A small brass synchroniser made by the Croydon firm Gillett & Johnston, probably in the 1930s. This synchroniser was an optional extra that could be installed in an electric clock to synchronise it by reference to an external source – such as a more accurate clock, or an electric time signal. A pivoted arm carries a small weight which can be raised or lowered onto a weight tray on the pendulum to adjust the rate.
Technical description
An hourly pulse is sent from a controlling clock circuit. The clock with the synchroniser is set to lose a little, and the weight suspended below the mechanism is dropped onto the weight tray as required to bring the clock back to time each hour. At the left-hand side, there is a brass counterweight, with a wire lever passing through it, pivoted at the top. The wire continues across the plate and carries a triangular detent-block, which is raised or lowered by the snail cam on the wheel.
Inventory number
TCW 1075
Date
1930s
Bibliography
John Hubert, ‘Gillett & Johnston Synchroniser’, via Clockdoc
