General Signal Corporation

Other

Klaus H Frielinghaus

Barry L Smith

John H Auer, Jr

James R Hoelscher

Frank A Raso

Clinton S Wilcox

Gary E Clark

Zalmai S Shahbaz

A 4-terminal resistor apparatus which includes a body of resistive material having opposed first and second ends and opposite first and second sides. The distance between the opposed ends is no greater than the distance minimum width of the body intermediate opposed ends. Preferably, the width is 3 or 4 times greater than the distance intermediate the opposed ends. The first and second ends have respective first and second metal contact surfaces disposed thereon. The first and second pairs of leads each include first and second leads, each pair of leads engages one of the metal contact surfaces. The apparatus also includes means for holding the leads in each of the pairs of leads apart even if one of the leads in a given pair should become detached from the body of resistive material. In many forms of the invention the body is disc shaped.

Four terminal safety resistor

A technique for measuring the insulation resistance of an insulated rail joint in the presence of leakage ground resistance (ballast resistance), as well as other track run-around paths, without the use of calibrated meters, such technique characterized by the use of a bridge circuit which includes a leg having the insulated joint therein whose resistance is being measured, the other three legs including a resistor of fixed known value and two variable resistors respectively, such that when the variable resistors are varied to obtain simultaneously both (a) the null of the rail, or ballast, current, and (b) ballast in the bridge circuit, the resistance value of the insulated joint is determined.

Apparatus and method for measuring insulated track joint resistances

A relay apparatus which comprises an armature, means for pivotally mounting the armature, first and second pole pieces dimensioned, configured and disposed for cooperation with the armature, a magnetic circuit including at least one coil, a plurality of iron shunt lamina spanning the magnetic circuit intermediate at least one of the coil and the first and second pole pieces, and a plurality of copper washer slugs in the magnetic circuit intermediate at least one of the first and second pole pieces and the iron shunt lamina. The invention also includes a method of immunizing a relay from alternating current.

Alternating current immunized relay and method of immunizing a relay to

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 one embodiment of this invention a system is disclosed in which a communications link exists between the ends of the track sections and in another embodiment of this invention no communications link exists between the ends of the track sections.

Broken rail and/or broken rail joint bar detection

An audio frequency (AF) track circuit whereby a railway track tuned loop transmitter operating in a dual resonant mode, for handling, two signal frequencies, can be coupled to the rails. Each frequency is conducted through a tuning unit having series and parallel branches tuned to each frequency. The track circuit using the tuned loop transmitter eliminates DC return current imbalance effects while maintaining suitably high track circuit shunting sensitivity.

Combination frequency loop coupling for railway track signalling

A railway wheel detector which is mechanically actuated by the flange of a railway wheel which engages a contacting surface of the detector which may be provided by a rigid plate. This surface is supported by blocks of compressible, resilient material, preferably a closed cell foam elastomeric material, which has more stiffness in a vertical direction than in a longitudinal direction (the direction along the railway track) so as to transmit forces for actuating the plunger of an electrical switch mechanism when the flange of the railway wheel contacts the contacting surface, but allows the contacting surface to move with the wheel to avoid wear, thereby providing reliable operation over a long life time. The switch is preferably hermetically sealed and the blocks of compressible, resilient material are preferably covered by a boot having bellows walls so as to enable the wheel detector to be installed outdoors on the rail of a railway track and to withstand severe environmental conditions. A pair of such switches, together with blocks of compressible, resilient material which support contacting surfaces in close proximity to each other and longitudinally spaced along the railway track, is assembled in an integral unit so as to detect not only the presence but also the travel direction of the railway wheels and the axles which connect them.

Railway 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 indication, the operation of the system relies on a sensing means which produces two distinct output signals. The sensing means includes a biasing arrangement for providing, even in the absence of wheel-axles, a steady output signal derived from the path of normal feed current flow. This bias signal is countered or opposed by a wheel sensing signal from the same sensing means responsive to flux level changes resulting from the presence of particular directional components of wheel-axle shunt current, whereby a dip or net reduced signal is effectuated; in the case of open circuit conditions, the output indication goes to zero when there are no wheel-axles in the detection zone.

Vital track circuit wheel detector

The invention is particularly useful for counting the passengers moving into and out of a common carrier vehicle such as a motor bus. Three ultrasonic ranging stations are provided to determine the presence and absence of passengers at three successive positions at the bus entrance. The three positions may correspond respectively to three steps through the entrance. Sequence logic circuitry is included for analyzing the sequence of detection of passengers at the three different ranging stations to establish a count of the number of passengers entering or leaving.

Automatic counting system for passages

Apparatus for detecting the presence and position of individual wheels or wheel-axles of railroad cars. The apparatus involves no moving parts and basically senses the presence of a car wheel by sensing a shunt current flowing through the car wheel-axle set. The apparatus or system includes a transmitter which develops a high frequency AC signal which is impressed across the rails, and a sense or pick-up coil which is sensitive to the fields produced by currents flowing up through the radius of the wheel, whereas it is substantially unaffected by fields produced by the currents flowing in the rails. A pair of current-carrying loops is provided, the first loop including a pair of rails and a pair of boundary shunts connecting said rails; the first loop being subdivided for current flow into two substantially equal portions with respect to a detection zone center line; the second loop extending in close proximity to and inside said first loop, said second loop likewise being subdivided for current flow.

Track circuit principle wheel detector

A track circuit signalling system for an electrified rapid transit system using significantly fewer components is provided. Instead of a transmitter and receiver at each track circuit boundary, alternate boundaries have transmitters only; and the intermediate boundaries have two receivers. The coupling units for the two receivers are more economical than the prior art coupling unit for coupling the transmitter-receiver combination. The transmitters on each side of a receiver pair transmit signals on different carrier frequencies. Each transmitter transmits in both directions from its location. Of the two receivers at a given boundary, one is tuned to respond to signals from the transmitter on one side, while the other receiver of the pair is tuned to respond to signals from the transmitter on the other side. For special applications using overlapping track circuits, selected transmitters may be omitted and a single receiver used on each side of the omitted transmitter.

Track signalling system

Apparatus for detecting the presence of flat wheels on railroad cars, comprising a high frequency transmitter or source connected so that the rail feed points are staggered or offset with respect to the detector apparatus. As a result, the transmitter cannot be completely shorted by a wheel axle; also, the stagger arrangement permits the overlap of two test sections so that no part of the wheel circumference is missed by the detector. Also the use of current detection of the transmitted signal minimizes loading effects on the received signal by adjacent wheel axle sets.

Flat wheel detector

A stretch of railway track, has a high frequency track circuit transmitter and receiver and a cab signal transmitter coupled across track rails at each of several locations marking the ends of track sections along a stretch of railway track. Each location has an impedance bond having a primary winding connected across the track rails and having toroid secondary windings tuned to assigned distinctive high frequencies for coupling a track transmitter and a track receiver to the track rails. A loop circuit is also provided at each location, including a tuned loop, for inductively coupling a cab signal code transmitter to the track rails independent of the impedance bond. The tuned toroid coils and the loop circuit are connected in series to one end of a two wire line circuit, which, at its other end, is connected to a track circuit high frequency transmitteer, a track circuit receiver, and a cab signal transmitter connected in multiple.

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Rochester, NY, United States of America

Klaus H Frielinghaus