An electro-mechanical mantel clock made by Louis-Constantin Detouche to a design patented by clockmaker, inventor and magician Jean-Eugène Robert-Houdin in 1855. Robert-Houdin’s aim had been to create a relatively inexpensive clock for popular domestic use, and this clock, which retailed at a modest 60 francs, was powered by readily available Daniell cells. Detouche and Robert-Houdin exhibited it along with several other electrical products at the 1855 Exposition Universelle, where it won a gold medal.
There is a contact at the bottom left which would originally have sent time impulses to a secondary dial.
Technical description
The pendulum carries two upward-curving arms, one on each side, which alternately engage two flat horizontal springs. One spring carries an electrical contact and, when touched by the pendulum, closes the circuit to an electromagnet, causing an armature to be attracted. The movement of the armature raises a vertical rod, which lifts the horizontal spring on the opposite side and allows a detent to engage. The spring is thus left in a tensioned, latched position. As the pendulum returns on the following half-swing, its opposite curved arm momentarily lifts the latched spring, releasing the detent. The stored energy of the spring is then discharged, imparting a brief downward impulse to the pendulum before the mechanism is reset. The cycle is repeated alternately on each side. The pendulum is therefore driven by a purely mechanical impulse of effectively constant force, while the electromagnet serves only to reset the impulse mechanism, making the operation largely independent of variations in battery strength.
Dimensions
43 x 31 x 14 cm (cased)
Inventory number
TCW 3009
Date
c.1855
Bibliography
Françoise Collanges, Conservation of an Early Electric Master Clock: Making a Copy as a Conservation Tool, MA thesis (unpublished), West Dean college 2012.
