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Link & Pin Couplers
Link & Pin Coupler

Link & Pin Coupler, Hart #234Link & Pin Coupler, Hart #319

Link & Pin Coupler, CP*RR Link

Link & Pin Coupler, Pins, Hart #319

Link & Pin Coupler, Links, Hart #234

Link & Pin Coupler, Diagram

Courtesy Bruce C. Cooper Collection.

Images courtesy of:

Link and pin coupler designs (as used by the Central Pacific and Union Pacific Railroads and shown above) were being obsoleted between 1870 and 1885. Andrew Dow notes* that "the ICC Annual Statistics for 1893, ... lists 55 types of coupler in use on American railroads ... [and] fifteen 'kinds' of brakes in use by the railroads. It was indeed an age of invention, and I am sure that anyone with the leisure and opportunity to examine the records of the Master Car Builders' Association (a set is in Library of Congress) will find a full account of work done to achieve standardisation – Janney [Coupler] and Westinghouse [Air Brake] won, as we all know." Wendell Huffman observes* that "the 19th century was a wonderful time for inventors and that there was nothing like standardization from road to road." Tom De Fazio notes* that "according to Norman Carlisle (The Modern Wonder Book of Trains and Railroading, John C. Winston Co., Philadelphia & Toronto, 1946), there are more than (more than) 10,000 patents addressing the link and pin coupler alone; that more than (more than) 1,000 of them were adopted by one or another railroad." "In 1887, the Master Car Builders Association selected the Janney Automatic Coupler, invented by Eli H. Janney in 1873, over 40 other designs as a standard design for the railroad industry. On March 3, 1893, President Benjamin Harrison signed the Safety Appliance Act, which made automatic couplers and air brakes mandatory on all trains."

Dick Dawson comments* that "When I was writing the section on couplers, draft gears and hydraulic cushioning devices for the 1997 Car & Locomotive Cyclopedia, I came across a reference to a manufacturer who advertised in the early 20th century the availability of 119 different designs of coupler knuckles. This reflected a key problem with the "standard" knuckle couplers then in use. When the Master Car Builders Association adopted in 1888 the coupling face contour lines of the 1879 Janney coupler patent, they ensured that all couplers built to the MCB standard would be able to couple with each other. They did not, however, standardize the dimensions of the various parts of the coupler - the knuckle, lock, interior of the coupler head, etc. Consequently, all cars equipped with MCB couplers could operate together, but maintenance of those cars in interchange became a real problem. When a car showed up at a repair track with a defective knuckle or coupler that the shop did not stock, the shop had two undesirable options - send the car home for repairs or wait for compatible parts to be shipped to the car. Consequently, the MCB Coupler Committee asked the coupler manufacturers in 1911 to cooperate with the Committee in the development of a coupler, all of whose parts would be interchangeable regardless of manufacturer. After reviewing nine submitted coupler designs, the MCB selected two, submitted by American Steel Foundries and National Malleable Castings, for further development. The revised National design, the Type D, was adopted as the new standard coupler in 1916. A licensing arrangement was developed by the coupler manufacturers under which all had access to each other's patents and all could produce the standard coupler and its parts. While the D coupler provided a number of benefits relative to prior couplers, such as greater strength, its primary benefit was the complete interchangeability of all parts. Further development led to a coupler which offered significant advantages relative to the Type D but whose parts could not be made interchangeable with those of the D. This became the Type E coupler which was adopted by the ARA (successor to the MCB and predecessor of the AAR) in 1930 and advanced to Standard in 1932. 74 years later, the Type E is still the most widely used coupler. Today's E couplers are improved in many respects, such as the use of higher grade steel, but the parts are still interchangeable with those of a 1930 coupler. Passenger cars now use interlocking couplers based on the AAR Type H and rotary dump cars use Type F interlocking couplers, but the vast majority of freight cars built today are equipped with Type E couplers with shank lengths appropriate to the car configuration."
*[from the R&LHS Newsgroup]

Eli H. Janney's 1873 U.S. Patent #138,405 for "Improvement of Car Couplings."

Eli H. Janey's Railroad Car Automatic Coupler U.S. Patent, 1873.

Eli H. Janey's Railroad Car Automatic Coupler U.S. Patent, 1873.

Eli H. Janey's Railroad Car Automatic Coupler U.S. Patent, 1873.

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