Abstract: A train control system is for a train comprising at least first and second train segments including a brake pipe being separated between adjacent train segments. The train control system preferably comprises a first control subsystem for installation in a locomotive of the first train segment and a second control subsystem for installation in a locomotive of the second train segment. The first and second control subsystems communicate with one another for controlling train braking. The system also preferably includes a third control subsystem for installation in a railcar adjacent an end of the first train segment. This third control subsystem preferably includes at least one pressure transducer for sensing brake pipe pressure adjacent the end of the first train segment, and at least one control valve for controlling brake pipe pressure adjacent the end of the first train segment.

Abstract: The cab signal and rail navigation systems of a railway locomotive are combined to form a single integrated system capable of acting as an automatic train protection system. The train travels along a railway route equipped with a wayside signaling system that features a multiplicity of wayside signal devices. Each wayside signal device provides to the cab signal system a cab signal inclusive of signal aspect information as to how the train should proceed along a particular segment of the railway route. When the train is traveling on a segment of track from which the cab signal is available, the cab signal system receives the cab signal via the AC track circuit disposed on the rails as the train approaches each wayside signal device. After filtering and decoding the electrical cab signal, the cab signal system communicates the deciphered signal aspect information to the rail navigation system.

Abstract: A transportation safety apparatus and method for the detection of obstacles which lie off the line-of-sight or beyond the field of view of a moving vehicle entails shooting a laser beam through the air from a moving vehicle, capturing the beam and passing it to a fiberoptic relay which transmits a laser pulse to a distant site, and receiving a reflection thereof if the site is clear of obstacles. The pulses are received within about 10-20 microseconds per kilometer of relay length from the time of launching, permitting monitoring of the probe-site in real-time.

Abstract: A railway car retarder mechanism that employs linear electromagnetic induction to precisely accelerate or decelerate a railcar. The retarder mechanism includes a plurality of linear induction stators having a spaced plurality of primary inductors, a controllable power source electrically connected with selected ones of the primary inductors, a controller for controlling the electric current transmitted to the respective primary inductors by the controllable power source, and a sensor for sensing selected railcar parameters and transmitting those parameters to the controller, so that the speed-corrective forces applied by the retarder are proportional to these parameters. The controller regulates the magnetomotive force which is imparted upon a selected one of a plurality of railcar wheel sets, and is connected with each controllable power source. In some embodiments, the sensor include at least a portion of fiber-optic cable, which cable can be disposed proximate to a predetermined length of track rail.

Abstract: A method bridges gaps in a power supply for electrical, converter-fed rail vehicles having front and rear ends with front and rear current collectors, as seen in a travel direction, for making contact with the power supply. The method includes switching a traction converter from a traction mode to a regenerative braking mode, that is to say a generator operation or from a braking mode to the regenerative braking mode. The switching takes place over a period during which the rail vehicle travels a distance. If possible, the distance is only slightly shorter than a distance between the front and rear current collectors. This occurs as soon as the front current collector is not in contact with the power supply.

Abstract: A method and device for effecting a fast but smooth deceleration or stopping of trains controlled under the automatic train control (ATC) system. Under ATC, a permitted maximum velocity is provided as an "ATC condition" to activate the brake system of the train if that velocity is exceeded. When it is necessary to alter the velocity of a train, a control center specifies a feeder section to have the ATC condition to be altered. Next, a substation corresponding to the specified feeder section is provided with notice about the alteration of the ATC condition. The notice includes the impending reduction of velocity. In response, the substation decelerates the train without using the ATC brake system provided on the train. When the train has been sufficiently slowed down such that the alteration of the ATC condition will not result in activation of the ATC brake system, the alteration of the ATC condition is then effected.

Abstract: In an electrical propulsion system on board a moving traction vehicle (such as a rapid transit rail car) having current collectors in contact with an energized third rail, controllable switch means is used to connect the system to the current collectors. From time to time the current collectors traverse gaps between adjacent sections of the third rail, in which event regenerative braking operation of the system will be prevented unless the next third rail section is energized by a wayside source of voltage. The switch means comprises the parallel combination of a diode that conducts current when the system is operating in a motoring mode and a reversely-poled thyristor that conducts regenerative braking current once a firing signal is applied thereto.

Abstract: An electric propulsion system for a traction vehicle includes a controllable power converter operable in either a propulsion or an electric braking mode in which power is withdrawn from a wayside source or returned to the source, respectively. The wayside source utilizes certain preselected frequencies for power generation and for signaling. It is desirable to detect these frequencies quickly and to be able to disconnect the vehicle from the source if some frequencies are being generated by the vehicle and others are not present on the system. Bandpass filters are coupled to the power converter to detect the preselected frequencies. Wayside transients sometimes encroach on these frequencies with large power spikes causing ringing of the filter circuits and delay in detecting the preselected frequencies. The system includes an active power limiter for limiting the peak amplitude of the signals coupled to the filters without interfering with the signal frequency content or affecting filter operation.

Abstract: A brake and/or propulsion command arrangement for railway vehicles, especially for abnormality detection of a dual brake system having a cam controller for producing ON-OFF control signals.The abnormal detection system employs a comparing circuit for comparing the control signals, an interlocking circuit for producing a verification signal of the position of the cam controlling, and evaluating circuit for producing a trouble detection signal when the control signals are unmatched and during the presence of the verification signal.

Abstract: A jerk controlled brake system having a malfunction detecting arrangement for suppressing a malfunction signal due to a normal difference between the jerk control circuit input brake command and the output jerk modified command signal for a time period at least sufficient to allow the delayed jerk modified command signal to match the input brake command signal. The timer circuit controlling this time period is resettable prior to expiration of the preset time period to provide an extended time period, when the brake command signal is repeatedly changed at time intervals less than the preset time period.

Abstract: An acceleration servo control system for railroad car retarders in which a computed desired instantaneous deceleration signal and a measured actual deceleration signal are compared and any resulting error signal is fed back through the servo network to adjust retarder braking pressures to achieve and/or hold the desired deceleration rate which will allow the cut of cars to leave the retarder at a selected speed. The desired instantaneous deceleration is computed using an algorithm incorporating actual measured speed, the selected exit speed, the number of axles in the retarder, and the remaining distance-to-go for all axles of the cut over which retarder braking will be effective, and based on the principle of braking each axle-wheel unit throughout the entire retarder length.

Abstract: The track brake is intended to limit the speed of rolling motion of a freight car according to the track gradient in a marshalling yard. A retarder installed along a braking rail comprises a number of braking tappets each having a portion which projects above the braking rail in the rest position and each being applied in turn beneath each wheel of the car to be braked. The track brake comprises a motion converter constituted by a series of rockers each pivotally mounted on a pin connected to the braking rail. One portion of each rocker cooperates with a braking tappet and another portion of the rocker cooperates with a piston-rod of a substantially horizontal hydraulic brake cylinder.

Abstract: A plurality of sensors, each generating distinct signals in response to the passage of leading and trailing edges of car wheels, are positioned along the rail at a height above the rail to detect the passage of a selected chord on the wheel tread. The distances between initial sensors and the final unit equal the various selected chord lengths on conventional sized wheels. When one of the initial sensors detects the passage of the trailing edge of the wheel at the chord level simultaneously with the detection of the leading edge of that wheel by the last unit, the output signals are applied to a logic circuit, which registers a wheel of corresponding diameter. Additional sensors placed immediately adjacent the final sensor provide measurement of actual wheel diameters slightly less than the standard sizes due to wheel wear.

Abstract: The velocity of a railway car travelling along a particular track can be determined by measuring the distance travelled by the car during a predetermined time interval. This distance travelled is measured by determining the location of the car with respect to a fixed point on the track at two different points of time. The determination of the location, in turn, is found by measuring the time period that it takes an electric signal applied at a fixed signal generating point to travel along the railway track and, once reaching the car, to be reflected back along the track to the signal generating point. By measuring the time delay between the applied signal and the reflected signal, the distance between the application point and the closest railway car on the track can be measured.

Abstract: An apparatus for measuring velocity of a bullet is shown. A portable clamping device securely holds the barrel of a gun in position during firing. A bullet fired from the gun is projected through two openings located a predetermined distance apart from the end of the gun barrel. The bullet passing through the first opening activates a timing circuit to start current flow through a measuring device. The bullet passing through the second opening stops the current flow through the measuring device. The measuring devices gives an output indication that is indirectly proportionate to velocity of the bullet with units indicating the speed of the bullet. The measuring device may be a ballistic meter with no return springs on a meter movement to remain in its maximum position after measuring current flow therethrough.

Abstract: Railway braking apparatus for frictionally engaging and retarding the wheels of railroad cars which includes a series of pneumatic cylindrical operators located between two adjacent crossties along the trackway. The piston of each pneumatic cylindrical operator is coupled to a frictional braking bar through a mechanical advantage pivotal lever. Each lever is pivotally connected to a rigid welded frame assembly including apertured lugs and pivot pins. The rigid force absorbing frame assembly is carried by the two adjacent crossties and includes a crosspiece member to which the cylinder of each pneumatic cylindrical operator is pivotally connected. The pivotal lever is constructed of a plurality of plates, two bolt accommodating tubes and a series of filler plates or slotted shims which allow for the lateral adjustment of the frictional braking bars and permits quick and easy assembly and dismantling of the actuators, levers and braking bar.

Abstract: This invention relates to a method and apparatus for determining whether or not a freight car in a classification yard can be adequately retarded, prior to it being moved to make up a freight train, by measuring whether the wheels of the freight car are too slippery for the car to be properly retarded to a safe speed while being moved toward the freight train.

Abstract: This disclosure relates to a predictor for determining the coefficient of friction existing between the rotating wheels of moving railway vehicles and the brake shoes of a pair of brake elements prior to the humping operation in a classification. One of the brake elements is slidably mounted to move longitudinally relative to the track rail when engaged by the rotating wheels of the railway vehicle. The kinetic energy or force imparted to the slidable brake element is transposed in fluid pressure by a pressurized responsive transducer. The fluid pressure is sensed by a measuring device which activates an alarm when the wheels of the railway vehicle are dirty or contaminated by unctuous material to permit the vehicle to be diverted to a sidetrack for special handling.