Krauss-Helmholtz bogie
The Krauss- Helmholtz bogie is used in steam locomotives and some electric locomotives body to improve cornering characteristics. In the steering rack (not driven ) Running axis is connected via a drawbar with a ( driven ) coupled axle that the radial pivoting of the barrel axis causes an opposite lateral displacement of the dome axis. Thereby, the lateral forces are absorbed in cornering approximately equal parts by two axes, bringing the running characteristics which approximate a bogie and the wear of wheel flanges and rails is reduced. The steering rack is named after the locomotive factory Krauss and their chief designer Richard von Helmholtz, inventor of the device.
In contrast to Krauss- Helmholtz bogie a bissel is mounted independently within the vehicle, and the lateral guidance of the engine is effected by spring forces. The distribution of forces is not well defined and also depending on the curve radius.
Because a steering rack can show its advantages, especially in tight corners, it was first used in addition to rail, local railway and narrow gauge locomotives. One of the first locomotives to the steering rack was the Bavarian D VIII This tank locomotive, the frame was back; in the majority of cases, however, it was the front or - if the locomotive in both directions should have equally good running properties - located at both ends of the locomotive.
Later, the steering rack prevailed even with larger and more powerful locomotives, such as the standard locomotives of the Deutsche Reichsbahn; e.g. in the five -coupled series 44, 45, 50 and 85 The Tender locomotives of series 41 and 45 had only one front Krauss- Helmholtz bogie; the trailing axle was mounted in a bissel. The tender locomotives of Class 85, however, possessed as a part of series 64 and 86 on two Krauss- Helmholtz steering racks.
The electric locomotives of the Reichsbahn series E 04, E 17, E 18 and E 19 were equipped with similar steering racks, called AEG- Kleinow frame. Because the axles are mounted outside, the articulation of the steering lever had to be done outside, a characteristic detail of these locomotives.
When Krauss -Helmholtz - frame, the first coupled axle is still burdened with a substantial part of the tracking force because the second coupled axle with their rigid storage and weakened flanges does not absorb lateral forces. Therefore, the Kurvenläufigkeit was further improved by the Schwartzkopff Eckhardt steering racks in the unit locomotives of Class 84.
In Swiss electric locomotives, the Krauss- Helmholtz bogie was developed for Java - frame, in which the drive axle radial setting thanks to the Buchli Einzelachsantriebs.