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Electric locomotives were first used on the London Underground when the first deep-level tube line, the City and South London Railway (C&SLR), was opened in 1890. The first underground railways in London, the Metropolitan Railway (MR) and the District Railway (DR), used specially built steam locomotives to haul their trains through shallow tunnels which had many ventilation openings to allow steam and smoke to clear from the tunnels. It was impractical to use steam locomotives in the small unvented tubular tunnels of the deep-level lines, and the only options were rope haulage (as on the Glasgow Underground) or electric locomotives. The C&SLR was opened just a few years after the very first use of electricity to drive rail vehicles (trains or trams) and the primitive locomotives reflected this. Over the next 15 years, motors became smaller, gear drives and motor suspension were developed and reliable multiple unit control became available. Electric multiple unit trains became the standard, but electric locomotives were still being built. From 1903, the MR and the DR began to electrify the central parts of their lines for use by electric multiple units (EMUs). On both railways carriages were hauled by electric locomotives that were exchanged for a steam engine to run over un-electrified distant sections. The last steam-hauled passenger trains were replaced in 1961. When not hauling passenger trains, the electric locomotives were used for shunting and for hauling departmental trains. Some locomotives, as on the MR, were retained just for these duties. Rather than buy additional locomotive for this work, as was required with the battery-electric locomotives, makeshift locomotives were created from withdrawn passenger vehicles of at least three types, which were modified to haul trains over any part of the system or shunt rolling stock at Acton Works. ==City & South London Railway== When the City & South London Railway (C&SLR) was authorised in 1884, it was intended to be a cable-hauled line, but during the construction phase, the promotors decided to use electric traction, despite the fact that the technology was in its infancy. Two prototype locomotives were built by Mather & Platt in 1889, to a design by Dr Edward Hopkinson, with Beyer-Peacock supplying many of the mechanical parts. No. 1 used motors mounted directly on the drive axles, while No. 2 had motors driven through gears. Trials were conducted in December 1889 with No. 1 and two passenger cars. No. 2 was also used for testing, but it is not clear whether it pulled any cars. A production run of 14 locomotives was then built, numbered 1 to 14, duplicating the original numbers 1 and 2. Each had four wheels, with Edison-Hopkinson motors fitted to the axles, which were permanently wired in series. A 26-step rheostat was used to control the speed, and a switch which altered the connections to the armature was used to reverse the direction of travel. The locomotives were small and short to fit within the small diameter tunnels, which were at the northern end of the railway, and on the straighter southern section, to allow higher speeds. The cab was built along the centre line of the locomotive with a door at each end and the controls and equipment mounted on the sides. There was a single driving position at one end of the locomotive with the power controller on one side and the Westinghouse air-brake valve and hand-brake column on the other. The controls worked directly so no form of multiple-unit control was ever possible. Each locomotive could haul three coaches at up to on good track, providing a service speed of around . At the end of a run, the arriving locomotive was trapped in the platform by its carriages. A replacement locomotive hauled the train away on the next trip and the released locomotive was then available to head the next incoming train (this is called "slip working").〔 The train air-braking system, controlled by the driver, was fed from an air reservoir on the locomotive and, as the original locomotives were unable to generate their own compressed air, the reservoirs were recharged at Stockwell Station from an air line maintained at .〔 Later, locomotives were fitted with compressors. The railway was opened on 4 November 1890 by The Prince of Wales (later King Edward VII) and locomotive No. 10 carried a commemorative nameplate with the name ''Princess of Wales'' to celebrate its use on that occasion. There was soon a need for an additional two locomotives to operate the service. Nos. 15 and 16 were built by Siemens with a modified design of motor, which attempted to overcome the problem of burnt-out armatures that had plagued the line since its opening. In 1895, the C&SLR itself built locomotive No. 17 at Stockwell depot, and carried out a series of tests on locomotives 12, 15 and 17, as more locomotives would soon be needed for the extensions being made. They ordered three more locomotives from different manufacturers in 1898, which were equipped with four-pole motors, a more efficient control system using series-parallel switching of the motors, and on-board compressors. The motors were still mounted on the axles. Another two locomotives (Nos. 21 and 22), which were built at Stockwell Depot, included further refinements and were the prototypes for the final batches of locomotives. Nos. 23 to 52 were built by Crompton to an improved design, including nose-suspended motors connected to the axles by a single reduction gear, but still bore a strong external resemblance to the original locomotives. Between 1904 and 1907, locomotives Nos. 3 to 12 were rebuilt with new electrical equipment to improve their performance. Following the introduction of new locomotives and the abandonment of the restrictive King William Street terminus in 1900, the C&SLR was able to run trains with four cars. Five-car trains were introduced from 1907. Six-carriage trains were briefly operated in 1914/15 and from October 1923 before the last part of the line was closed for reconstruction and tunnel enlargement in November 1923. The enlarged tunnels allowed the locomotive hauled trains to be replaced by 'Standard' Stock electrical multiple units. 44 locomotives were in use just before the closure and some remained in service until 1925 hauling works trains while the tunnels were being enlarged.〔 One locomotive survives in preservation. It was originally displayed as No.1, but investigations over a number of years finally identified it as either No. 13 or 14, and suggested that it was more likely to be No. 13 (the number which it now carries). After being displayed in the Science Museum,〔 it was transferred to the Acton store of the London Transport Museum, and then to the newly reopened museum in Covent Garden. No. 36 was displayed on a plinth at Moorgate Metropolitan line station for many years but was damaged beyond repair by a bomb in 1940. Some of its electrical parts were presented to Crompton Parkinson before the rest of it was scrapped.〔 A motor and axle from No. 36 are now held by the Science Museum but are currently in store. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「London Underground electric locomotives」の詳細全文を読む スポンサード リンク
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