US1983506A - Time element circuit for traffic controlling systems - Google Patents

Time element circuit for traffic controlling systems Download PDF

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US1983506A
US1983506A US551931A US55193131A US1983506A US 1983506 A US1983506 A US 1983506A US 551931 A US551931 A US 551931A US 55193131 A US55193131 A US 55193131A US 1983506 A US1983506 A US 1983506A
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relay
circuit
contact
thermal
time
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Joseph E Willing
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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
    • B61L21/00Station blocking between signal boxes in one yard
    • B61L21/06Vehicle-on-line indication; Monitoring locking and release of the route

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  • This invention relates to time element circuits Willing, Serial No. 463,903 filed June 26, 1930 and more particularly to a means for definitely which are oppositely mounted at one end on a conditioning a railway signalling circuit after suitable support, such as the member 3.
  • elements 1 and 2 each carry electrical heating
  • a track units 4 and 5 respectively, which elements tend 60 switch and a signal governing movements over to deform in a direction indicated by the respecthis switch are controlled by an operator which tive small arrows thereon when heated above a obviously necessitates employing means to prenormal temperaure.
  • a defl- A relay M which may be either nite time elapse between the operating of the manually or automatically controlled in ac signal to stop and the moving of its associate cordance with traffic conditions as is clearly detr k w h, Whi h m is adequate for an onscribed in application above referred to.
  • a 75 coming train to either stop clear of the switch stick relay S is provided to register a half cycle or pass onto a track section including the switch of operation of the thermal relay TR and a lock and thereby effect by other means to prevent a relay L is arranged to register the full cycle of movement thereof.
  • zation represents the lapse of time consumed it is proposed in accordance with this invention by an over and back operation of the relay TR, to provide a circuit means whereby a thermal ,11 accomplished i manner whi h in new time element is employed to enforce a lapse of b fully described, time between the operating of a signal to stop Considering how th t t relay M is 30 and the m v Of a associated track SWitChgized by the means above described, a circuit It i also Proposed to arrange Such thermal energizing the heating unit 4 is completed from means in a circuit wher y a power operat a terminal B of a source of energy, wire 12, movement thereof to O Position and p contact 13 of relay M, front point 14, wires 15 operated movement back to its starting position and 16, back point 7 and t t 13 of relay 3 is required to measure the time interval, thus de-energized wire 19 heating t 4 wire
  • heating unit 4 being thus energized raises the Other objects, purposes and characteristic featemperature of th l nt 1 higher th that, tunes of the invention w pp as the of 2 thereby bending both elements 1 and 2 to scr pt o t e progresses, during which refa left hand position until contact 7 engages erences will be made to the accompanying figure contact 9. of drawing.
  • the thermal relay TR in this left hand posi- T e Single figure of wing shows in a very tion now energizes relay S over the following 45 diagrammatic manner a time element and clrcircuit-beginning at a terminal B of a source cuit according to this invention.
  • a thermal relay TR is diagrammatically being energized interrupts the above traced enshown in the dotted rectangle and consists esergizing circuit for the heating unit 4 at its sentially of two bi-metallic elements 1 and 2, contact 18 and completes a stick circuit, form- 55 such, for example as in the application of J. E. lay S, from the terminal B, wires 12, contact 13 heating unit 4 in series with the windings of the relay S and consequently the resistance of the windings of the relay is made suiliciently high to limit the current in this circuit to a value whichis sufiicient to hold up the armature of the relay S but not sulrlcient to produce appreciable heating of the unit 4.
  • an energizing circuit for the heating unit, 5 is completed over the following circuit:-- beginning at the terminal B wire 12, contact 13 and front point ,14 of relay M energized, wires 15 and .16, front point 27 and contact 28 of re-' lay is energized, wires 29 and 30, back point 31 and contact 32 of relay L deenergized, wire 33, heating unit 5, wire 34, variable resistance unit 11, wire 21 to the opposite terminal C.
  • the heating unit 5 being thus energized raises the temperature of the element 2 higher thanthat of 1 thereby bending both elements backto their right hand starting position or to a position in which contact 8 engages contact l'o'thereby energizing relay L over the following circuit:-beginning at the terminal B wire 12, contact 13 and front point 14 of.relay M energized, wires 15 and 16, front point 27 and contact 28 of relay. S energized, wires 29 and 35, windings of relay L, wire 36, contacts 10 and 8,- through element 2, wire 34, variable resistance unit 11, wire 21 to, the opposite terminal C.
  • relay L With the relay L energized, .the energizing circuit for the heating unit 5 is interrupted at contact 32, and in as much as the normal de-energized position of the thermal relay TR holds the contact 8 engaging contact 10, the relay L is now maintained energized as long as relay M is energized.
  • Other contacts' may be included in relay L, such as 37, which may function to close or open circuits a predetermined time after the energization of the relay M.
  • this controlled circuit may be a common operating circuit for a switch machine such as shown in the previously mentioned application.
  • thermal relay has been provided in a circuit arrangement whereby contact means may be operated a predetermined time after the closing of an initiating circuit and such circuit arrangement measures this time interval by a cycle of operation which leaves the thermal relay in a condition for substantially the same time measurement during an immediate successive operation.
  • thermal relay employed in this invention is actuated by electrical power to both its operated position and back to its normal position, which coincidently compensates for atmospheric temperature variations and also provides a wider range of operating times inas much as both operating motions are adjustable by a variable resistance unit;
  • variable resistance units may be employed in the energizing circuits of the heating units 4 and 5 thereby obtain a Vernier adjustment on the operating time by individually adjusting its over and its back operating times.
  • the initiating relay M can, of course be any device either automatic or manual in operation and a part of any system for which the time element is adapted, as in centralized traffic control systems, etc.
  • a thermal relay having iii-metallic means operable to a normal and to reverse position, a first heating unit arranged to operate said bi-metallic means to said reverse position, a second heating unit arranged to operate said bi-metallic means to said normal position, a stick relay, an energizing circuit for said first heating element including a contact of said stick relay, an energizing circuit for said stick relayincluding contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a contact of said stick relay and a contact of said control relay, and an energizing circuit for said control relay including a contact of said stick relay and contact means of said thermal relay made in said normal position.
  • atime measuring device comprising two spaced thermo-responsive strips secured to a holding member at one end and anchored together at the other end, heating elements associated with each of said thermal responsive strips-so as to cause the strips to distinctively actuate contact means according to differential temperatures between'the strips, and circuit means arranged to successively energize said heating elements during a single operating cycle of said time measuring device.
  • thermo-responsive means arranged to distinctively actuate contacts according to differential temperatures in said thermo-responsive means
  • heating elements arranged to produce a dis-'- tinctive temperature differences in said thermoresponsive means and controlled means dependto reverse position, a first heating unit arranged to operate said thermal means to said reverse position, a second heating unit arranged to operate said thermal means to said normal position, a stick relay, an energizing circuit for said first heating element including a contact of said stick relay, an energizing circuit for said stick relay including contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a contact of said stick relay and a contact of said control relay, and an energizing circuit for said control relay including a contact of said stick relay and contact means of said thermal relay made in said normal position.
  • a thermal relay having oppositely arranged thermal elements, a heating unit for each element, a stick relay having an energizing circuit including a reverse contact of the thermal relay, and a control relay having an energizing circuit including a front point of the stick relay, and a normal contact of the thermal relay.
  • a thermal relay having thermal means operable to a normal and to reverse position, a first heating unit arranged to operate said thermal means to said reverse position, a second heating unit arranged to operate said thermal means to said normal position, a stick relay, an energizing circuit for said first heating element including a back contact of said stick relay, an energizing circuit for said stick relay including contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a front contact of said stick relay and a back contact of said control relay, and an energizing circuit for said control relay including a front contact or said stick relay and contact means of said thermal relay made in said normal position.
  • a time element circuit employing a thermal relay having opposed bi-metallic elements, operating units on each of said elements, energizing means for one of said operating units whereby said bi-metallic elements are operated to one position, a stick relay arranged to assume a position to register said position, energizing means for the other of said operating units whereby said bi-metallic elementsare operated back to normal position, a control relay, and means whereby said control relay assumes a position to register said normal position and said stick relay position.
  • a thermal relay comprising spaced oppositely arranged bi-metallic arms anchored at one end to a supporting member and rigidly interconnected at their free ends, contact means on said arms normally engaging a fixed back point to constitute an initial position and operable to engage a fixed front point, a heating unit on each 01 said arrxis, individual energizing circuits for each 01 said heating units arranged to cause the thermal relay to operate through one cycle only and return to its initial position, means in said energizing circuits for adjusting the electrical resistance thereof, control means, and means to control said control means only after operation through said cycle has occurred.
  • a time element circuit employing a thermal relay having oppositely arranged bimetallic elements, a heating unit on each of said elements for causing the thermal relay to assume reverse and normal positions, individual energizing circuits for said heating units including a variable resistance unit, a stick relay energized by a reverse position of said thermal relay, 9. control relay, and means for energizing said control relay when said stick relay is energized and said thermal relay is in a normal position.
  • thermo-sensitive elements having oppositely arranged thermo-sensitive elements, heating units on said elements, an en ergizing circuit for each unit, means to cause said circuits to successively energize said heating units, and means, responsive to the successive energizations of said heating units, to condition said time element circuit after a lapse of time.
  • thermo-sensitive elements which, when actuated cause the relay to make an over and back movement, heating units on said elements for actuating them, and energizing circuits arranged to successively energize said heating units and means to definitely and distinctively condition said time element circuit after a predetermined lapse of time equal to the time required for an over and back movement 01' said elements.
  • thermo-sensitive elements having oppositely arranged thermo-sensitive elements, heating units on said elements, energizing circuits for the elements, a stick relay at times in circuit with one of said units, a controlled relay dependcnt for its condition upon the stick relay condition and in turn controlling the time element circuit, means to cause said energizing circuits to successively energize said heating units, to thereby definitely condition said time element circuit by means of the controlled relay after a predetermined lapse of time.
  • a thermal relay having oppositely arranged thermo-sensitive elements, heating units on said elements, energizing circuits for the said elements for successively energizing the elements, a stick relay controlling one of said circuits, another relay arranged to control the other circuit and in turn controlled by the thermal relay and the stick relay and means whereby the other relay definitely conditions said time element circuit after a lapse of time dependent upon the operation of the thermal relay.

Description

J. "E. WILLING TIME ELEMENT CIRCUIT FOR TRAFFIC CONTROLLING SYSTEMS Filed July 20, 1931 INVENTOR eph EWHIH'I @(fl ATTORNEY gas 9 UNITED STATES PATENT OFFICE TIME ELEMENT CIRCUIT FOR TRAFFIC CONTROLLING SYSTEMS Joseph E. Willing, Rochester, N. Y., assignor to 1tlereral Railway Signal Company, Rochester,
Application July 20, 1931, Serial No. 551,931
14 Claims. (01. 175320) This invention relates to time element circuits Willing, Serial No. 463,903 filed June 26, 1930 and more particularly to a means for definitely which are oppositely mounted at one end on a conditioning a railway signalling circuit after suitable support, such as the member 3. These a predetermined lapse of time. elements 1 and 2 each carry electrical heating In certain railway signalling practices, a track units 4 and 5 respectively, which elements tend 60 switch and a signal governing movements over to deform in a direction indicated by the respecthis switch are controlled by an operator which tive small arrows thereon when heated above a obviously necessitates employing means to prenormal temperaure. The lower free ends of the vent the operators moving the track switch elements 1 and 2 are rigidly connected by a while the aforesaid signal is clear. It is also member 6, preferably of insulating material, and 65 necessary to prevent the operator after having these ends carry suitable contacts 7 and 8 which operated the signal to stop from immediately are respectively engagable with fixed resilient moving the track switch as such successive opcontacts 9 and 10. An adjustable resistance 11 erations might create a dangerous condition for may also be included in the common energizing 15 an oncoming train. circuit of the units 4 and 5 to vary the heating 70 To obviate this condition, a time interval is time of the elements. usually interposed which enforces that a defl- A relay M is also shown which may be either nite time elapse between the operating of the manually or automatically controlled in ac signal to stop and the moving of its associate cordance with traffic conditions as is clearly detr k w h, Whi h m is adequate for an onscribed in application above referred to. A 75 coming train to either stop clear of the switch stick relay S is provided to register a half cycle or pass onto a track section including the switch of operation of the thermal relay TR and a lock and thereby effect by other means to prevent a relay L is arranged to register the full cycle of movement thereof. operation thereof or, in other words, its energi- In view of the'above and other considerations, zation represents the lapse of time consumed it is proposed in accordance with this invention by an over and back operation of the relay TR, to provide a circuit means whereby a thermal ,11 accomplished i manner whi h in new time element is employed to enforce a lapse of b fully described, time between the operating of a signal to stop Considering how th t t relay M is 30 and the m v Of a associated track SWitChgized by the means above described, a circuit It i also Proposed to arrange Such thermal energizing the heating unit 4 is completed from means in a circuit wher y a power operat a terminal B of a source of energy, wire 12, movement thereof to O Position and p contact 13 of relay M, front point 14, wires 15 operated movement back to its starting position and 16, back point 7 and t t 13 of relay 3 is required to measure the time interval, thus de-energized wire 19 heating t 4 wire 20, l av the thermal means in a dit variable resistance unit 11, wire 21 to the opposubstantially the same time measurement imsite terminal C of the source of energy, The mediately after each operation. heating unit 4 being thus energized raises the Other objects, purposes and characteristic featemperature of th l nt 1 higher th that, tunes of the invention w pp as the of 2 thereby bending both elements 1 and 2 to scr pt o t e progresses, during which refa left hand position until contact 7 engages erences will be made to the accompanying figure contact 9. of drawing. In the drawing:- The thermal relay TR in this left hand posi- T e Single figure of wing shows in a very tion now energizes relay S over the following 45 diagrammatic manner a time element and clrcircuit-beginning at a terminal B of a source cuit according to this invention. of energy, wire 12, contact 13 and front point 14 The time element circuit shown in the accornof relay M energized, wires 15 and 22, winding panying figure of drawing is particularly appliof relay S, wires 23 and 24, contacts 9 and '1, cable to a railway trafilc controlling system such through the element 1, wire 20, variable re- 50 as is fully described in an application to R. M. sistance unit 11, wire 21 back to the opposite ter- Phinney filed June '26, 1930, Ser. No. 463,940. minal C of the source of energy. Relay S now A thermal relay TR is diagrammatically being energized interrupts the above traced enshown in the dotted rectangle and consists esergizing circuit for the heating unit 4 at its sentially of two bi-metallic elements 1 and 2, contact 18 and completes a stick circuit, form- 55 such, for example as in the application of J. E. lay S, from the terminal B, wires 12, contact 13 heating unit 4 in series with the windings of the relay S and consequently the resistance of the windings of the relay is made suiliciently high to limit the current in this circuit to a value whichis sufiicient to hold up the armature of the relay S but not sulrlcient to produce appreciable heating of the unit 4. v a
With the stick relay S held in this energized position, an energizing circuit for the heating unit, 5 is completed over the following circuit:-- beginning at the terminal B wire 12, contact 13 and front point ,14 of relay M energized, wires 15 and .16, front point 27 and contact 28 of re-' lay is energized, wires 29 and 30, back point 31 and contact 32 of relay L deenergized, wire 33, heating unit 5, wire 34, variable resistance unit 11, wire 21 to the opposite terminal C.
The heating unit 5 being thus energized raises the temperature of the element 2 higher thanthat of 1 thereby bending both elements backto their right hand starting position or to a position in which contact 8 engages contact l'o'thereby energizing relay L over the following circuit:-beginning at the terminal B wire 12, contact 13 and front point 14 of.relay M energized, wires 15 and 16, front point 27 and contact 28 of relay. S energized, wires 29 and 35, windings of relay L, wire 36, contacts 10 and 8,- through element 2, wire 34, variable resistance unit 11, wire 21 to, the opposite terminal C.
It will be noted that, with the relay L energized, .the energizing circuit for the heating unit 5 is interrupted at contact 32, and in as much as the normal de-energized position of the thermal relay TR holds the contact 8 engaging contact 10, the relay L is now maintained energized as long as relay M is energized. Other contacts'may be included in relay L, such as 37, which may function to close or open circuits a predetermined time after the energization of the relay M. For example, this controlled circuit may be a common operating circuit for a switch machine such as shown in the previously mentioned application.
It will now be seen that a thermal relay has been provided in a circuit arrangement whereby contact means may be operated a predetermined time after the closing of an initiating circuit and such circuit arrangement measures this time interval by a cycle of operation which leaves the thermal relay in a condition for substantially the same time measurement during an immediate successive operation.
It will also be seen that the thermal relay employed in this invention is actuated by electrical power to both its operated position and back to its normal position, which coincidently compensates for atmospheric temperature variations and also provides a wider range of operating times inas much as both operating motions are adjustable by a variable resistance unit;
In describing the present invention, no attempt has been made to point out the various alternate or optional features thereof or the different organizations or combinations that may be employed. For example, individual variable resistance units may be employed in the energizing circuits of the heating units 4 and 5 thereby obtain a Vernier adjustment on the operating time by individually adjusting its over and its back operating times. Also the initiating relay M can, of course be any device either automatic or manual in operation and a part of any system for which the time element is adapted, as in centralized traffic control systems, etc.
In other words, the particular embodiment of the present invention has been selected to facilitate in the disclosure thereof rather than to limit the number of forms which it may as- ,sume, and, it is to be further understood that various modifications, adaptations and alterations may be applied to the specific form shown to meet therequirements of practice, without in "any manner departing from the spirit or scope of the present invention except as limited by the appended claims.' I
Having thus described my invention, what I claim isz- 1. In a time element circuit, a thermal relay having iii-metallic means operable to a normal and to reverse position, a first heating unit arranged to operate said bi-metallic means to said reverse position, a second heating unit arranged to operate said bi-metallic means to said normal position, a stick relay, an energizing circuit for said first heating element including a contact of said stick relay, an energizing circuit for said stick relayincluding contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a contact of said stick relay and a contact of said control relay, and an energizing circuit for said control relay including a contact of said stick relay and contact means of said thermal relay made in said normal position.
2. In a time element circuit for railway signalling, atime measuring device comprising two spaced thermo-responsive strips secured to a holding member at one end and anchored together at the other end, heating elements associated with each of said thermal responsive strips-so as to cause the strips to distinctively actuate contact means according to differential temperatures between'the strips, and circuit means arranged to successively energize said heating elements during a single operating cycle of said time measuring device.
3. In a time element circuit for railway signalling, a time measuring device comprising thermo-responsive means arranged to distinctively actuate contacts according to differential temperatures in said thermo-responsive means,
heating elements arranged to produce a dis-'- tinctive temperature differences in said thermoresponsive means and controlled means dependto reverse position, a first heating unit arranged to operate said thermal means to said reverse position, a second heating unit arranged to operate said thermal means to said normal position, a stick relay, an energizing circuit for said first heating element including a contact of said stick relay, an energizing circuit for said stick relay including contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a contact of said stick relay and a contact of said control relay, and an energizing circuit for said control relay including a contact of said stick relay and contact means of said thermal relay made in said normal position.
6. In a timing circuit, a thermal relay having oppositely arranged thermal elements, a heating unit for each element, a stick relay having an energizing circuit including a reverse contact of the thermal relay, and a control relay having an energizing circuit including a front point of the stick relay, and a normal contact of the thermal relay.
7. In a time element circuit, a thermal relay having thermal means operable to a normal and to reverse position, a first heating unit arranged to operate said thermal means to said reverse position, a second heating unit arranged to operate said thermal means to said normal position, a stick relay, an energizing circuit for said first heating element including a back contact of said stick relay, an energizing circuit for said stick relay including contact means of said thermal relay made in said reverse position, a control relay, an energizing circuit for said second heating element including a front contact of said stick relay and a back contact of said control relay, and an energizing circuit for said control relay including a front contact or said stick relay and contact means of said thermal relay made in said normal position.
8. In a time element circuit employing a thermal relay having opposed bi-metallic elements, operating units on each of said elements, energizing means for one of said operating units whereby said bi-metallic elements are operated to one position, a stick relay arranged to assume a position to register said position, energizing means for the other of said operating units whereby said bi-metallic elementsare operated back to normal position, a control relay, and means whereby said control relay assumes a position to register said normal position and said stick relay position.
9. In a time element circuit for railway signalling, a thermal relay comprising spaced oppositely arranged bi-metallic arms anchored at one end to a supporting member and rigidly interconnected at their free ends, contact means on said arms normally engaging a fixed back point to constitute an initial position and operable to engage a fixed front point, a heating unit on each 01 said arrxis, individual energizing circuits for each 01 said heating units arranged to cause the thermal relay to operate through one cycle only and return to its initial position, means in said energizing circuits for adjusting the electrical resistance thereof, control means, and means to control said control means only after operation through said cycle has occurred.
10. In a time element circuit employing a thermal relay having oppositely arranged bimetallic elements, a heating unit on each of said elements for causing the thermal relay to assume reverse and normal positions, individual energizing circuits for said heating units including a variable resistance unit, a stick relay energized by a reverse position of said thermal relay, 9. control relay, and means for energizing said control relay when said stick relay is energized and said thermal relay is in a normal position.
11. In a time elementcircuit, a thermal relay having oppositely arranged thermo-sensitive elements, heating units on said elements, an en ergizing circuit for each unit, means to cause said circuits to successively energize said heating units, and means, responsive to the successive energizations of said heating units, to condition said time element circuit after a lapse of time.
12. In a short time element circuit, a thermal relay having oppositely arranged thermo-sensitive elements which, when actuated cause the relay to make an over and back movement, heating units on said elements for actuating them, and energizing circuits arranged to successively energize said heating units and means to definitely and distinctively condition said time element circuit after a predetermined lapse of time equal to the time required for an over and back movement 01' said elements.
13. In a time element circuit, a thermal relay having oppositely arranged thermo-sensitive elements, heating units on said elements, energizing circuits for the elements, a stick relay at times in circuit with one of said units, a controlled relay dependcnt for its condition upon the stick relay condition and in turn controlling the time element circuit, means to cause said energizing circuits to successively energize said heating units, to thereby definitely condition said time element circuit by means of the controlled relay after a predetermined lapse of time.
14. In a time element circuit, a thermal relay having oppositely arranged thermo-sensitive elements, heating units on said elements, energizing circuits for the said elements for successively energizing the elements, a stick relay controlling one of said circuits, another relay arranged to control the other circuit and in turn controlled by the thermal relay and the stick relay and means whereby the other relay definitely conditions said time element circuit after a lapse of time dependent upon the operation of the thermal relay.
JOSEPH E. WILLING.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2445450A (en) * 1943-06-11 1948-07-20 Westinghouse Electric Corp Electrical induction apparatus
US2525334A (en) * 1946-02-27 1950-10-10 Cook Electric Co Time-delay relay

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2445450A (en) * 1943-06-11 1948-07-20 Westinghouse Electric Corp Electrical induction apparatus
US2525334A (en) * 1946-02-27 1950-10-10 Cook Electric Co Time-delay relay

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