US2082179A - Railway traffic controlling apparatus - Google Patents

Railway traffic controlling apparatus Download PDF

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US2082179A
US2082179A US39461A US3946135A US2082179A US 2082179 A US2082179 A US 2082179A US 39461 A US39461 A US 39461A US 3946135 A US3946135 A US 3946135A US 2082179 A US2082179 A US 2082179A
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contact
switch
motor
circuit
hand
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US39461A
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Bernard E O'hagan
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Hitachi Rail STS USA Inc
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Union Switch and Signal Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L5/00Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals
    • B61L5/06Electric devices for operating points or scotch-blocks, e.g. using electromotive driving means
    • B61L5/062Wiring diagrams

Description

June 1, 1937.
B. E. OHAGAN RAILWAY TRAFFIC CONTROLLING APPARATUS F ile d Sept. 6, 1955 Gmtrolled $10060! 5:4 ofi SM.
Colzzl'olled by 64 7 29 78 Selector of SN.
' INVENTOR Bernard EZOZlagazz HIS ATTORN EY Patented June 1, 1937 llNl'i'E STATES PATEN QFFEQE RAILWAY TRAFFIC CONTROLLING APPARATUS Application September 9 Claims.
switch through the medium of a hand lever. In
such dual switch machines, it is desirable to prevent automatic restoration of the switch by the motor to the position corresponding to the position of the remote control lever after the switch has been hand operated and the selector restored to its normal position, since premature or accidental restoration of the selector to its normal position while the switch is being used under hand operation might cause the switch to be moved by the motor with a train passing thereover.
Accordingly, a feature of my invention is the provision of novel and improved apparatus for interlocking between the motor operated means and the hand operated means, and which apparatus, when the switch machine has once been taken over by hand operation, renders the motor ineffective until. after there has been manipulation of the control. lever at the remote office. In actual practice, the procedure for taking over hand operation of a switch is accomplished by the trainman receiving instructions from the remote operator that hand operation of the switch is permitted, the operator taking steps to assure oat manipulation of his control lever is avoided until he later receives a message from the trainman that hand operation has terminated. Hence with apparatus embodying my invention, if a premature restoration of the selector occurs, a false movement of the switch is avoided, but after hand operation is completed the operator is able again to take over control of the switch notwithstanding the fact the trainman may have left the switch in the position opposite that occupied previous. to hand operation.
I will. describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.
In the accompanying drawing, Fig. 1 is a diagrammatic view illustrating one form of apparatus embodying my invention when applied to a well known type of switch operating appara- 6, 1935, Serial No. 39,461
tus utilizing direct current. Fig. 2 is a diagrammatic view illustrating a second form of apparatus embodying my invention when applied to switch operating apparatus wherewith alternating current is utilized.
Similar reference characters refer to similar parts in both views.
Referring to Fig. l, the reference character S designates a railway track switch which is actuated by an electric motor M or by a hand operated lever L through the medium of a suitable switch operating mechanism SM. The mechanism SM may be of any of the standard types, and since its specific structure forms no part of my present invention it is not shown in the drawing for the sake of simplicity. One form of switch operating mechanism that may be used is that disclosed in the United States Letters Patent No. 1,796,323, granted March 1'7, 1931, to C. W. Dalzell and E. G. Little for Railway switch operating apparatus.
The switch S operates a circuit controller E comprising a contact 45 closed in all positions of the switch except in the extreme reverse position, and a contact 46 closed in all positions of the switch except the extreme normal position.
The motor M consists of an armature l and a field winding 8, and is governed by a controller designated as a whole by the reference character D, the controller D being in turn controlled by a o pole-changer CL located at any convenient point such as an operators oiiice and which polechanger may be incorporated in a switch lever of an interlocking machine.
The controller D may take different forms and as here shown is of the type disclosed in the United States Letters Patent No. 1,722,36 l, granted July 30, 1929, to H. S. Young, for Railway traffic controlling apparatus, and this controller will be described in connection with the present description only in so far as seems necessary for a full and complete understanding of my invention.
The controller D consists in its essential elements of a circuit controlling electromagnet P, a neutral magnet N and an overload circuit breaker R. The circuit controlling electromagnet P comprises a magnet 9 made up of two windings 9 and 9 and a polarizing winding it] which latter is preferably provided with a permanently magnetized core ll. Pivotally mounted on the core i l is an armature l2, the arrangement being such that when the electromagnet P is supplied by current of one polarity the armature E2 is operated in a counter-clockwise direction to a normal position, that is, to the position illustrated in the drawing, but that when current of the opposite polarity is supplied to the electromagnet P, the armature is swung in a clockwise direction to a reverse position. In either case energization of winding I0 is effected during operation of the armature I2 to strengthen the permanent magnetic flux. Four circuits controlling contacts I3, I4, I5 and I6 are operatively connected with armature I2. It follows that when the arm-ature I2 swings to its normal position, that is, to the position illustrated in Fig. 1, the four contacts I3, I4, I5 and I6 are actuated to a lefthand position, but that when the armature swings to its reverse position, these contacts are swung to a right-hand position. These four circuit controlling contacts are utilized for governing the motor circuits and other circuits as will shortly appear.
The neutral magnet N controls a pivoted armature I1, the lower end of which projects into the path of movement of a portion of armature I2 to prevent movement of armature I2 when the neutral magnet N is deenergized. The armature II carries two contact fingers I8 and I9 adapted to close contacts 20-2I and 22-23, respectively, when the magnet N is energized. A link 24 is pivotally attached to armature I1 and is provided with a slot 25 which at times engages a pin 26 on a rocker arm 21. When magnet N is deenergized and its armature I1 is released, the link 24 moves the rocker arm 21 against the bias exerted by a spring 28 into a position in which a contact finger 29 carried on arm 2! closes a contact 30-3I. When magnet N is energized and its armature I1 is attracted, the link 24 and the spring 28 urge the rocker arm into a position where the contact 30-3I is open.
The circuit breaker R is of the usual and well known type and when current flowing in the winding 32 thereof exceeds a safe value, a detent 33 lifts the link 24 so that the pin 26 no longer engages the end of slot 25 and the spring 28 actuates the rocker arm to open the contact 30- The free end of link 24 is provided with a rounding surface such that when the link 24 is moved to the right subsequent to operation by the circuit breaker R, it again engages the pin 26.
The apparatus as thus far described is that in general use. In addition to this apparatus, I provide an auxiliary circuit for the circuit breaker R and which circuit includes a contact 34 and a resistor 31. The circuit controlling contact 34 is operatively connected with the selector 0f the switch mechanism SM, the arrangement being such that the contact 34 is moved to a right-hand position, that is, to the position illustrated by full lines in the drawing, when the selector is set for operation of the switch by the motor M, and the contact 34 is moved to the left to the position illustrated by dotted lines in the drawing, when the selector is set for operation of the switch by the hand lever L. The contact 34 when moved to the left-hand position com- 7 pletes connection between two contacts 35 and 36, the contact 36 being connected over resistor 31 and wire 46 to the contact 3| associated with contact finger 29 of the circuit breaker R, and the contact 35 being connected with the common terminal C of a source of current. It is to be understood that the entire apparatus is supplied with direct current from any convenient source of direct current such as a battery not shown, the opposite terminals of the source being indicated throughout the drawing by the reference characters B and C.
In explaining the operation of the apparatus of Fig. 1, I will assume that it is desired to move the switch S to its reverse position, that is, to the position opposite that illustrated in the drawing. The operator reverses the pole-changer CL and as a result current flows from the B terminal of the current source over contact arm 38 of the pole-changer CL, wire 39, contact l3, contact I4, winding of neutral magnet N, and to the C terminal of the current source, and the neutral magnet is energized. Magnet N, on becoming energized and attracting its armature I1, closes con tacts 2lJ-2I and 22-43, releases the armature I2 and opens the contact 30-3I. Current is now supplied to the polarizing winding I0 over a simple circuit which includes contact 23-2I, and is also supplied to the magnet 9 over a circuit which includes the B terminal of the current source, contact arm 39 of pole-changer CL, Wires 39 and 15, winding 9 connection 40, winding 9, wire 4|, contact 2223, wire 42, contact arm 43 of the pole-changer CL and to the C terminal of the current source. As a result of such energization of the magnet 9, the armature I2 is operated to its right-hand position. It is to be noted, a path including a resistor 44 and an asymmetric unit 45 is effective in parallel with the winding 9' to improve the operation of the electromagnet. Reversal of contacts I3 and I4 opens the circuit traced for the neutral magnet N and that magnet is deenergized and its armature I! is released with the result the armature I2 is locked in the right-hand position, contacts Zia-2| and ZZZ-23 are opened and the contact 3B-3I is closed. Reversal of the contacts I5 and I 6 in response to the operation of the armature I2, and closing of the contact 3ll-3I complete a motor circuit which extends from the B terminal of the current source over winding 32 of the circuit breaker R, contact 30-3I, wires 46 and 80, contact I5, armature I of motor M, contact I6, contact 4-5 of controller E, field winding 8, and to the C terminal of the current source, and the motor M is actuated to move the switch S to the reverse pcsition, the circuit being opened at the contact 4-5 when the full reverse position is reached. The circuit breaker R is so adjusted that the current flowing in the winding 32 under usual operating conditions of the motor M is not suflicient to actuate the circuit breaker.
If it is desired to restore the switch S to its normal position, the pole-changer CL is restored to the position illustrated by the full lines in Fig. 1. Operation of the controller D and subsequent operation of the motor M in response to the pole-changer CL being restored to its normal position is similar to that described for reversing the switch and it is thought to be unnecessary to repeat the description. in detail. It is to noted, however, that in either operation of the switch if an excessive current flows to the motor M, the circuit breaker R is actuated, the link 24 is raised to disengage the pin 25 and the rocker arm 2'! is forced to the right by the spring 28 to open contact 303I and rupture the motor circuit. It is clear that deenergization of winding 32 of circuit breaker R subsequent to such operation of the contact 30-3I permits the link .24 to fall behind the pin 26 leaving the contact 30 3| latched in the open position. With the contact 30-3I thus latched in its open position, the op erator can again assume control by operating the iii) pole-changer CL. With the neutral magnet N energized in response to such movement of the pole-changer CL, the link 24 is moved to the right and engages pin 26 with the result that when the magnet N is deenergized in response to operation of the electromagnet P, the contact 363I is reclosed and motor M is operated in accordance with the setting of the contacts I and I6.
For operation of the switch by means of the hand lever L, the selector included in the switch mechanism SM is first operated to its reverse position by the trainman, the trainman desiring to operate the switch by hand first obtaining permission from the operator in the remote ofiice.
As set forth hereinbefore such operation of the selector actuates the contact 34 to the position where it completes the connection between the contacts 35 and 36. The closing of the contact 3536 completes the auxiliary circuit for energizing the circuit breaker R, and which circuit extends from the B terminal of the current source over winding 32 of the circuit breaker R, contact 36-3l, wire 46, resistor 31, contact 3536, and to the opposite terminal C of the current source. The resistor 31 is so proportioned that the current flowing in this auxiliary circuit just traced is sufficient to actuate the circuit breaker R. and lift link 24 out of engagement with the pin whereby the contact 363I is opened and is then latched open since the winding 32 is now deencrgized, and the link 24 falls behind the pin 26. If during operation of the switch by means of the hand lever L the selector included in the mechanism SM should inadvertently or otherwise be restored to its normal position and contact 34 thereby moved back out of engagement with the contacts 35 and 36, the contact 30-3I interposed in the motor circuit still remains latched open, and the motor M would not be operated even though the position of controller E might be such ..0 correspond with the position of the contacts i5 and it. for completing a motor circuit otherwise. It is to be seen, therefore, that the auxiliary circuit including contact 34 and resistor 31 effective to trip the overload circuit breaker R of the control apparatus in response to operation of the selector, and thereby cut off power to the motor. Since the overload circuit breaker can be reclosed only by operation of the polechanger CL at the remote ofiice, it is evident that When the breaker has once been tripped by the auxiliary circuit in response to the selector being set for hand operation, the breaker remains open and retains the motor ineffective even should the selector be restored for motor operation. At the termination of hand operation, the operator at the remote ofllce may assume control of the switch by moving the pole-changer CL and causing an operation of the controller D, the contact 3t 3| being reclosed in response to operation of the controller D in the manner described hereinbeiore.
In Fig. 2, the switch S is operated by a motor M! or by the hand lever L through the medium of the switch operating mechanism SM, the same as in Fig. 1, except for the fact that the motor M! is adapted for operation by alternating current. Operation of the motor MI is governed by a control apparatus including a circuit breaker Bi and a control relay DI, the relay DI being, in turn, controlled over the pole-changer CL located at the remote office. The control relay DI as here shown is of the two element type, the local element 41 of which is continuously energized from any convenient source of alternating current such as a generator not shown, the two terminals of the source being indicated by the reference characters BX and CK. The control element 48 of relay DI is energized by current supplied over the pole-changer CL and the two line wires 49 and 56. It follows that when the pole-changer CL occupies the position illustrated by the full lines in Fig. 2, the two elements of relay DI are energized with currents of one relative polarity and the contact fingers 5|, 52 and 53 of relay DI held in the right-hand position as shown, but that when the pole-changer CL is reversed, the two elements of the relay DI are supplied with currents of the reverse relative polarity and the contact fingers 5|, 52 and 53 are held in the left-hand position, that is, the position opposite that shown in Fig. 2.
The circuit breaker RI comprises a magnet 54, a direct current relay 55, a rectifier 56, and a resistor 5'5. The function of the circuit breaker RI and the manner whereby it is actuated will appear when operation of the apparatus of Fig. 2 is described.
In addition to the above control'apparatus, I provide an auxiliary circuit for the circuit breaker RI and which circuit includes a contact 58 and an impedance I3, the contact 58 being operatively connected with the selector of the switch mechanism SM and the impedance 13 being shown in the form of a resistor. The arrangement is such that contact 58 engages two contacts I6 and TI to complete the connection therethrough when the selector is set for motor operation, and is moved to engage contacts I8 and 19 to complete the connection therethrough when the selector is set for operation by the hand lever L.
In describing the operation of the apparatus of Fig. 2. I will assume it is desired to reverse the switch S. The operator reverses the position of pole-changer CL and hence the contacts 5|, 52 and 53 of relay DI are swung from the righthand position to the left-hand position in response to reversal of the relative polarity of the currents supplied to the two elements 41 and 48 of relay Di. Current now flows from the BX terminal of the current source over contact 58 in engagement with contacts 16 and 11, wire 59, contact 5I6I| of relay DI, armature 6| of motor MI, contact 52-62 of relay DI, contact 4-5 of controller E, field winding 63, wire 64, contact 6566 of magnet 54, wire 61, resistor 51 and to the OK terminal of the current source. The relative polarity of the current energizing the armature 6| and field winding 63 of motor MI is such that the switch S is operated to its reverse position where the contact 4-5 is opened and the operation is stopped. It is clear that the voltage drop across the resistor 51 causes rectified current to flow in the winding of relay 55 to energize that relay. The current supplied to the relay 55 due to the usual operating current flowing in resistor 5'! is not sufficient to effectively energize the relay and cause it to pick up and close its front contact 68. In the event an abnormally large value of current fiows, the relay 55 is effectively energized and its front contact 63 is closed. With contact 68 closed, current is supplied from the BX terminal of the current source over contact 53-69 of relay DI, winding of magnet 54, front contact 58 of relay 55 and thence to the CX terminal of the current source, and the magnet 54 is energized to open the contact 65-65 and close its contacts '|0'II.
The magnet 54 is now retained energized over a stick-circuit extending from the BX terminal of the current source, contact 53-69, winding of magnet 54, its own contact ID-II, wire 61, resistor 51, and to the OK terminal of the current source. Consequently, an overload current is effective to operate the circuit breaker RI and latchopen the contact 5566 interposed in the motor operating circuit. To restore the circuit breaker RI, the operator must manipulate the pole-changer CL and cause an operation of the control relay DI. The interval required for the contact finger 53 of relay DI to move from its left-hand position to its right-hand position, or vice versa, is sufficient to deenergize the magnet 54. Operation of the switch S from its reverse position back to its normal position will follow a movement of the pole-changer CL to its normal position in a manner similar to that described for operating the switch to the reverse position.
When the selector of mechanism SM is actuated to initiate operation of the switch by the hand lever L. the contact 58 is moved into engagement with the contacts 18 and I9, and current flows from the BX terminal of the current source over contact 58, resistor 13, wire 54, contact 6566 of magnet 54, wire 61, resistor 51, and to the opposite terminal CX of the current source. The resistor 13 is so proportioned that the current flowing over this auxiliary circuit is sufllcient to cause effective energization of re-' lay 55 and that relay is picked up. Magnet 54 is now energized over the circuit including front contact 68 of relay 55 and contact 53-59 or 53'!2 of relay DI, and is then held energized over the stick circuit previously traced. It is to be seen. therefore, that the auxiliary circuit includ ng contact 58 and resistor 13 is effective to trip the circuit breaker RI in response to operation of the selector for initiating hand oporation of the switch, and the magnet 54 of circuit breaker RI once energized, is stuck energirzed to latch. open the motor operating circuit until such time as the control relay DI is operated, operation of relay DI being accomplished only by manipulation of the pole-changer CL. Consequently, when the breaker RI has once been tripped due to setting the selector for hand operation. the breaker remains operated even after the selector is restored to its normal posiition. It is to be seen therefore that control apparatuses constructed in the manner described for Figs. 1 and 2 are effective to prevent automatic restoration of the switch by the motor to tmv position indicated by the position of the control lever while the switch is being operated by hand.
Although I have herein shown and described only two forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claimswithout departing from the spirit and scope of my invention.
Having thus described my invention, what I claim is:
1. In railway switch operating apparatus including a switch machine adaptable of operation by both a motor and a hand lever and provided with a selector for rendering either the motor or the hand lever effective, the combination comprising an overload circuit breaker including a normally closed contact interposed in the motor operating circuit, another circuit controlling contact operatively connected with the selector for movement thereby, and an auxiliary circuit including said other contact for energizing the circuit breaker with an overload current when the selector is set for hand operation of the switch machine.
2. In railway switch operating apparatus including a switch machine adaptable of operation by both a motor and a hand lever and provided with a selector for rendering either the motor or the hand lever effective, the combination comprising an overload circuit breaker including a normally closed contact interposed in the motor operating circuit, another circuit controlling contact operatively connected with the selector for movement thereby, an impedance, and an auxiliary circuit including said other contact and said impedance for energizing the circuit breaker with an overload current when the selector is set for hand operation of the switch machine.
3. In railway switch operating apparatus including an electromagnetic circuit controller and a switch machine adaptable of operation by both a motor and a hand lever and provided with a selector for rendering either the motor or the hand lever effective, the combination comprising an overload circuit breaker including a normally closed contact interposed in the motor operating circuit and means for retaining said contact open subsequent to the breaker being tripped, means operated by said controller for reclosing said contact in response to energization of the controller, another contact operatively connected with the selector for movement thereby, and an auxiliary circuit including said other contact for energizing the circuit breaker with an overload current when the selector is set for hand operation of the switch machine whereby operation of the switch machine by the motor when the selector is set for motor operation subsequent to hand operation until the circuit controller is energized is avoided.
4. In railway switch operating apparatus including an electromagnetic circuit controller and a switch machine adaptable of operation by both a motor and a hand lever and provided with a selector for rendering either the motor or the hand lever effective, the combination comprising an overload circuit breaker including a normally closed contact interposed in the motor operating circuit and means for retaining said contact open subsequent to the breaker being tripped, means operated by said controller for reclosing said contact in response to operation of the controller, means including a remote control lever for operating said circuit controller, another contact operatively connected with the selector for movement thereby, a resistor, and an auxiliary circuit including said other contact and said resistor for supplying the circuit breaker with an overload current when the selector is set for hand operation of the switch machine whereby operation of the switch machine by the motor when the selector is set for motor operation subsequent to hand operation until manipulation of the remote control lever is prevented.
5. In combination, a switch machine adaptable for operation by both a motor and a hand lever and provided with a selector for rendering either the motor or the hand. lever effective, an electromagnetic circuit controller, an overload circuit breaker including a normally closed contact interposed in the motor operating circuit and provided with means for retaining said contact open subsequent to tripping of the breaker, means operated by said controller to reclose said contact in response to energization of said controller, means including a control lever for at times energizing the controller, another contact operatively connected with the selector for movement thereby, and an auxiliary circuit including said other contact for energizing the breaker with an overload current when the selector is set for hand operation.
6. In combination, a switch machine adaptable of operation by both a motor and a hand lever, an electromagnetic circuit controller, an overload circuit breaker including a normally closed contact interposed in the motor operating circuit and provided with means for retaining said contact open subsequent to tripping of the breaker, means operated by said controller to reclose said contact in response to operation of said controller, means including a control lever for at times operating said controller, a normally open contact adaptable of movement to a closed position in response to initiating hand operation of the switch machine, and an auxiliary circuit including the last-mentioned contact when closed for supplying an overload current to said breaker whereby operation of the switch machine by the motor subsequent tov initiating hand operation prior to an operation of the controller is prevented.
'7. In combination, a switch machine adaptable of operation by both a motor and a hand lever, an electromagnetic circuit controller, an overload circuit breaker including a winding and a normally closed contact interposed in the motor operating circuit and provided with means for latching said contact open subsequent to tripping of the breaker, means operated by said controller to unlatch said contact in response to energization of said controller, means including a remote control lever for at times energizing the controller, a normally open contact operatively connected with said switch machine for movement to a closed position in response to initiating hand operation, and an auxiliary circuit including the winding of said breaker and said last mentioned contact for supplying an overload current to said breaker whereby operation of the switch machine by the motor subsequent to initiating hand operation until after manipulation of the control lever is prevented.
8. In combination, a switch machine adaptable of operation by both a motor and a hand lever, a control relay having a normal and a reverse position, a remote control lever for governing said relay, a circuit breaker including a control element and a normally deenergized contact controlling magnet and arranged with the control element and a back contact of said magnet interposed in the motor operating circuit, an energizing circuit governed by said control element for energizing the magnet in response to an overload current, a stick circuit for said magnet including either a normal or a reverse contact of the control relay, a normally open contact operatively connected with the switch machine for movement to a closed position in response to initiating hand operation, an impedance, and an auxiliary circuit including said last-mentioned contact and the impedance for supplying an overload current to said control element whereby operation of the switch machine by the motor subsequent to initiating hand operation until after the control lever has been operated is prevented.
9. In railway switch operating apparatus including a switch machine adaptable of operation by both a motor and a hand lever, the combination comprising an overload circuit breaker including a normally closed contact interposed in the motor operating circuit, a normally open contact adaptable of movement to a closed position i in response to initiating hand operation of the switch machine, and a circuit including the lastmentioned contact when closed for supplying an overload current to said circuit breaker whereby the motor is rendered inefiective during hand operation of the switch.
BERNARD E. OI-IAGAN.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2769901A (en) * 1951-06-16 1956-11-06 Westinghouse Air Brake Co Railway switch controlling apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2769901A (en) * 1951-06-16 1956-11-06 Westinghouse Air Brake Co Railway switch controlling apparatus

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