DRG Class Kö I

The Kleinlokomotiven (literally: small locomotives) of Class I were light German locomotives of low weight and power (up to 40 PS) designed for shunting duties. They were placed in service by the Deutsche Reichsbahn (DRG) after trials had been carried out on several prototype locomotives in 1930. The power source for these locomotives was either a diesel or petrol engine.

After the Deutsche Reichsbahn had initially obtained several trials locomotives in 1930, it took delivery of production Kleinloks in 1931 and split them into two classes or 'power groups'. Locomotives in power group I, with an engine power of up to 40 PS (29 kW), were intended for shunting at small stations and in simple situations.

As a result of the new numbering scheme two of the trials engines from 1930 were also included in Class I. These were locomotives V 6016 and V 6017 (from 1931 Kö 0001 and Kö 0002) delivered by the Fürst-Stolberg-Hütte works at Ilsenburg. They did not acquit themselves well due to numerous defects and were retired again by 1932. Whilst, as early as 1931, the DRG had issued several specifications for locomotives in Class II, for Class I it simply ordered locomotives of the manufacturer's designs between 1931 and 1934, in order to keep procurement costs down. These locomotives were delivered by Jung, Orenstein & Koppel, Windhoff and Gmeinder. They were not permitted to leave the station, because they were too light to achieve reliable rail contact.

Once it had been demonstrated that the employment of low power Class I locomotives was economical, the project team developed a standard, small locomotive (Einheitskleinlokomotive) for the DRG. This was heavily based on the latest delivery from Gmeinder. As a result, the entire locomotive, apart from the diesel engine, was standardised. The footplate on the locomotives was open at the sides and all controls were duplicated on both sides of the engine. The Kleinlokomotiven had buffers and a very simple shunting coupling, that could be automatically coupled and then released using a foot pedal. Transmission was achieved from the engine using simple roller chains on both axles.

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Wikipedia