Abstract: A railway track circuit system utilizing an optical sensor which emits a vehicle detection light signal when a railway vehicle is present in a track section. A reference light signal is also generated by a light emission source. A detector in optical communication with the optical sensor receives the vehicle detection light signal. Information contained in the vehicle detection light signal is interpreted by a processor to detect the railway vehicle. In presently preferred embodiments, the sensor may comprise an elongated optical fiber conductor extending along the track section or a plurality of cascaded localized sensors. The sensor may generally also be utilized as a communication medium to pass communication data between opposite ends of the track section. Depending on the exigencies of the particular application, the sensor may be located within the track section in a number of ways.

Abstract: A receiver for use in receipt of signals on railroad rails which converts the rail signal to a higher frequency and feeds the higher frequency signal into an input transformer. The secondary of the input transformer is in a tuned circuit which is resonate at the higher frequency and which contains a winding of an output transformer. The tuned circuit can be tuned to the higher frequency by series components such as a resistor and capacitor.

Abstract: An improved railway cab signal transmitter for transmitting a cab signal onto a pair of rails for reception by a railway vehicle on said rails. A tuning arrangement is connected across the rails to generally resonate with the leaving end impedance bond at a preselected cab signal frequency. The cab signal is coded at the preselected frequency such that the resonant circuit acts in conjunction with the code signal generation to act as a constant current signal source feeding the rails. A reduction in the maximum cab signal rail current is achieved thereby mitigating runby cab signal currents which might be available for reception by following trains. Embodiments of the tuning arrangement use a capacitor on the primary winding of the feed transformer. Other embodiments include inductance in series with a capacitor. Receivers for wayside displays that also use the cab signal current include embodiments having a capacitor or a capacitor/inductor across the wayside receiver transmitter secondary.

Abstract: A railroad interlocking control system utilizing a plurality of programmable controllers to regulate flow of train traffic through an interlocking track layout in which a number of track routes converge and overlap into a bottleneck area. Control of switch and signal devices in the bottleneck area is shared by multiple programmable controllers which may reduce redundancy requirements of prior art arrangements.

Abstract: A transmitter for transmitting cab signal and track signal currents to a pair of rails includes the circuitry for mitigating runby currents which are not fully shunted by the rail vehicle. High runby currents at the leaving end of a block are reduced by sensing the presence of a railway vehicle in the leaving end of the block. In response to sensing the rail vehicle the cab signal voltage is reduced to a lower level. The lower level and the position at which the railway vehicle is sensed are adjusted so as to permit a lead vehicle to receive at least a minimum cab signal value throughout its journey while assuring that following trains receive less than the minimum cab value required to activate the vehicle based receiver. The train is sensed by the voltage drop across the rails as the train approaches. A relay is used to respond to the presence of the train by applying a lower cab signal to the rails.

Abstract: A railway vehicle cab signalling system providing electrical signals to operate an aspect display unit or the like located on-board a railway vehicle based upon the track circuit signals typically used to operate wayside indicators. A sensor detects the track circuit current as it passes through at least one wheel and axle set on the vehicle. A processor receives an output signal from the sensor and produces a signal to operate the aspect display unit.

Abstract: A sensing device mounted on a railway locomotive vehicle axle assembly to sense signalling currents conducted through the axle. The device also serves to protect the critical traction motor support bearing from contamination by foreign substances. The sensing device includes a core member mounted in material at least partially covering the bearing and maintaining the core member in position encircling the axle. The core member conducts magnetic flux caused by the flow of current through the axle. An electrical conductor wound about the core member and/or a hall effect sensor embedded within the core member detect the presence of the flux. Clamping bands maintain the mounting material in position about the axle.

Abstract: A railway track circuit surge suppression system for the protection of wayside equipment from transitory energy surges appearing in the rails. The system has a primary surge suppression stage typically near the rails and a secondary surge suppression stage typically near the equipment to be protected. The secondary stage comprises an apparatus having a pair of inductors arranged serially with the respective track line wires to oppose the flow of surging current. Thus, the much of the energy dissipates at the primary stage. Remaining energy is dissipated by a voltage clamp behind the inductors.

Abstract: The invention provides a single-element coded alternating current railway track circuit which may be adapted to a double-element Phase-Selective configuration. A transmitter, via a transmitter transformer, provides a coded track signal to the track. A receiver transformer having one primary winding and a pair of secondary windings receives the track signal. One of the secondary windings is connected directly across a rectifier.The other secondary winding is connected in series with a secondary winding of a local transformer. This serial combination is electrically connected across another rectifier. A DC code-following relay is electrically connected across a rectified output of the first rectifier via two output terminals. A third output terminal allows substitution of a magnetic stick relay for the code-following relay if a double-element configuration is desired. The primary winding of the local transformer has terminals for connecting an AC source when using the optional double-element configuration.

Abstract: A mounting arrangement for clamping telemetering monitoring equipment to the core holes of a railroad car coupler including a mechanical assemblage having a pair of fingers which are insertable into the core holes. A tightening mechanism including rotatable threaded rod engages a pivotal gripping block which contacts a web portion between the core holes to draw the outer surfaces of the fingers tightly against the inner surface of the web portion to rigidly hold the assemblage in place.

Abstract: A railway track circuit for protection of an extended track block having a master unit at one end of the block and a satellite unit at the other. Each master and satellite unit having transmitting and receiving capabilities. The output impedance of the transmitters or of the receivers is of a low impedance as connected to the rails. Through an alternative transmit and receive sequence a link-up between the master and satellite units provides detection of broken rail and/or shunts from each end of the track circuit. The use of low impedance and detection at both ends of the section permit extended length track circuits.

Abstract: A clamping arrangement for securing end-of-train sensing and monitoring equipment to a railway car coupler and including a plurality of movable gripping arms. A rotatable elongated threaded screw cooperatively associated with the movable gripping arms. The movable gripping arms include insertable portions which fit into core holes formed on the side of the car coupler and which securely grip the sides of the core holes when the gripping arms are closed by the threaded screw.

Abstract: A braking distance verification system is disclosed which makes use of a specially designed pulse to voltage converter circuit and a portable computer-based data acquisition system to measure grade, speed, and distance information of any rail vehicle. The preferred embodiment of the device is particularly adapted for mass transit systems. It provides a method and apparatus for physical verification, under actual test conditions, that an adequate braking distance has been provided in each block of a signal block design system. The portable system may be used with any vehicle braking system which provides an electronic wheel tachometer or equivalent, or may utilize a portable doppler radar if tachometer information is not available.

Abstract: The circuit arrangement of this invention includes a signal searchlight wherein the lamp is in an electrical series circuit with interlock contact switches. The switches interlock the display color lens such as yellow and green to control the electrical energization of the signal circuit. Logic control switching devices in a remote wayside control box supply signals through a cable to operate a bipolar device to selectively display the desired color.