This class includes patents relating to the following means for the safeguard and control of traffic upon or across railways (that is, fixed tracks for occupant- controlled vehicles) or which by structure are especially adapted for such use, viz:
A. Signals, including those used for communication between occupants of a car or train.
B. Indicators, recorders, telegraphic, telephonic, or other similar apparatus when especially designed for use in connection with car or train movements, except manually-set devices, such as train and engine signs and markers capable of general use.
C. Devices on the roadway, such as signals, switches, circuit closures, gates, etc., actuated or controlled from or by the moving vehicles, except circuit-controllers actuated by the vehicle for the purpose of energizing sectionalized conductors used for supplying propulsion-current thereto.
D. Automatic train stop and speed control means, the actuation of which is initiated by agencies not on the train or by wheel derailment or defects in train structure and mechanism, the automatic stop, for classification purposes, being considered an equivalent of and substitute for a railway signal; but train stopping and control mechanism cooperating with obstacles fixed in position upon the track which have no moving parts are excluded from this class except when they cooperate with speed-responsive devices on the train.
E. Safety devices, including derailing switches and blocks, used for preventing accidents caused by the misplacement of switches, disregard of signals etc.
F. The structure of signals, switches, frogs, and crossings and their appurtenances.
G. Mechanism for the manual or other actuation of any of the devices of the class.
INDEX TO TECHNICAL LITERATURE
In many of the subclasses there have been placed upon the official search-cards references to such literature as appears to relate to the subject-matter of such subclass; but no attempt has been made to make these references complete. It has not been deemed advisable to print these references in connection with the respective subclass definitions; but they can be inspected in the Public Search-Room in connection with the Chief Draftsman"s classified copies of patents. The list of works indexed is given below.
Literature in Scientific and Technical Information Center
Alternating Current Signaling, 1915, The Union Switch and Signal Co., Swissvale, Pa. Automatic Block Signal and Signal Circuits, Scott, New York, 1908. Block and Interlocking Signals, Elliott, New York,1896. Block System of Signaling on American Railroads, The, Adams, New York, 1901. First to Fifth Annual Reports Block Signal and Train Control Board, Interstate Commerce Commission,1909 to 1913. Locking, Laverack, New York, 1907. Mechanical Railway Signaling, second edition, Wilson, London, about 1909. Notes on Track Construction and Maintenance, Camp, Chicago, 1903. Perfect Railway Signaling, Spang, 1902. Power Railway Signaling, Wilson, 1908. Railroad Signal Dictionary, The, Adams & Hitt, New York, 1908. Railroad Signal Dictionary, The revised edition, New York, 1911. Railway Appliances, Barry, New York, 1896. Railway Block Signaling, Pigg, London. Railway Engineer, The, (about 1909). Railway Signal Association, Digest of Proceedings, Vol.1, 1895-1905; Vol.2, 1905; Vol.3, 1906; Vol.4, 1907; Vol.5, 1908; Vol.6, 1909. Railway Signal Association, Journal, 1910, Vol.XIII; 1911, Vol.XIV; 1912, Vol.XV; 1913, Vol.XVI; 1914, Vol.XVII; 1915, Vol.XVIII; 1916, Vol.XIX;1917, Vol.XX. Railway Signal Engineering, L. P. Lewis, London,1912. Railway Signaling, Pittsburgh, 1908. Railway Signaling in Theory and Practice, Latimer, Chicago, 1909. Railway Track and Track Work, Tratman, New York, 1908. Safe Railway Working, Stretton, 1886. Signal Engineer, The, 1908, Vol.1; 1909, Vol.2; 1910, Vol.3; 1911, Vol.4; 1912, Vol.5, 1913, Vol.6; 1914, Vol.7; 1915, Vol.8; 1916, Vol.9. Street Railway Road Bed, Pratt and Alden, New York, 1898.
Lines with other classes and within this class
MEANS PECULIAR TO SPECIAL TYPES OF RAILWAYS
Means peculiar to special types of railway, such as mono-rail, rack-rail, electric, pneumatic, logging, cash-carrier, elevated, cable, suspended, etc., and not of general utility or if claimed in connection with structure of such special types of railway will be found in the appropriate subclasses of other classes, for which see References to other Classes, below. But when such means are directed to the structure or operating mechanism of the switches of this class (246) subclass 415, they will be found in this class (246) subclass 419, indented thereunder.
SIGNALS AND INDICATORS IN OTHER CLASSES
For signals used for communication between occupants of a car or train see References to Other Classes, below.
For manually-set devices, such as train and engine signs, and markers capable of general use see references to Other Classes, below.
Where a semaphore is of the well known conventional railway type, (which is more fully described in the definition of subclass 479 of this class), the patent is classified here, but otherwise is some subclass of Class 116, Signals and Indicators, or Class 340, Communications: Electrical, unless claimed for railway use, in which case it is here classified.
SPEED CONTROL IN OTHER CLASSES
For speed control vehicles, when all of the mechanism is upon the vehicle and there is no cooperation with devices on the track or roadway, see References to Other Classes, below.
TRAIN STOPPING IN OTHER CLASSES
For train stopping and control mechanism cooperating with obstacles fixed in position upon the track which have no moving parts see References to Other Classes, below.
Closures (gates) when performing a stopping rather than a signalling function will be found elsewhere, except that railway-gates and mine-doors actuated by the energy of a moving vehicle or electrically controlled therefrom will be found in subclasses 125 and 292 of this class (246) and in the various subclasses indented thereunder.
For track structure other than as indicated above, see the Search Class references below.