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The PCC (Presidents’ Conference Committee) streetcar (tram) design was first built in the United States in the 1930s. The design proved successful in its native country, and after World War II was licensed for use elsewhere in the world. The PCC car has proved to be a long-lasting icon of streetcar design, and PCC cars are still in service in various places around the world. == Origins == The "PCC" in this car's name comes from the name of a design committee formed in 1929 as the Presidents' Conference Committee and renamed the Electric Railway Presidents' Conference Committee (ERPCC) in 1931. This group's membership consisted mostly of representatives of some of the larger operators of urban electric street railways in the United States. Three interurban lines and at least one "heavy rail," or rapid transit, operator - the Chicago Rapid Transit Company - were represented as well. Also included on the membership roll were manufacturers of surface cars (streetcars) and interested component suppliers. The ERPCC goal was to design a new and modern type of streetcar that would better meet the needs of the street railways and their customers. The committee prepared a detailed research program, conducted extensive research, built and tested components, made necessary modifications, and, in the end, produced a set of specifications for a complete vehicle of a set design (albeit one with a modest list of available options and at least some room for customer customization) built with standard parts as opposed to a custom designed carbody with any variety of different parts added to it depending on the whims and requirements of the individual customer. The design patents resulting from the work of the ERPCC were transferred to a new business entity called the Transit Research Corporation (TRC) at the time of the committee's expiration in 1936. Although this company would continue the work of research on improvements to the basic design of the car and would issue sets of specifications three times in the ensuing years, because TRC defined a PCC car as any vehicle which utilized patents on which it collected royalties, it was formed for the primary purpose of controlling those patents and promoting the standardization envisioned by the ERPCC. The company was funded by its collection of patent royalties from the railways which bought PCC cars. The company was controlled by a voting trust representing the properties which had invested in the work of the ERPCC. Although a participant in Committee meetings, trolley manufacturer J. G. Brill and Company brought a competitive design—the Brilliner—to market in 1938. With Raymond Loewy designed elements, very similar to the PCC look, the Brilliner attracted no large orders, serving most conspicuously with Atlantic City Transit. Fewer than 50 were sold. A significant contribution to the PCC design was Noise Reduction with extensive use of rubber in springs and other components to prevent rattle, vibration, and thus noise and to provide a level of comfort not known before. Wheel tires were mounted between rubber sandwiches and were thus electrically isolated so that shunts were used to complete ground. Resilient wheels were used on most PCC cars with later heftier cousins known as Super-Resilient. Gears were another source of considerable noise, solved by employing hypoid gears which are mounted at a right angle to the axle, where three of the six teeth constantly engaged the main gear, reducing play and noise. All movable truck parts employed rubber for noise reduction as well. "Satisfactory Cushion Wheel of Vital Importance; Develop New Truck Design; Generous Use of Rubber" are headings within a paper that Chief Engineer Hirshfeld both presented and published.〔C.F.Hirshfeld, Ch.Engr., PCC; (October 1933) "Electric Transit and Bus Journal", pp.321–325, 331.〕 After a specification document suitable for purchasing cars was generated by TRC orders were placed by 8 companies in 1935 and 1936. First was Brooklyn & Queens Transit Co. (B&QT) for 100 cars, then Baltimore Transit Co. (BTCo) for 27 cars, Chicago Surface Lines (CSL) for 83 cars, Pittsburgh Railways Co. (PRCO) for 101 cars, San Diego Electric Railway (SDERy) for 25 cars, Los Angeles Railway (LARy) for 60 cars, and then Boston Elevated Railway (BERy) for 1 car. In late 1935 or early in 1936 Westinghouse Electric pressed for one car to be equipped with their electrical equipment for testing in Pittsburgh, since the Brooklyn order would have all cars equipped by General Electric, and Clark Equipment Co. pressed for one car to be made by them of aluminum for delivery to B&QT. Agreements among the parties were reached whereby St. Louis Car Co. would build 101 essentially identical cars and Clark would build one of its own body design. Brooklyn received its first car #1001 on May 28, 1936, PRCo took delivery of car #100 on July 26, 1936, and Baltimore received its first car on September 2, 1936. In the late 1936 discussions of operating experience it was noted that the Brooklyn car had run 3000 miles by the time the Pittsburgh car had run 1000 miles. The first car to be placed in a scheduled public service was PRCO #100 in August and B&QT launched its first scheduled service with a group of cars on October 1 of 1936, followed by CSL on November 13, 1936. Production continued in North America By St. Louis Car Co. and Pullman-Standard until 1952, with 4978 units being built. Under license to use the designs patented by TRC thousands more PCC and partially PCC type cars were produced in Europe through the last half of the 20th century. The cars were well-built and many hundreds are still in operation. The majority of large North American streetcar systems surviving after 1935 purchased PCC streetcars; those systems which eventually closed down streetcar operations often selling their cars to the surviving operators. Several dozen still remain in public transit service in Boston, Philadelphia, and San Francisco following extensive overhauling. All other surviving and functional North American PCC cars are operated by museums and heritage railways. 〔Proceedings of The American Transit Association, 1936, pp. 821, 822, 833, 834,1126,1127 & 1938 Proceedings, pp. 372, 374, 376, 378, 380, 382, 384, 408, 416, 417, 418, 420, 422, 380,382, 384, & An American Original, The PCC Car, Kashin and Demoro, pp 42,43,46, 187.〕 Washington, DC, PCCs were unique〔King, Leroy O., Jr., 100 Years of Capital Traction: The Story of Streetcars in the Nation's Capital. Dallas: Publisher Leroy O. King, Jr. (1972), page 153〕 because of conduit plows which collected current from a slot between the rails into which the plow dipped, contacting positive and negative rails under the street on either side. At the city limits were "plow pits", where the plow was dropped and removed, the trolley pole raised, and the car then continued on its way, utilizing overhead wire; the process was reversed in the opposite direction into Washington. "The PCC car was not just another modular vehicle but the result of the only systems engineering approach to mass producing a rail car."〔Carlson & Schneider (1980), p. 59.〕 Research into passenger comfort resulting from vibrations, acceleration, lighting, heating and cooling, seat spacing, cushion height, space for arms, legs, standing passengers, economies of weight affecting maintenance, cost of power, reduced wear of components and track. Dimensions were established to fit the majority but could easily be changed for special situations. Windows were spaced to match seating. While some of the components in the PCC car had been used before—resilient wheels, magnetic braking, sealed gears, and modular design to name a few—the ERPCC redesigned, refined, and perfected many of these while developing new acceleration and braking controls and put them all in one package. The PCC is far more than a good design, it is an excellent design with modern transit rail vehicles essentially upgrading the design with the most recent technology. 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「PCC streetcar」の詳細全文を読む スポンサード リンク
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