Matches 1 - 50 out of 190 1 2 3 4 >
Match Document Document Title
7296770 Electronic vital relay  
A railroad signaling method includes measuring a track current on a first track section, measuring a local voltage on the railroad line wires, determining whether a magnitude of the track current...
7269487 Method for train positioning  
In the state that a train moves from a track circuit 3 T toward a track circuit 5 T, and a train detection signal TD 1 is supplied from the boundary between the track circuits 3 T and 5 T to...
7027897 Apparatus and method for suppressing mechanical resonance in a mass transit vehicle  
A mass transit vehicle traction motor control system includes an automatic control block for receiving and processing a tachometer signal having a first resonance signal superimposed thereon to...
7017864 Railway track circuits  
Railway track circuit apparatus for train detection comprises a track circuit transmitter and a receiver, wherein the transmitter generates a QPSK modulated signal that is transmitted into a track...
6779761 Broken rail detection  
A break in a rail, where two rails ( 12, 13 ) extend parallel to each other along a railway line, is detected by connecting the two rails together electrically with two electrical connections ( 16,...
6494409 Railway code following apparatus  
A solid state code following track relay receives pulsating rail current from a railway code transmitter. The track relay includes first and second inputs structured to receive the rail current....
6102340 Broken rail detection system and method  
This invention relates to a system and method of detecting a broken rail in a railway system. The track sensing circuitry of the present invention applies a voltage source at each end of a block of...
5924652 Island presence detected  
A reliable and consistent electrical contact path between the rails of a section of railroad track established by the shunting effect of the wheels and axles of a train is ensured by applying...
5752677 Block occupancy detector for model railroads  
This invention pertains to model railroads and specifically to the problem of detecting the presence or absence of cars, locomotives, or obstructions which may occupy a particular section of track....
5720454 Audiofrequency track circuit with data transmission (digital TC); transceiver interface  
A track circuit is used in a railway plant or the like, and comprises a track segment which is isolated electrically from the adjacent segments by electrical splices which consist of a conductor...
5711497 Cab signaling apparatus and method  
The invention provides for a cab signaling apparatus and method for use on board a railway vehicle propelled on a set of spaced rails by a traction motor. The cab signaling apparatus may reduce a...
5680054 Broken rail position detection using ballast electrical property measurement  
The position of a break in at least one of a pair of rails in an electrically isolated rail segment of a railroad is carried out by measuring current across the ballast between the rails of the...
5470034 Railway track circuits  
This invention relates to railway track circuits. An active track circuit termination unit (4) is connected to the rails and, via a transmitter unit (4a), transmits signals into the rails to...
5358202 Cab signal track code analyzer system  
A track code analyzer is disclosed that measures the duty cycle, carrier frequency, modulation frequency, and amplitude of track code signal and determines when these parameters are outside...
5331288 Railroad rail signal receiver having frequency conversion and a resonant tuned transformer secondary  
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...
5330135 Railway track circuits  
A railway track circuit system is described, in which there is a transmitter 15,16 and receiver 19,20 at each end of a track circuit section 4. Each receiver receives signals from the transmitter...
5330134 Railway cab signal  
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...
5242136 Railway signalling systems  
A railway signalling system for the detection of a train within a defined section of track by means of track circuit apparatus utilizes the rails within the section as part of the track circuit....
5234184 Locomotive axle mounted cab signaling sensor  
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...
5219426 Single-element coded alternating current railway track circuit having double-element, phase-selective capability  
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...
5170970 Method and apparatus for improving rail shunts  
A reliable and consistent electrical contact path between the rails of a railroad track established by the shunting effect of the wheels and axles of a train is ensured by applying an alternating...
5145131 Master-Satellite railway track circuit  
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...
5094413 Device for the protection of track relays from electrical disturbances  
A device for protecting track relays from electrical disturbances originating from a train's traction current. The device has: a control signal generator; a signal inverter, to invert periodically...
5029780 Multi-frequency railroad grade crossing termination shunt assembly  
A multi-frequency shunt is provided for use between the rails of a railroad track to define the approach distance for a railroad crossing using a constant warning time or motion detection device....
4984521 Conveyor control  
The invention is a conveyor control system having self-propelled vehicles having wheels, each driven by a motor (14) to move along rails. The system includes power rails (18) for supplying power to...
4979392 Railroad track fault detector  
A railroad track fault detector is mounted on a tracked vehicle and uses the track ahead or behind the vehicle as a transmission line for a high frequency signal. The transmission line has a known...
4932614 Train communication system  
A communication system for a railway train has a proving circuit for proving conditions of the railway track ahead of the train. The proving circuit comprises a transponder associated with at least...
4886226 Broken rail and/or broken rail joint bar detection  
The apparatus of this invention is a broken rail detection system that detects rail and/or rail breaks in dark territory track sections, i.e. track sections that do not have signalling systems. In...
4742460 Vehicle protection system  
An automatic vehicle protection system, e.g. for a railway vehicle, in which continuous contact is maintained with a train via transmissions carried by the normal track circuit signals. Information...
4732355 Rate code decoding system  
In railway signaling systems which transmit rate code signals along track circuits, which signals are picked up by the trains and used for signaling purposes, such as speed control, the rate code...
4728063 Railway signalling system especially for broken rail detection  
Broken rail detection in a block of track without the need or expense of conventional signalling uses a chain of transmitters and receivers connected to the rails and defining sections of the block...
4723739 Synchronous rectification track circuit  
An improved audio frequency track circuit system utilizes a synchronous train detection arrangement and reduces the number of fixed code rate modulated carrier signals. As few as two carrier...
4619425 Pulse code system for railroad track circuits  
An alternating current code, alternately transmitted in each direction through the rails of a railroad track section, includes a selected number of pulses of alternately positive and negative...
4575031 Device for detecting the unbalance between the two fractions of the return traction current in the rails of a railroad track  
A device for detecting the unbalance Δi between the two fractions of the return traction current flowing in the two rails of a railroad track, in the presence of a signalling current in the...
4570882 Vital track circuit wheel detector  
A vital, or fail-safe, track circuit wheel detector for detecting the presence and position in a given detection zone of wheel-axles on railroad cars; in order to provide the requisite fail-safe...
4535959 Vital solid state relay for railroad alternating current track circuits  
This vital solid state relay incorporates only passive elements and is intended for use as a replacement for a two element AC track relay in AC track circuits. The local input signal is applied to...
4516249 Railway signalling receiver  
A railway signalling receiver in which a signal carried by the railway lines is sensed and the sensed signal is sampled, digitized and subjected to a discrete Fourier transform operation which...
4498650 Microprocessor based track circuit for occupancy detection and bidirectional code communication  
A railroad train detector and communication system relies on the track rails for communicating information among a plurality of locations. The equipment located at each of the locations eliminates...
4487385 Method of controlling a railroad car in automatic drive  
A voltage variation detector is connected to a receiver which is associated with a transmitter inducing an alternating signal permanently in the rails of a railroad track and, accordingly, in a...
4451018 Non contact isolated current detector  
A receiver for sensing track currents includes a toroid coupled to the track rails via a single conductor. The toroid has an air gap in which a linear Hall sensor is inserted. The voltage of the...
4442988 Information transmission device through the rails between a railway track and a vehicle assembly circulating on this track  
An improvement in apparatus for the secure transmission of information through rails in zones of propagation independent from the sections of the track block-section system embodying the use of...
4437632 Reset apparatus for railroad track circuits  
The two inputs of a first flip-flop (FF) are alternately energized over a pair of opposite contacts of a code transmitter. Outputs of a second FF alternately enable a pair of logic gates to pass...
4415134 Hall effect track circuit receiving element  
A railroad signal circuit includes a transmitter and a receiver which have a common connection to the track rails at one end of a signal block. There will be a similar transmitter and receiver at...
4407470 Code reset apparatus for railroad track circuits  
Coded energy applied to the track circuit rails for cab signal control when a train occupies the section is also applied over a line circuit to the local input of the solid state track relay unit...
4392626 Vital protection arrangement for railroad track circuits  
A tuned transformer element has its primary winding coupled, in series with a fuse of preselected rating, to the rails of the track circuit. A secondary winding supplies input energy to the track...
4373691 Decoupling arrangement for non-insulated AC track circuits in railway systems  
A decoupling arrangement for non-insulated track circuits is disclosed wherein the receiving circuit of the evaluating unit for the AC track currents is electrically separated from the...
4369942 Signal control system  
A railroad signal system includes an A type transmitter and receiver for sending and receiving signal messages in one direction and a B type transmitter and receiver for sending and receiving...
4361301 Vehicle train tracking apparatus and method  
A vehicle train tracking apparatus and method are provided for responding to detected occupancies and unoccupancies of each of a plurality of signal blocks of a roadway track system to establish a...
4352475 Audio frequency track circuit for rapid transit applications with signal modulation security  
An audio frequency track circuit with improved security in the train detection function for rapid transit applications for use with uninsulated rails includes an improved transmitter and receiver....
4349170 Safety coding process for track circuits  
A process for coding track circuits allows particularly information to be transmitted to a vehicle travelling over a railway track divided into a succession of sections each equipped with a track...
Matches 1 - 50 out of 190 1 2 3 4 >