Horological Meandering

Heinrich
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From a scientific point of view ...

Bahne Bonniksen's original layout of the karrusell escapement seems to have the balance wheel 'E' in the center of the platform as can be seen from the drawings in the Swiss patent No. 7965 dated 27. January 1894.

From a scientific point of view there is a considerable difference between the tourbillon escapement and the karussell escapement. The scetch below shows three different gear diagrams. Such diagrams are e.g. used to analyse planetary gear topologies for automotive drivetrains, but are good for watch movements as well ;-)

The top one belongs to the standard escapement: Three reduction gear sets are put in a line to change the speed from the minute wheel to the escapement wheel. The escapement wheel is peridocally released by the escapment.

The gear diagram in the middle belongs to a tourbillon escapement: The reduction gear following the intermediate wheel is no longer a simple reduction gear with the cage fixed to the housing of the movement, but a tourbillon with the cage rotating and the output shaft fixed to the housing of the movement (ususallly a fixed second wheel).

The lower gear diagram describes Bahne Bonniksen's karussell escapement. The escapement is fitted to a rotating platform which is driven from the intermediate wheel via a gear set. The characters in the scetch refer to the drawing in Bahne Bonniksen's patent. Please note that this layout cannot be adapted to have the platform running at 1 revolution per minute. As faster the platform spins as slower needs the escapement wheel to run in order to maintain the 1 revolution per minute at the pinion 'A'.  At 1 revolution per minute the escapement wheel would have to run at zero speed which is impossible. From my point of view the advantage of Bahne Bonniksen's invention is the fact that the impact of the friction in the platform bearings on the accuracy of the movement is 52.5 times lower compared to the 1 minute tourbillon. The reflected inertia of the platform is even by the factor of 52.5 times 52.5 smaller than the one of a tourbillon cage. 

I hope I wasn't getting too academic now

Best regards from Germany

Heinrich