The Strutt Epicyclic Clock is unusual in design.
Designed by William Strutt of Derby in the 1820's it was manufactured in small numbers by William Wigston who had an engineering firm.
The epicyclic or sun and planet gear formed the going train, and an ingenious Ferguson's Paradox like system consisting of two gears on the same shaft and a lantern pinion produced the 12:1 reduction for the hour hand.
This version deviates from the original in that it is made of wood annd has a different layout but has the original teeth counts for the wheels.
All wheels are Module 1.5
The escapement is a 36 tooth inverted recoil escapement
A six tooth escapement pinion meshes with a large ring gear that has 168 teeth externally and 144 teeth internally.
The planet gear of 68 teeth runs around the internal of the ring gear, being mounted on a counter balanced carrier arm. Here the counter weights are 2p coins. The minute hand is mounted on a shaft projecting forward from the carrier.
An eight tooth laantern pinion on the planet gear meshes with two sun gears. The innermost one has 72 teeth and the outer one has 66 teeth and does not rotate.
Although they have different numbers of teeth they have the same pitch diameter, but they still mesh adequately with the lantern pinion.
By a geometrical process that I don't understand this arrangement means the inner wheel rotates at once per twelve hours and is thus connected to the hour hand.
This image shows the means of fixing the rotation of the 66 tooth sun wheel by prongs projecting from the escutcheon plate engaging a crossing of the wheel.
The escutcheon plate is fixed to the dial.
The large ring gear is driven from a gear on the same shaft but between the plates which is driven by a weight running a short arc around its periphery. The weight is a motor which gets switched on when it is low on the gear by a mercury switch and a 3 second timer, which lifts it up while still maintaining motive power to the clock.
The pendulum bob is just for display. There is an adjustable brass weight further up the pendulum shaft.
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