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For other uses, see Geeps (disambiguation). The EMD GP7 is a four-axle (B-B) road switcher diesel-electric locomotive built by General Motors Electro-Motive Division and General Motors Diesel between October, 1949 and May 1954.〔Pinkepank, Jerry A. (1973) pp. 53〕 Power was provided by an EMD 567B 16-cylinder engine which generated .〔The History of EMD Diesel Engines〕 The GP7 was offered both with and without control cabs, and those built without control cabs were called a GP7B. Five GP7B's were built between March and April 1953.〔 The GP7 was the first EMD road locomotive to use a hood unit design instead of a car-body design. This proved to be more efficient than the cab unit design as the hood unit cost less, had easier and cheaper maintenance, and had much better front and rear visibility for switching. Of the 2,734 GP7's built, 2,620 were for American railroads (including 5 GP7B units built for the Atchison, Topeka and Santa Fe Railway), 112 were built for Canadian railroads, and 2 were built for Mexican railroads. This was the first model in EMD's GP ''(General Purpose'') series of locomotives. Concurrently, EMD offered a six-axle (C-C) SD ''(Special Duty)'' locomotive, the SD7. == History == ALCO, Fairbanks-Morse, and Baldwin had all introduced road switchers before EMD, whose first attempt at the road-switcher, the BL2 was unsuccessful in the market, selling only 58 units in the 14 months it was in production.〔Pinkepank, Jerry A. (1973) p. 51〕 Its replacement, the GP7, swapped the truss-framed stressed car body for an un-stressed body on a frame made from flat, formed and rolled structural steel members and steel forgings welded into a single structure (a "weldment"), a basic design which is still being employed today. Unfortunately, in heavy service, the GP7’s frame would bow and sag over time.〔 This defect was corrected in later models. The GP7 proved very popular, and EMD was barely able to meet demand, even after opening a second assembly plant at Cleveland, Ohio. Later, locomotives in EMD's GP-series came to be nicknamed ‘Geeps’. Many GP7s can still be found in service today, although most Class 1 roads stopped using these locomotives by the early 1980s. 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「EMD GP7」の詳細全文を読む スポンサード リンク
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