A Schwartzkopff-Eckhardt II bogie (Schwartzkopff-Eckhardt-II-Lenkgestell or Schwartzkopff-Eckhardt-Gestell) is a mechanical device to improve the curve running of steam locomotives.
The Schwartzkopff-Eckhardt II bogie is a further refinement of the Krauss-Helmholtz bogie, whereby two coupled axles and the carrying axle are combined within the bogie. The carrying axle steers the second coupled axle via a long shaft and this also moves the first coupled axle via a Beugniot lever. This bogie is used on the DRG Class 84. Whether DR Class 99.23-24 locomotives were also fitted with this arrangement is not entirely clear.
It was named after the L. Schwartzkopff locomotive factory and its chief engineer, Friedrich Wilhelm Eckhardt.
References
Schwartzkopff-Eckhardt II bogie Wikipedia(Text) CC BY-SA