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US1179293A - Selective relay. - Google Patents

Selective relay. Download PDF

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US1179293A
US1179293A US87319314A US1914873193A US1179293A US 1179293 A US1179293 A US 1179293A US 87319314 A US87319314 A US 87319314A US 1914873193 A US1914873193 A US 1914873193A US 1179293 A US1179293 A US 1179293A
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relay
contact
armature
coil
sector
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US87319314A
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Frank L Dodgson
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SPX Technologies Inc
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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
    • B61L29/00Safety means for rail/road crossing traffic
    • B61L29/08Operation of gates; Combined operation of gates and signals
    • B61L29/18Operation by approaching rail vehicle or train
    • B61L29/22Operation by approaching rail vehicle or train electrically
    • B61L29/226Operation by approaching rail vehicle or train electrically using track-circuits, closed or short-circuited by train or using isolated rail-sections

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  • FRANK L DODGSON, OF ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEW YORK. A CORPORATION OF NEW YORK.
  • This invention relates to a selective relay particularly applicable for controlling a highway crossing signal, together with other signals, such as block signals and approach indicators.
  • a signal such as a bell. a lamp. or a semaphore located on a highway which crosses a railroad track at grade.
  • Such crossing signals are usually controlled by relays controlled by the passage of trains.
  • Such signals are controlled from a track on which the traflic moves in both directions, it is necessary that they be operated by trains approaching from either direction when the trains are a certain distance from the highway, and it is advisable that they be discontinued as the train which causes them to operate passes the highway.
  • This device consists of two separate relays arranged so the operation of one relay mechanically or electrically governs the operation of the other.
  • the operating coils of each relay are each connected in bridge across the rails'of one of the insulated sections at the highway end of the'sections.
  • a battery is connected across the rails, so that the relays are normally energized.
  • the relay is thus denergized and operates by a dropping of its armature to close a circuit and thus cause the operation of the highway crossing signal.
  • the desired result is, therefore, effected when trains pass in either direction, and is accomplished as a result of the interlocking of the two relays.
  • Various schemes have been proposed to accomplish this result, and most of them consist of a compli cated arrangement ofpawls or similar devices-which prevent the relay which is the last to become denergized from completing the circuit through the crossing signal.
  • the primary object of this invention is the production of a device Which, when connected to the trackcircuit sections to which the ordinary interlocking relay is connected for controlling a highway crossing signal,
  • Figure 1 shows diagrammatically, a perspective view of a selective relay, electrical circuits through the rails of-a trackway and the circuit controlling a highway crossing signal.
  • Fig. 2 shows in their normal positions the parts of Fig. 1 which are required to control the circuit through the crossing signal.
  • Fig. 3 shows the same parts when one relay coil is energized and the other deenergized.
  • Fig. 4 shows the same parts when the first relay coil to become deenergized is again energized and the other.
  • Applicant has embodied the principle of his invention in a relay controlling the operation of a highway crossing signal as shown I in Fig'. 1 in which 1 and 2 indicate iron cores on which coils of wire 3 and 4 respectively are wound.
  • An armature 5 is attracted by the core 1 when an electric current flows through the coil 3 and an armature 6 is at tracted by core 2 when an electric current flows through coil 4.
  • Arms 7 and'8 are rigidly but insulatingly attached to the armatures 5 and 6 respectively.
  • Blocks 9 of insulating material secure the arm 7 to the armature 5 and blocks 10 and 11 of insulating material secure the arm 8 to the armature 6.
  • the armatures 5 and 6 are pivotally supported by being journaled on pins as 12, which are supported by brackets as 13.
  • Contact springs 14 and 15 are attached to the arm 7 in any suitable manner as by riveting as shown, and on the outer ends of the contact springs 14 and 15, contactors 16 and 17 are likewise attached.
  • Contact springs 18 and 19 are riveted to the arm 8 and contactors 20 and 21 are riveted to the outer ends of the contact springs 18 and 19.
  • An upper contact post 22 is permanently located so it makes electrical contact with contactor 16 when the contactor is raised by the movement of armature 5 due to the energization of coil 3.
  • An upper contact post 23 is similarly located with reference to contactor20 and makes contact therewith when the coil 4 is energized.
  • Lower contact post 24 is permanently located and makes contact with contactor 17 when the coil 3 becomes dei nergized and allows armature 5, arm 7, contact springs 14 and 15 and contactors 16 and 17 by the action of gravity. to drop until arrested and held by contactor 17 coming in contact with the lower contact post 24. which movement also causes contactor 16 to break contact with the upper contact post 22.
  • lower contact post 25 is located so it makes contact with contactor 21 when contactor 20 breaks contact with the upper contact post 23 when coil 4 becomes dei nergized.
  • the mechanisms so far described are in substance two separate electrical relays which may be controlled independently from two adjoining insulated sections of the rails of the track.
  • 26 and 27 indicate the two rails in one section of track and 28 and 29 indicate the two rails in the adjoining section. These two sections are insulated from each other by insulating rail joints 34 and 35, and are insulated from the other adjacent. sections by insulating joints 30. 31, and
  • the normally closed circuit of the relay coil 3 is as follows: Battery 36, rail 26. wire 41, coil 3, wire 67, and'rail 27 back to battery 36.
  • the circuit for relay coil 4 is as follows: Battery 37, rail 28, wire 39.
  • coil 4 wire 38, and rail 29 back to the battery 37. If a train moves on to rails 26 and 27 the current flows from battery 36 through rail 26, through the wheels and axles of the train to rail 27 and thence back to the battery 36, thus shunting coil 3 and deenergizingit. In like manner coil 4 is deenergized when a train moves onto the rails 28 and 29.
  • a metal plate 46 is rigidly secured to arm 7 by an insulating block 48 and metal plate 47 is rigidly connected to arm 8 by insulating block 49.
  • Wire 50 is electrically connected to the plate 46 in any appropriate manner as by a screw 52, and Wire 51 is likewise connected to plate 47 by screw 53.
  • a metal sector 54 positioned beneath plates 46 and 47 and journaled on pin 57, is normally held in the position shown in Fig. 1 and Fig. 2 by the action of a two arm spring 59, which is rigidly secured to an insulating support 60.
  • a lower projection 58 of seetor 54 is shaped so the two upright portions of spring 59 normally come in contact with the sides of the projection 58.
  • the signal continues to operate until all of the wheels of the train have moved off of rails 28 and 29, thereby allowing the relay coil connected to these rails to become energized, so that plate 47 breaks contact with the sector 54, interrupting the signal circuit, and stopping the signal.
  • both relay armatures assume their normal positions. If an approaching train first runs onto rails 26 and 27, the relay coil connected to these rails becomes de'cnergized and a. circuit is established through the crossing signal by plate 46 coming in contact with sector 54.
  • the e-nergization and, deenergization of coils 3 .and 4 not only governs the signal 63 in the manner described, but also go 'erns the contactors 16, 17, 20 and 21 in the ordinary and well known manner, so that any desired circuits may be controlled through their instrumentality. It being merely necessary to connect one terminal of the circuit to be controlled to the contactor and the other to either one or the other of the fixed contact posts, according to whether or not it is desired to have the controlled circuit opened or closed when the relay is energized: It is well known to those skilled in the railway signaling art how the contactors 1 0 16, 17, 20 and 21 and the posts 22, 23, 24 and 25, may be used to control the apparatuses used in railway signaling and therefore no explanation is needed.
  • a relay comprising two electromagnets, an armature controlled by each electromagnet, a circuit controller governed jointly by said armatures, and other circuit controlling devices governed by said arma- 120- other circuit controlling devices governed by said armatures.
  • a relay in combination: two electromagnets, an armature controlled by each electromagnet, a Contact attached to each armature and insulated therefrom, a movable contact arranged to 'coact with either of said first mentioned contacts when either of said armatures drops, the dropping'of either of said armatures causing said movable contact to move out of the path of the other contact, and other circuit controlling devices governed by said armatures.
  • a relay comprising two electromagnets, an armature controlled by each electromagnet, a contact attached to each armature and insulated therefrom, a movable contact member arranged to coact with either of said first mentioned contacts, and resilient means for conducting current to said movable contact member and for returning said movable contact member to its normal position.
  • a relay comprising two electromagnets, an armature controlled by each electromagnet, a member of insulating material attached to each armature, a contact secured to the lower face of each member, and a movable contact arranged to coact with either of said first mentioned contacts when either of said armatures drops, the dropping of either of said armatures moving said movable contact out of the path of the contact on the other armature.
  • a relay comprising two electromagnets, an armature controlled by each electromagnet, a contact attached to each armature and insulated therefrom, an oscillatable contacting member pivotally mounted and arranged to coact with either of said first mentioned contacts, the dropping of either armature moving said contact member out of the path of the contacton the other armature, and resilient means for conducting current to said oscillatable contacting member and for returning said oscillatable contacting member to its normal position.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Train Traffic Observation, Control, And Security (AREA)

Description

F. L. DODGSON.
SELECTIVE RELAY.
APPLICATION man NOV- 20. 1914.
Patented Apr. 11, 1916.
WITNESSES INVENTOR A TTORNEY UNITED STATES PATENT OFFICE.
FRANK L. DODGSON, OF ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEW YORK. A CORPORATION OF NEW YORK.
SELECTIVE RELAY.
Specification of Letters Patent.
Patented Apr. 11, 1916.
Application filed November 20, 1914. Serial No. 873,193.
I '0 all whom it may concern:
Be it known that I, FRANK L. DODGSON, a citizen of the United States, and a resident of the city of Rochester, in the county of Monroe and State of New York, have invented a new and useful Selective Relay, of which the following is a specification.
This invention relates to a selective relay particularly applicable for controlling a highway crossing signal, together with other signals, such as block signals and approach indicators. i
It is often required to control a signal, such as a bell. a lamp. or a semaphore located on a highway which crosses a railroad track at grade. Such crossing signals are usually controlled by relays controlled by the passage of trains. \Vhen such signals are controlled from a track on which the traflic moves in both directions, it is necessary that they be operated by trains approaching from either direction when the trains are a certain distance from the highway, and it is advisable that they be discontinued as the train which causes them to operate passes the highway. It is the usual practice on single track railroads to operate such signals by means of two adjoining insulated sections of track, each extending about two thousand feet, one on either side of the highway. An interlocking relay controlled by these sections is generally used to directly control the operation of the signal. This device consists of two separate relays arranged so the operation of one relay mechanically or electrically governs the operation of the other. The operating coils of each relay are each connected in bridge across the rails'of one of the insulated sections at the highway end of the'sections. At the other endof each of the sections a battery is connected across the rails, so that the relays are normally energized. As a train approaches the highway it moves on to the battery end of a section, thus causing the relay connected to that section to be shunted by the circuit of low resistance established through the wheels and axles of the train. The relay is thus denergized and operates by a dropping of its armature to close a circuit and thus cause the operation of the highway crossing signal. The signal continues just so long as any {art of the train is on the section. When the head end of the; train moves onto the section on the other side of the highway the relay con nected to that section also becomes deenerglzed. When the rear end of the train clears the first section entered the relay that operated first becomes energized and the other relay remains denergized, and the, signal is discontinued notwithstanding the fact that the second relay to become denergized remains deenergized, and also notwithstanding the fact that if the train had approached the highway from the opposite direction the second relay above mentioned would have been the first to become denergized", and would in such case have operated the signal. Th s same mode of operation results if a train approaches the crossing from either direction. The desired result is, therefore, effected when trains pass in either direction, and is accomplished as a result of the interlocking of the two relays. Various schemes have been proposed to accomplish this result, and most of them consist of a compli cated arrangement ofpawls or similar devices-which prevent the relay which is the last to become denergized from completing the circuit through the crossing signal.
These relays, due to "their mechanical features, are subject to certain failures which are undesirable. Furthermore, the track sections which are used to control the crossing signals are often used to control block signals or approach indicators, and it is furthermore, for the sake of economy, desirable to accomplish such control through the contacts of the'interlocking relay, but the construction of these interlockin relays is such that they cannot be used or this purpose, because the armature of the second relay to become denergized is prevented from falling through the same distance it would have fallen if it had been the first. to become denergized, consequently it does not touch the so-called'ffback contact?, and so complete a circuit for governing the block signals or approach indicators, and even if it did touch the back contact it would not bear forcibly enough thereon to form a proper contact because it would be partially supported by the interlocking mechanism governed by the armature of the other relay. The primary object of this invention is the production of a device Which, when connected to the trackcircuit sections to which the ordinary interlocking relay is connected for controlling a highway crossing signal,
will perform not only the functions which are now performed by the ordinary interlocking relay, but others which the interlocking relay does not now perform.
Other objects and advantages will appear as the description of the invention progresses and the novel features of theinvention will be particularly pointed out in the appended claims.
In describing the invention in detail, reference will be had to the accompanying drawing, on which like characters of refer ence refer to like parts, and in which applicant, has shown a preferred form of mechanism embodying the principle of his invention, and in which:
Figure 1 shows diagrammatically, a perspective view of a selective relay, electrical circuits through the rails of-a trackway and the circuit controlling a highway crossing signal. Fig. 2, shows in their normal positions the parts of Fig. 1 which are required to control the circuit through the crossing signal. Fig. 3, shows the same parts when one relay coil is energized and the other deenergized. Fig. 4, shows the same parts when the first relay coil to become deenergized is again energized and the other.
relay coil remains deenergized.
Applicant has embodied the principle of his invention in a relay controlling the operation of a highway crossing signal as shown I in Fig'. 1 in which 1 and 2 indicate iron cores on which coils of wire 3 and 4 respectively are wound. An armature 5 is attracted by the core 1 when an electric current flows through the coil 3 and an armature 6 is at tracted by core 2 when an electric current flows through coil 4. Arms 7 and'8 are rigidly but insulatingly attached to the armatures 5 and 6 respectively. Blocks 9 of insulating material secure the arm 7 to the armature 5 and blocks 10 and 11 of insulating material secure the arm 8 to the armature 6. The armatures 5 and 6 are pivotally supported by being journaled on pins as 12, which are supported by brackets as 13. Contact springs 14 and 15 are attached to the arm 7 in any suitable manner as by riveting as shown, and on the outer ends of the contact springs 14 and 15, contactors 16 and 17 are likewise attached. Contact springs 18 and 19 are riveted to the arm 8 and contactors 20 and 21 are riveted to the outer ends of the contact springs 18 and 19.
An upper contact post 22 is permanently located so it makes electrical contact with contactor 16 when the contactor is raised by the movement of armature 5 due to the energization of coil 3. An upper contact post 23 is similarly located with reference to contactor20 and makes contact therewith when the coil 4 is energized. Lower contact post 24 is permanently located and makes contact with contactor 17 when the coil 3 becomes dei nergized and allows armature 5, arm 7, contact springs 14 and 15 and contactors 16 and 17 by the action of gravity. to drop until arrested and held by contactor 17 coming in contact with the lower contact post 24. which movement also causes contactor 16 to break contact with the upper contact post 22. In like manner lower contact post 25 is located so it makes contact with contactor 21 when contactor 20 breaks contact with the upper contact post 23 when coil 4 becomes dei nergized. The mechanisms so far described are in substance two separate electrical relays which may be controlled independently from two adjoining insulated sections of the rails of the track.
26 and 27 indicate the two rails in one section of track and 28 and 29 indicate the two rails in the adjoining section. These two sections are insulated from each other by insulating rail joints 34 and 35, and are insulated from the other adjacent. sections by insulating joints 30. 31, and The The normally closed circuit of the relay coil 3 is as follows: Battery 36, rail 26. wire 41, coil 3, wire 67, and'rail 27 back to battery 36. The circuit for relay coil 4 is as follows: Battery 37, rail 28, wire 39.
coil 4, wire 38, and rail 29 back to the battery 37. If a train moves on to rails 26 and 27 the current flows from battery 36 through rail 26, through the wheels and axles of the train to rail 27 and thence back to the battery 36, thus shunting coil 3 and deenergizingit. In like manner coil 4 is deenergized when a train moves onto the rails 28 and 29.
A metal plate 46 is rigidly secured to arm 7 by an insulating block 48 and metal plate 47 is rigidly connected to arm 8 by insulating block 49. Wire 50 is electrically connected to the plate 46 in any appropriate manner as by a screw 52, and Wire 51 is likewise connected to plate 47 by screw 53. A metal sector 54 positioned beneath plates 46 and 47 and journaled on pin 57, is normally held in the position shown in Fig. 1 and Fig. 2 by the action of a two arm spring 59, which is rigidly secured to an insulating support 60. A lower projection 58 of seetor 54 is shaped so the two upright portions of spring 59 normally come in contact with the sides of the projection 58. When the sector is caused to turn in either direction one of the upright portions of spring 59 exerts a pressure on the side of projection 58 as shown in Fig. 3 and Fig. 4 tending to cause the sector to return to its normal posiin this position and the coil 3 becomes deenergized, and the relay armature 5 operates by gravity, plate 46 will move to the position shown in dotted lines in Fig. 3, but without coming in contact with sector 54. In like mannerplate 46 may be brought in contact with sector 54, when coil 3 becomes de' nergized, and'coil 4 is energized,
causing sector 54 to be so positioned that the relay armature 6 may fall without coming in contact with sector 54.
If after 'the relay coil controlled by current from battery 37 becomes de'nergized, causing sector 54 to move into the position shown in Fig. 3, the relay coil controlled by current from battery 36 becomes de'elnergized so that the plate 46 and the insulated block48 take the positions shown in dotted lines in Fig. 3, then if the relay coil controlled by current-from the battery 37 becomes energized, sector 54 is released by plate 47 and spring 59 causes sector 54 to turn toward its normal position. The sector cannot, however, reach its normal position because its motion is arrested by'the corner 55 of the sector coming in contact with the insulated block 48, as shown in Fig. 4. Vhen the relay controlled by cur.- rent from battery 36 is then energized, insulated block 48 and plate 46 are raised, a1- lowing sector 54 to return to its normal position.
When a train approaches the highway located say at the insulating joints 34 and 35, and runs on torails28 and 29 the relay coil under the control of this section of track is de'energized, and a circuit through the crossing signal is established as follows Battery 61, wire 62, signal 63, wire 64, wire 51, plate 47 sector 54, spring 59 and wire 65 back to the battery. Current flowing in this circuit causes'the' operation of the signal. When the head end of the same train runs onto the rails 26 and 27, the relay coil connected to these rails becomes deenergized, and plate 46 falls but does not come in contact with the sector 54 because it is not in proper position. The signal, however, continues to operate until all of the wheels of the train have moved off of rails 28 and 29, thereby allowing the relay coil connected to these rails to become energized, so that plate 47 breaks contact with the sector 54, interrupting the signal circuit, and stopping the signal. When the train has passed off of the rails 26 and 27 both relay armatures assume their normal positions. If an approaching train first runs onto rails 26 and 27, the relay coil connected to these rails becomes de'cnergized and a. circuit is established through the crossing signal by plate 46 coming in contact with sector 54.
It is evident with trains moving in either direction the signal will operate as long as the relay coil which was first to become deenergized, remains deenergized, regardless of whether the other relay coil is deenergized or not, and as soon as the relay first to become deenergized again becomes energized the operation of the signal will be discontinued, whether the other relay coil is deenergized or energized. \Vhen the train has entirely cleared the insulated sections the relay coils both become energized.
The e-nergization and, deenergization of coils 3 .and 4 not only governs the signal 63 in the manner described, but also go 'erns the contactors 16, 17, 20 and 21 in the ordinary and well known manner, so that any desired circuits may be controlled through their instrumentality. It being merely necessary to connect one terminal of the circuit to be controlled to the contactor and the other to either one or the other of the fixed contact posts, according to whether or not it is desired to have the controlled circuit opened or closed when the relay is energized: It is well known to those skilled in the railway signaling art how the contactors 1 0 16, 17, 20 and 21 and the posts 22, 23, 24 and 25, may be used to control the apparatuses used in railway signaling and therefore no explanation is needed.
Although I have particularly described 1 the construction of one physical embodiment of my invention, and explained the operation and principle thereof; nevertheless, I
' desire to have it understood that the form selected is merely illustrative, but doesnot 1 exhaust the possible physical embodiments of the idea of means underlying my invention. I
What I claim as new and desire to secure. by Letters Patent of the United States, is:
1. A relay comprising two electromagnets, an armature controlled by each electromagnet, a circuit controller governed jointly by said armatures, and other circuit controlling devices governed by said arma- 120- other circuit controlling devices governed by said armatures.
3. In a relay, in combination: two electromagnets, an armature controlled by each electromagnet, a Contact attached to each armature and insulated therefrom, a movable contact arranged to 'coact with either of said first mentioned contacts when either of said armatures drops, the dropping'of either of said armatures causing said movable contact to move out of the path of the other contact, and other circuit controlling devices governed by said armatures.
4;. A relay comprising two electromagnets, an armature controlled by each electromagnet, a contact attached to each armature and insulated therefrom, a movable contact member arranged to coact with either of said first mentioned contacts, and resilient means for conducting current to said movable contact member and for returning said movable contact member to its normal position.
5. A relay comprising two electromagnets, an armature controlled by each electromagnet, a member of insulating material attached to each armature, a contact secured to the lower face of each member, and a movable contact arranged to coact with either of said first mentioned contacts when either of said armatures drops, the dropping of either of said armatures moving said movable contact out of the path of the contact on the other armature.
G. A relay comprising two electromagnets, an armature controlled by each electromagnet, a contact attached to each armature and insulated therefrom, an oscillatable contacting member pivotally mounted and arranged to coact with either of said first mentioned contacts, the dropping of either armature moving said contact member out of the path of the contacton the other armature, and resilient means for conducting current to said oscillatable contacting member and for returning said oscillatable contacting member to its normal position. I
FRANK L. DODGSON. Witnesses F. BALCOREN, SOPHIE LEVIN.
Copies '0: this -patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.
US87319314A 1914-11-20 1914-11-20 Selective relay. Expired - Lifetime US1179293A (en)

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