches.
Photographs
Photographs are illustrative examples of the type, not necessarily the exact object described. Verify details against the source file page.
Sources & references
- General horological literature on mechanical alarm mechanisms; exact origin dating for pocket alarm watches needs further research.
Where sources disagree, the disagreement is stated rather than resolved silently.