US2081900A - Automatic switching system for railroads - Google Patents

Automatic switching system for railroads Download PDF

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US2081900A
US2081900A US540984A US54098431A US2081900A US 2081900 A US2081900 A US 2081900A US 540984 A US540984 A US 540984A US 54098431 A US54098431 A US 54098431A US 2081900 A US2081900 A US 2081900A
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switch
track
strip
miniature
control
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US540984A
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Ned C L Brown
George M Seidel
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SPX Corp
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General Railway Signal Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L17/00Switching systems for classification yards

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Punching Or Piercing (AREA)

Description

June 1, 1937. N L, BROWN E L 2,081,900
AUTOMATIC SWITCHING SYSTEM FOR RAILROADS Original Filed May 29, 1931 4 Sheets-Sheet 1 INSULA TION INSULATION INVENTORS Cg Brown ""4 GMSeidel June 1, 1937. N. c. BROWN ET AL AUTOMATIC SWITCHING SYSTEM FOR RAILROADS 4 Sheets-Sheet 2 Original Filed May 29, 1931 v N M M 04 m a 0 N T E n T 0 June 1, 1937. N. c. L. BROWN ET AL 2,081,900
AUTOMATIC SWITCHING SYSTEM FOR RAILROADS 4 Sheets-Sheet '3 Original Filed May 29, 1931 THEIR ATTORNEY Patented June 1, 1937 UNITED STATES PATNT OFFIQE.
AUTOMATIC SWITCHING SYSTEM FOR RAILROADS Ned G. L. Brown,
Seidel, Rochester, N.
Application May 29,
Renewed September 23,
13 Claims.
This invention relates in general to an automatic switching system for railroads and more particularly to a system for recording predetermined sequential positions of switches and for automatically operating the switches in accordance therewith.
In large railway freight terminals, it is customary to break up incoming trains by switching individual or groups of cars into various tracks classified according to their destination. These classified cars are then transferred to outgoing trains over routes which include their destination points. In classifying these incoming cars, information is received concerning the order of the cars in the train and the Weight and destination of each car preceding the actual arrival of the incoming train. From this information, a switch list is prepared to enable the yard conductor and yard switch operators, located at Various towers in the yard, to properly classify the cars. This list shows the initial and number of each car and the order in which they will arrive as well as the gross weight and the classification track to which they are assigned. Such yards are usually equip ped with power-operated switches and poweroperated car retarders controlled from the towers so that, with the switch list, it remains for the operators to set up the proper routes and to control the motion of the cars over these routes.
It is proposed in accordance with this invention to provide a means which is applicable to a switching system, such as the above, whereby a record of a predetermined succession of switching routes may be made and later automatically set up in accordance with this record.
Other objects, purposes and characteristic features of the invention will appear as the description thereof progresses, during which references will be made to the accompanying drawings which show the invention in a manner to make it easily understood, rather than with the view of showing the particular construction preferably employed in practice, and in which:-
Fig. l is a diagrammatic illustration of a recording apparatus and circuit according to this invention.
Fig. 2 is a diagrammatic illustration of an automatic operating apparatus and circuit also according to this invention.
Fig. 3 is an illustration of a system employing the apparatus illustrated in Figs. 1 and 2.
Fig. 4 is a table of the records for a typical series of switching routes in the system in Fig. 3.
Referring now to Fig. 1, an apparatus for recording various routes over a single switch of a Scottsville, and George M. Y., assignors to General Rochester, N. Y.
miniature track diagram is illustrated in the dotted rectangle R. The record of such routes is to be made on a strip S of flexible insulating material, such as paper, which may have spaced perforations I along each edge which are engageable by projections 2 on sprocket wheels 3 rigidly mounted on a shaft 4.
The strip S is threaded between a lower plate 5 and an upper plate 0 which have laterally spaced holes therein arranged to receive punching plungers l and 8 which are normally biased to a position in the upper plate 5 only. Individual operating means for the punching plungers I and 3 are diagrammatically shown as electro-magnetic coils 9 and I0 which operate armatures ll and I2 respectively connected to the punching plungers l and 8. Insulated electrical contacts l3 and M are included on the operating mechanism which are adapted to engage fixed resilient contacts I5 and Hi respectively when the punches are in their operated position. The punching plungers l and 8 are normally biased to an upper position out of engagement with the strip S by their respective springs I1 and I8.
Suitable means for intermittently moving the strip S between the plates 5 and 6 is also included and controlled from the contacts l3 and M. This means is shown as an electro-magnet l9 operating an armature which is biased to a retracted position by a spring 2 l The end of the armature 20 carries a pawl 22 which is biased into engagement with the projections 2 on the sprocket wheel 3 by a spring 23. A ratchet dog 24 is rigidly pivoted so as to engage the projections of the sprocket wheel 3 and, as obvious, permit only unidirectional rotation thereof as indicated by the arrow.
This recording apparatus just described is electrically connected to a switch on a miniature model or diagram of the railway track system. The arrangement of this miniature track diagram is diagrammatically illustrated in Fig. l as a section of insulating material 25 typifying the track and divided each side of an intersection as shown. The division in the straight section has a resilient metallic strip 25 which is engageable when depressed with a lower metallic member 21 so as to make an electrical connection therebetween and complete an energizing circuit for coil 9. Similar contact strips 28 and 29 are included in the division of the diverging section of miniature track 25 and is arranged to complete a like energizing circuit for the coil iii.
In operating the recording apparatus, a strip S of indefinite or suitable length is threaded into a position for punching and a stylus or an instru ment for depressing the contact strips 26 and 28 is manually moved over the desired route in the miniature track diagram. If the route to be re corded includes the straight section in Fig. 1, the stylus depresses the contact 26 only which closes the following circuit:from one terminal of a source of energy, wire 39, contact strip 25 depressed, contact 27, wire 3 I, the windings of the coil 9, and wire 32 to the opposite terminal of the source. This energizes the coil 9 which forces the punching plunger down through the strip S by attracting the armature H thus punching a hole therein.
The armature l l in this attracted position, completes a circuit from one terminal of a source of energy, wire 33, contacts [5 and i3, wires 34 and 35, winding of the ratcheting electro-magnet I9, and wire 36 back to the source. This energizes the electro-magnet I9, thus attracting its armature 20 which allows its pawl 22 to slip over one projection on the sprocket wheel 3. When the stylus passes over and releases the contact 2-13, the punching coil 9 is deenergized, which allows the armature H to return to its biased position, thus deenergizing the ratcheting electro-magnet I9 and allowing the spring 2! to rotate the sprocket wheel 3 one division in a clockwise direction by means of the pawl 22 in which position it is retained by the dog 24.
It is now obvious that if the next route over this switch, which is to be recorded, includes the diverging section of the miniature track diagram shown, the punching coil IE] will be energized by depressing the contact 28 thus causing a hole to be punched at a position nearer the other edge of the strip S. It is also obvious that the ratcheting electro-magnet I9 is again energized by the engaging of the contacts i l and IE, to thus move the strip forward one division as described in the previous operation. Any number of routes over this switch may thus be recorded by the punching of holes in the strip S either on the right or left side according to the route over the switch and these holes will obviously be spaced along the length of the strip by the ratcheting thereof between punchings.
A record of movements over a switch made in the apparatus just described may then be taken from the recording apparatus and threaded into a suitable apparatus for automatically operating the associated track switch, as is diagrammatically shown in Fig. 2. The strip S can be discontinuous or be continuous and extend from the recording apparatus to the operating apparatus and the record stored in the form of a loop between the two apparatus. In either case, the record strip must be positioned in the operating apparatus for the first operation thereof.
Referring now to Fig. 2, the automatic operating apparatus is included in the dotted rectangle O, and includes a ratcheting means for the strip S which ratcheting means is shown as being of the same type as employed in the recording apparatus. The strip S is thus intermittently stepped between a contact plate 3! and two brush members 38 and 39 which may be resilient spring contacts mounted on a fixed insulating member 39, as shown. These brushes 38 and 35) are laterally spaced the same distance as are the punching plungers 7 and 8 of the recording apparatus and consequently when the record strip S is placed therein, either brush 38 or 39 makes an electrical contact on the plate 31 according to whichever side contains the punched hole recording that particular route.
The other part of the automatic switching apparatus includes a compound track relay T having a winding 4! controlled by a track section including a track switch TS, and a stick winding 42. A switch machine SM is connected to operate the track switch TS and is operated through suitable control relays N and R. A conventional manual control lever C for the switch machine SM is shown and a selecting switch A is included which can shift the control of the switch machine SM to either the automatic means or the manual control lever C. A manually operable switch 43 is also provided, by which the record strip S can be manually ratcheted forward, if desired, and which will be more fully described hereinafter.
The operation of the system shown in Fig. 2 requires placing the record strip S so that the first hole therein allows one of the brushes 38 or if? to make contact with the contact plate 3?. Assuming that this first route record is of a normal switch position as shown, the following circuit is completed:beginning at one pole of a source of energy, wire M, contact plate 3?, brush 38, wire contact finger 4S and front point of relay T, wire t'l, contacts 48 and 49 of switch A in the automatic operating position, wire 56, control relay N, and wire 5| to the opposite pole of the source of energy. This energizes the relay N which operates its armature 51 to complete the following switch operating oircuit:-beginning at one pole of a source of energy, wire 52, contact finger 53 and front point of relay T, wire 54, winding A2 of relay T, wires 55 and 56, contact finger 5i and front point of control relay N, wire 58, switch machine contacts 59 bridged by-contact 6V] in its dotted position, winding 51, armature A, brake winding 62, wire 63 to the opposite pole of the source of energy.
The completion of the circuit just described operates the track switch to its normal position as shown and this operating current maintains the relay T in its energized position even in the event that the winding 4| be deenergized by the entrance of a car into its governing track section. This operation of the switch machine SM moves the contact 60 from its dotted position to its solid position which prepares the reverse operating circuit for operation, but it is obvious that if the next route record is of a normal switch position no operation of the switch machine SM will take place as the operating circuit is incomplete because the recorded switch position already exists.
When the switch TS has been positioned for the first route as just described, the proper car or group of cars are released, and enter the track section over the switch TS thereby deenergizing the relay T and closing the following circuit to the ratcheting magnet G iz-beginning at one pole of a source of energy, wire 65, contact finger 66 and back point of relay T deenergized, wire 67, switch 13 normal, wire 88, winding of ratcheting magnet 6 wire 69 to the opposite pole of the source of energy.
The completion of this circuit energizes the ratcheting magnet 64 which attracts its armature 10 to a position which can move the record strip S forward one division through the sprocket wheels H when the armature I0 is released by the aforesaid car clearing the track section which controls the relay T. It will now be obvious that each cut of cars passing over the switch track diagram thereby TS ratchets the record strip S forward one division which completes a new circuit through either brush 38 or 39, in preparation for the succeeding cut of cars which is to pass over the switch TS and is effective to thus operate the switch TS unless it is already in proper position.
The reverse operating circuit which energizes relay R through brush 39 is so similar to the normal operating circuit previously described that it is considered to be obvious without tracing it in detail. The control wires to and 12 of the relays N and R are respectively connected to the center contacts 49 and 13 respectively of the selecting switch A. Consequently, the reversing of the switch A shifts the control wires 50 and 12 to the contacts 14 and 15 connected to the lever C thereby placing the control of the switch machine SM under the manual lever C and disconnecting the automatic control.
' In the above system, a cut of cars may enter the track section before a preceding cut of cars has cleared the section and thereby prevent the functioning of the ratcheting means and thus throw the record strip out of synchronism with the cuts of cars corresponding to the recorded routes. To again restore a normal condition in this case, the switch 43 is provided which may be operated manually or otherwise to a central position to deenergize the ratcheting magnet 64 when the track section is occupied. Energy is supplied also to a back contact 16 of the switch 43 so that the ratcheting magnet 64 may be successively energized and deenergized by an extreme manual operation of the switch fit, thus ratcheting the record strip S one division forward in case the cars have cleared the track section.
A typical system employing several units of recording apparatus and operating apparatus is diagrammatically illustrated in Fig. 3. It will be noticed that each switch in the actual track system, shown at the top of the drawing, is represented on a miniature track diagram, at the bottom thereof, which may be constructed of insulating material having grooves which represent the track. The two small rectangles 2th Z5 etc., in the grooves at each switch of the miniature track diagram, represent the recording switches which are depressed by the stylus in recording the routes and correspond to switches 26 and 23 in Fig. 1.
It will also be noticed that a dotted rectangle, R indicating a group of apparatus such as inclosed in the dotted rectangle R in Fig. l is connected, in the manner shown in Fig. l, to each switch of the miniature track diagram. An associated dotted rectangle O is included which represents the automatic operating apparatus shown in Fig. 2, and is connected in the manner shown in Fig. 2 to each switch in the actual system. It is proposed in recording various routes for car cuts in such a system to use a stylus, as previously described, which is to be manually traced through the grooves in the miniature depressing definite circuit closing means which record the routes over each switch in the order in which it is to be traversed.
The sections of record strips shown in Fig. 4 illustrate a series of assumed switching routes for classifying a number of cars in the system of Fig. 3. The number of the classification track of Fig. 3, to which the cars are to be switched, is given in order in the vertical column so labeled and dotted lines connect these numbers with the record on the strips of the routes over switches which are traversed. For example, the first cut" of cars is to go to track I, and it is obvious from Fig. 3 that such a move merely requires that switch I be reversed so the first perforation in the record strip for switch i is in the reverse" position thereon. The next to track 2, requires switch I normal and switch 2 normal and this is accomplished by the second perforation in switch record and by the first perforation in Switch 2 record. From this a comprehensive idea of the operation of the system may be obtained by keeping in mind that each switch record strip is manually or otherwise positioned for the first route over its associated switch, and after the first traversal thereof, the record strip is automatically stepped ahead after each traversal and the switch positioned for the next route which includes that switch.
Having described an automatic switching system as a specific embodiment of 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 thus described our invention, what we claim is:
i. In an automatic switching system for railway yards, in combination, a miniature track diagram corresponding to the car yard having selective circuit controlling means associated with each miniature switch thereof, a perforable insulating strip associated with each miniature switch, means controlled by said selective circuit controlling means for distinctively perforating said strips in accordance with various manually selected routes over said miniature switches, control means for each track switch operable to select sequential positions of track switches from its associated perforated strip, each of said in sulating strips being automatically positioned, by a preceding traversal of its track switch by a car, to selectively operate said control means.
2. An automatic switching system for railroads including a track switch, a miniature representation of said track switch, a perforable insulating strip, means associated with said miniature switch for distinctively perforating strip according to a manually traced route over said miniature switch simulating a route over the track switch, and control means receiving said perforated strip and arranged to complete definite control circuits for said track switch in accordance with the perforations in said strip, said control means being arranged to actuate said strip to successive control positions by traversal of said track switch by a vehicle.
In an automatic switching system for railway yards, a plurality of route recording devices each comprising a perforable strip of indefinite length, means for distinctively perforating each of said strips transversely according to manually selected routes of spaced apart vehicles over an associated traific controlling switch, and means including a miniature representation of the associated switch for perforating each of said strips longitudinally according to the sequence of such routes over the associated switch, and means for alining routes according to said perforated strips comprising a plurality of switch operating means controlled in accordance with the transverse position of said perforations of the associated strip and means for actuating each of said strips longitudinally in accordance with the traversal of said sequential routes over each of said switches by a vehicle.
4. In an automatic switching system, an actual track switch and a miniature representation thereof, two spaced electrically operated punches, control means for operating said punches to distinctively perforate a strip of insulating material in accordance with a manual opera tion of an instrument over the miniature representation of the track switch which simulates either a straight or diverging train movement over the actual track switch, means arranged to actuate said strip after each perforation thereof, operating means for the actual track switch controlled in accordance with the perforation in said strip and means arranged to actuate said perforated strip after each traversal of said actual track switch by a vehicle.
5. In an automatic switching system for railway yards, a perforable tape of indefinite length, equi-spaced notches in said tape engageable by sprocket wheels, electro-rnagnetic operating means for said sprocket wheels, spaced electrically operated punches, means including a representation of a track switch for causing the punches to distinctively perforate said tape in accordance with a manually traced route over said representation simulating a train movement over an actual track switch, contacts on said punches arranged to control said sprocket wheel actuating means, and switch operating means arranged to automatically operate a trafiic controlling switch in accordance with previously selected distinctive perforations in said tape.
6. In an automatic switching system for railway yards, a route recording device comprising a plurality of electrically operated perforating means, each perforating means adapted to distinctively perforate an associated paper tape in accordance with a series of predetermined routes over an associated traffic controlling switch, and means for operating each of said switches in accordance with the associated perforated tape comprising sprocket wheels engaging equi-spaced notches in said tape, electromagnetic operating means for said sprocket wheels, insulated contact brushes arranged to selectively energize control circuits for said switch operating means by making electrical contact through said perforations in the paper tape and a control circuit for said sprocket wheel operating electro-magnet governed by the traversal of the associated trafiic controlling switch.
7. In an automatic control system for poweroperated railway switches, a perforable insulating strip threaded between an upper and a lower plate, two transversely spaced electrically oper ated punches in said upper plate each adapted to perforate said strip, electrically operated means arranged to definitely actuate said strip longitudinally, a miniature representation, of the power-operated switch, individual manually operable energizing means for said electrically operated punches, said energizing means being located on said miniature switch to be operated by the manual tracing of the various routes thereover and parallel energizing circuits for said electric strip actuating means operated by said punches.
8. In an automatic control system for poweroperated railway switches, a normal and a reverse switch control relay, a track relay controlled in accordance With the occupancy of a track section adjacent said switch, individual energizing contacts for said normal and said reverse control relays, an insulating strip arranged to deenergize said relay energizing contacts, perforations in said strip prearranged by position and sequence to allow the energization of either of said relay energizing contacts, and intermittent actuating means for said strip controlled by said track relay.
9. In an automatic control system for poweroperated railway switches, a normal and a reverse switch control relay, a track relay controlled in accordance with the occupancy of a track section adjacent said switch, individual energizing contacts for said normal and said reverse control relays, an insulating strip arranged to deenergize said relay energizing contacts, perforations in said strip prearranged by position and sequence to allow the energization of either of said relay energizing contacts, intermittent actuating means for said strip controlled by said track relay, a manually operable control switch arranged to energize either of said switch control relays and a manually operable selecting switch arranged to selectively place the control of said switch control relays with either said automatic energizing contacts or with said manually 0perable control switch.
10. In an automatic control system for poweroperated railway switches, a switch machine operably connected to said railway switch, a normal and a reverse control relay for said switch machine, a relay having an operating winding energized by a track circuit including said railway switch, an operating circuit for said switch machine including a front point and a holding winding on said track relay and a contact of either said normal or said reverse control relays and energizing means for said normal and said reverse control relays; including contact means closed in accordance with prearranged distinctive perforations on a record strip.
11. In an automatic control system for poweroperated railway switches, a normal and a reverse switch control circuit, a track relay controlled in accordance with the occupancy of a track section adjacent said switch, individual energizing contacts arranged to selectively complete either said normal or said reverse control circuit in accordance with prearranged perforations in a record strip, electro-magnetic actuating means for said record strip controlled by said track relay and a manual control means in. series with said track relay control whereby said electro-magnetic actuating means may be either deenergized or energized.
12. In an automatic switching system for railway yards, in combination, a track switch, a miniature track diagram having selective circuit controlling means associated with a miniature switch thereon corresponding to the track switch, a perforable insulating strip associated with the miniature switch, means controlled by the operation of an instrument over the selective circuit controlling means for distinctively perforating the strip in accordance with the various selected routes over said miniature switch, and control means for the track switch operable to select sequential positions of the switch from its associated perforated strip.
13. In an automatic switching system for railway yards, in combination, a track switch, a miniature track diagram having selective circuit controlling means associated with a miniature switch thereon corresponding to the track switch, a perforable insulating strip associated with the miniature switch, means controlled by the selec- 10 tive circuit controlling means for distinctively perforating the strip in accordance with manual operations simulating various train movements over said switch, control means for the track switch operable to select sequential positions of the switch from its associated perforated strip, the control means being automatically positioned, by a preceding traversal of its switch by a vehicle, to select such switch positions.
NED C. L. BROWN.
GEORGE M. SEIDEL.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2835206A (en) * 1955-10-27 1958-05-20 Armour & Co Article sorting device
US2898452A (en) * 1954-12-13 1959-08-04 Roland J Berti Switching systems and apparatus therefor
US2941068A (en) * 1954-09-10 1960-06-14 Westinghouse Air Brake Co Automatic switching system for railway classification yard utilizing a punched tape
US3071262A (en) * 1957-12-26 1963-01-01 Bosch And Robert W La Tour Automatic production-conveying and warehousing systems

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2941068A (en) * 1954-09-10 1960-06-14 Westinghouse Air Brake Co Automatic switching system for railway classification yard utilizing a punched tape
US2898452A (en) * 1954-12-13 1959-08-04 Roland J Berti Switching systems and apparatus therefor
US2835206A (en) * 1955-10-27 1958-05-20 Armour & Co Article sorting device
US3071262A (en) * 1957-12-26 1963-01-01 Bosch And Robert W La Tour Automatic production-conveying and warehousing systems

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