US1969084A - Traffic controlling system for railroads - Google Patents

Description

Aug. 7, 1934.

R. C. LEAKE TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Filed April 30, 1931 FIG. 1.

INVENTOR Richard C. Lea ke,

Patented Aug. 7, 1934 PATENT- OFFIQE TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Richard C. Leake, Rochester, Y., assignor to General Railway Signal Company, Rochester,

Application April 30, 1931, Serial No. 533,934

14 Claims.

This invention relates to traffic controlling systems for railroads, and more particularly pertains to relay systems for use therewith.

In traflic control systems of the directcontrol type, as disclosed, for example, in the application or" S. N. Wight, Ser. No. 120,423, filed July 3, 1926, a remotely controlled polar-neutral relay is usually employed to govern the operation of the switch and signals at a particular track location. Similarly, in a traific control system or the selector type, as disclosed, for example, in the application of N. D. Preston et al., Ser. No. 455,304, filed May 24, 1930, a three-position polar relay is employed in the stepping circuit at each field location for the reception of control impulses at that location.

In accordance with the present invention, it is proposed to provide two neutral relays so connected in combination as to be responsive to changes in polarity, which combination may be employed similarly as the polarized relays above referred to, and other similar practical applications of polarized relays. This is accomplished by providing local energy for normally energizing the two neutral relays, with the connections so made that the application of energy by the remote control circuit will reduce the current substantially to zero in one or the other of the neutral relays dependent upon the polarity of the applied potential.

Other objects, purposesand characteristic features of the present invention will be in part obvious from the accompanying drawings and in part pointed out as the description of the invention progresses. V

In describing the invention in detail, reference will be made to. the accompanying drawing, in which like referencecharacters having distinctive exponents will be employed to designate corresponding parts throughout the several views, and in which:- v v Fig. 1 illustrates a remote control system for railroad track switches as one embodiment of the present invention;

Fig. 1A illustrates, a modified arrangement of the relays employed in the system of the present invention; and

Fig. 13 illustrates a second modified arrangement of the relays employed in the system of the present invention. 7

With reference to Fig. 1 of the accompanying drawing, a railroad track switch TS is indicated as being operated to'normal 'or reverse extreme positions by a switch machine SM which may be of any suitable type, such for example, as the switch machine disclosed in the patent to W. K. Howe, Patent No. 1,466,903, dated September 4, 1923.

This switch machine SM is governed from a control oflice through the medium of a control lever L, a polarized control circuit and a relay system included within the dotted rectangle designated R. The relay system R includes two neutral relays 5 and 6, two local battery sources 7 and 8, and the respective contacts of the two neutral relays. These neutral relays 5' and 6 are contemplated as being of the tractive type having such operating mechanisms as to suitably operate their respective contacts to either energized or deenergized conditions in accordance with the energized or deenergized conditions of the respective relay windings. However, it is to be understood that any other suitable type of relay may be employed, such as, for example, a motor type relay having rotor and field windings, as distinctive from the tractive type.

Normally the windings of the respective neutral relays 5 and 6 are energized by the battery sources 7 and 8 in series through a circuit from the positive terminal of battery '7, through wires 9 and 10, windings of relay 6, wire 11, to the negative terminal of battery 8, from the positive terminal of battery 8, through wires 12 and 13, windings of relay 5, wire 14, to the negative terminal of battery '7. The direction of the flow of current due to this circuit is indicated by the arrows within the respective relays. Thus, the contacts of the two neutral relays 5 and 6 are normally in energized positions opening the control circuits of the switch machine SM.

At the control office, a battery 15 is provided having a center or intermediate tap connected to a line wire 16 extending to the field location while the positive and negative terminals of this battery are arranged so that positive or negative potential is applied to line wire 17, through suitable circuit controlling means illustrated in this embodiment of the present invention as a three- -position manually operable control lever L.

tors or the like to provide a potential at the field location equal to the potential provided by the respective batteries 7 and 8.

With the lever L in a non-contacting position as shown, the line wires 16 and 17 are deenergized and the neutral relays 5 and 6 are energized, so that the potential drop across points 20 and 21 is substantially zero, considering of course that the batteries 7 and 8 have equal internal resistances and provide equal terminal potentials, and considering that the relays 5 and 6 have equal resistances.

Thus, when the lever L is moved to one position or the other so as to apply potential across points 20 and 21 equal to the potential provided. by each of the batteries 7 and 8, current flows through one of the two branches of the parallel circuit in accordance with the sum of the applied potential and the potential of the battery within that branch dividedby the resistance of the respective branch while there is no current flow in the opposite branch. In other words, with a particular polarity appliedthe currents in one branch have the same direction and are additive, while in the other branch, the algebraic sum of the currents is substantially zero, thus deenergizing the relay in that branch More specifically, let Us assume that the lever L is moved to the right which applies positive potential to the point 20 and negative potential to the point 21, thereby causing a current to flow from the positive terminal of battery 15, lever L in a right hand position, wire 17 to point 20, wire 10, windings of relay 6, wire 11, battery 8, wire 12 to point 21, wire 16, to the mid-point of battery 15. The direction of the current in this branch is indicated by the arrow beneath relay 6. Also, a circuit is closed from point 20, through wire 9, to the positive terminal of battery 7, from the negative terminal of battery 7, through wire 14, winding of relay 5, wire 13, to point 21. The poten-- tial applied to points 20 and 21 by battery 15 would cause a current to fiow from that battery through this branch including relay 5 in the direction indicated by the arrow above relay 5, if it were not for battery 7, but the potential of battery 7 opposes the applied potential. Thus, the

currents in the branch including relay 6, and

battery 8 are additive so that the current is substantially double the normal current provided in that branch by the batteries 7 and 8; while the algebraic sum of the currents in the branch including relay 5 and battery '7 is substantially zero. With. substantially zero current in the relay 5, its magnetic flux is reduced to substantially zero so that its armature falls away or drops. 7 With the neutral relay 5 deenergized, its contacts are caused to assume deenergized positions, in which the reverse operating circuit of the switch machine is closed fromthe positive terminal of battery 25, through wires 26 and 27 front contact 28 of neutral relay 6, back contact 29' of neutral relay 5, reverse operating wire 30, through the operating mechanism of the switch machine SM to the common return wire 31, thence to the nega ive terminal of battery 25. The switch machine operates the track switch to the reverse position in the usual manner and after completing such operation opens its reverse operating circuit, all as described in the above mentioned Patent If the lever L is moved tot-he left hand position, it is obvious that the polarity applied to the points 20 and 21 is reversed, hence causing the neutral relay 6 to be deenergized while the neutral relay 5 remains energized, thus closing the normal operating circuit of the switch machine including the normal operating wire 32 and returning the track switch TS to its normal position. Such operation will not be described in detail asit will be understood by analogy to the above description.

With reference to Fig. 1A of the accompanying drawing, a modified form of the relay system B is illustrated, wherein the local energizing circuits of the relays 5 and 6 are separate from the remotely controlled circuits by providing two separate windings on each of these relays.

The lower windings of these relays 5 and 6 are energized from the positive terminal of battery 50, through wire 51, windings of relay 6 wire 52, windings of relay 5*, wire 53, to the negative terminal of battery 50. This energizing circuit causescurrent to flow in these lower windings as indicated by the arrows 54 and 55. The application of suitable potential to the points 20 and 21 causes current to flow through the upper windings of these relays so that the magnetic fluxes produced by the upper and lower windings of one relay are additive, while in the other relay the resultant flux is substantially zero. In other words, the lower or local windings of these relays may be said to be connected differentially with respect to each other as compared with their negative potential to point 21*, it is obvious that currents will flow in the upper windings of the relays as indicated by arrows 56 and 57. Hence, the armature of the relay 5 will drop away, while the armature of the relay 6 will remain in an energized position.

If on the other hand the polarity applied to the points 20 and 21% is reversed, the direction of current flow in the upper windings is indicated by arrows 58 and 59 thus causing the armature of relay 6 to drop away while the armature of relay 5 will remain energized.

It is to be understood that the potential applied to the upper windings in series must provide such a current value, in accordance with the ratio of turns between the upper and lower windings of each relay, that the magnetic flux component resulting from such current in each relay will substantially equal in value the flux component resulting from the current in the respective lower windings.

With reference to Fig. 1B of the accompanying drawing, a modified form of the relay system B is illustrated, wherein the relays 5 and 6 are .provided with local and remotely controlledwindings as explained for Fig. 1A, the only difference being that the local or lower windings of these relays are connected in multiple with the local battery source 50*, although the local or lower windings of the relays are differentially connected with respect to each other as compared to the upper windings. However, the resulting operation of the relays is the same and may be understood by analogy to the description for Fig. 1A.

Although the present invention has been shown as embodied in the remote control of a railroad track switch, it is to be understood that the principles involved may be applied to various other applications where polar relays are employed. Also, the specific voltages of the various batteries, their internal resistance, the resistance of the various windings of the relays involved, as well as the resistances of the line circuits must all be ascertained and determined. for the particular application in practice in accordance with the usual engineering practices. Also, although only two circuits have been shown selected through the relays 5 and 6, it is to be understood that four distinctive selections can be made, three in normal operation and the fourth under the abnormal condition of failure of the local source or sources. The third selection (not shown) can be made through a front contact of relay 5 in series with a front contact of relay 6. The fourth selection (not shown) can be made through a back contact of relay 5 in series with a back contact of relay 6.

Having described a trafiic controlling system as embodying the present invention, it is desired. to be understood that this form is selected to facilitate in the disclosure of the invention rather than to limit the number of forms which it may assume; and, it is to be further understood that various modifications, adaptations and alterations may be applied to the specific form shown to meet the requirements of practice, without in any manner departing from the spirit or scope of the present invention except as limited by the appended claims.

Having described my invention, I now claim:-

1. A relay system. comprising, two neutral relays connected in a normally energized series circuit with local sources, and means for applying potential at two points in said series circuit having the same potential, whereby one or the other or" said two neutral relays is deenergized depending upon the polarity of said applied potential.

2. In a relay system, in combination, two neutral relays, a local source or" electrical energy, and means connecting said neutral relays to said 10- cal source to be controlled thereby, a remote control circuit for the relays, said remote control circuit being connected to the relays so as to make them responsive to the polarity of potential applied to said remote control circuit.

3. In a relay system, two neutral relays each having local and line windings, means energizing said local windings diiIerentially with respect to each other, means energizing the line windings in series, whereby one or the other of said two relays is deenergized depending upon the polarity applied to said line windings.

l. In a relay system, two neutral relays each having an armature and two separate windings for actuation thereof, means energizing one winding of each relay from a local source to cause actuation of said armaturee, and means for energizing the others of said windings from a remote source to neutralize the actuation of said armatures by said first mentioned energized windings.

5. In a relay system, in combination, two neutral relays, means normally energizing said neutral relays in a series circuit, and means applying potential to said series circuit so as to neutralize said means normally energizing said neutral relays with respect to one or the other of said relays depending upon the polarity of said applied potential.

6. In a relay system, two neutral relays, means continuously energizing said neutral relays differentially with respect to each other, and means remotely controlled for energizing said neutral relays in series, thereby deenergizing one or the other of said neutral relays depending upon the polarity of said series energization.

7. In a relay system, two neutral relays each having an armature and two separate windings, means for energizing one of the windings of each relay from a local source to actuate the armatures, and means for energizing the others of said windings from a remote source of energy to neutralize the actuation of the armatures by the first mentioned energized windings.

8. In a relay group, a plurality of neutral relays, a single source of energy arranged to position the relays in attracted positions, and a circuit for controlling the relays, means for at will placing energy of different polarities on the control circuit for at will selectively de-energizing the relays in accordance with the polarity of energy applied to the control circuit.

9. In combination, two neutral relays, and two local sources of energy connected in a series circuit with sources and relays alternating, and means for applying potential of selected polarity to two spaced points in said series circuit.

10. In combination, two neutral relays, and two local sources of energy connected in a series circuit with sources and relays alternating and the sources arranged cumulatively, and means for applying potential of selected polarity to two spaced points with a source and a relay between the points in said series circuit.

11. In combination, two neutral relays each having two windings, a local source of energy connected in a series circuit with one winding of each relay, and a series circuit including a remote source of energy connecting up the other windings of the relays.

12. Two neutral relays, a holding winding on each relay, a local source of energy connected to the holding windings in multiple, and a control winding on each relay connected in a series circuit so that a given polarity of energy placed on the control winding causes one control winding only to oppose its holding winding.

13. Two neutral relays, a holding winding on each relay, a local source of energy connected to the holding windings in multiple to energize the holding windings in opposite directions, and a control winding on each relay connected in a series circuit and means for placing potential of selected polarity on the series circuit.

14. Two neutral relays, a holding winding on each'relay, a local source of energy connected to the holding windings to energize the holding windings in opposite directions, and a control winding on each relay connected in a series circuit and means for placing potential of selected polarity on the series circuit.

RICHARD C. LEAKE.

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