Beugniot lever
Encyclopedia
The Beugniot lever is a mechanical device used on a number of locomotive
s to improve curve running. It was named after its inventor Edouard Beugniot.
Around 1860, when Beugniot was the chief engineer at the firm of Köchlin
, he developed a system whereby wheelsets
are housed in pairs in the locomotive frame
, with side-play, and connected by a lever. These levers are fixed to the frame in the centre and thus enable the sideways movement of the connected axles in opposite directions. In this way, instead of being fixed in the frame, the axles are able to move sideways rather like a bogie
, but clearly nowhere near as much. On locomotives with a side rod drive, the axle side-play is balanced using longer coupling pins (Kuppelzapfen) on which the coupling rods are also able to move sideways.
On running round a bend, the first axle is pushed sideways by the curve of the rails and so moves the second axle parallel to it in the opposite direction, until the wheel flanges of both axles align with the rails. This distributes the guide forces between the two axles which reduces wear and tear on the wheel flanges. By enabling this transverse movement of the wheelsets, locomotives with rigid frames do not have to use the thinner wheel flanges etc. normally needed to facilitate smooth running through points, bends and tightly curved sections of track. The 'guide length' of the locomotive is formed by the distance between the two fixed Beugniot lever pivot points.
In Germany, Beugniot levers were used mainly in the middle of the 20th century. The best known examples of locomotives that use this type of lever are the MaK
side-rod drive locomotives, the Class 105 and 106 engines in East Germany as well as steam locomotives like the DB Class 82
.
-Baureihen 600 D, 650 D und 1200 D
Locomotive
A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
s to improve curve running. It was named after its inventor Edouard Beugniot.
Around 1860, when Beugniot was the chief engineer at the firm of Köchlin
Koechlin family
The Koechlin family was an Alsatian family which acquired its wealth in the textile industry and became leading industrialists and politicians of the region.-Early family history:...
, he developed a system whereby wheelsets
Wheelset (railroad)
A wheelset is the wheel-axle assembly of a railroad car. The frame assembly beneath each end of a car, railcar or locomotive that holds the wheelsets is called the bogie...
are housed in pairs in the locomotive frame
Locomotive frame
A locomotive frame is the structure that forms the backbone of the railway locomotive, giving it strength and supporting the superstructure elements such as a cab, boiler or bodywork. The vast majority of locomotives have had a frame structure of some kind...
, with side-play, and connected by a lever. These levers are fixed to the frame in the centre and thus enable the sideways movement of the connected axles in opposite directions. In this way, instead of being fixed in the frame, the axles are able to move sideways rather like a bogie
Bogie
A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...
, but clearly nowhere near as much. On locomotives with a side rod drive, the axle side-play is balanced using longer coupling pins (Kuppelzapfen) on which the coupling rods are also able to move sideways.
On running round a bend, the first axle is pushed sideways by the curve of the rails and so moves the second axle parallel to it in the opposite direction, until the wheel flanges of both axles align with the rails. This distributes the guide forces between the two axles which reduces wear and tear on the wheel flanges. By enabling this transverse movement of the wheelsets, locomotives with rigid frames do not have to use the thinner wheel flanges etc. normally needed to facilitate smooth running through points, bends and tightly curved sections of track. The 'guide length' of the locomotive is formed by the distance between the two fixed Beugniot lever pivot points.
In Germany, Beugniot levers were used mainly in the middle of the 20th century. The best known examples of locomotives that use this type of lever are the MaK
Mak
Mak is a Chinese surname. It is commonly transliterated as Mak in Hong Kong, based on the Cantonese pronunciation of the Chinese character; and is commonly transliterated as Mai in China, based on the Mandarin pronunciation. Other transliterations of the surname include Mack, Mark, Mac, and Mach...
side-rod drive locomotives, the Class 105 and 106 engines in East Germany as well as steam locomotives like the DB Class 82
DB Class 82
The DB Class 82 was a goods train tank locomotive with the Deutsche Bundesbahn in Germany, that was built in the period after the Second World War and was intended for shunting and normal rail services...
.
Sources
Bedienungs- und Wartungsanleitungen der MaKMaschinenbau Kiel
Maschinenbau Kiel GmbH designed, manufactured and marketed marine diesel engines, diesel locomotives and tracked vehicles under the MaK brand name. The three primary operating divisions of Maschinenbau Kiel GmbH were sold to different companies in the 1990s.Rheinmetall acquired the military...
-Baureihen 600 D, 650 D und 1200 D