US761694A - Electric-railway system. - Google Patents

Electric-railway system. Download PDF

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US761694A
US761694A US17157203A US1903171572A US761694A US 761694 A US761694 A US 761694A US 17157203 A US17157203 A US 17157203A US 1903171572 A US1903171572 A US 1903171572A US 761694 A US761694 A US 761694A
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casing
armature
rail
railway
track
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US17157203A
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Charles H Murphy
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DAVID B HAND
GEORGE F GARRITY
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DAVID B HAND
GEORGE F GARRITY
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60MPOWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
    • B60M1/00Power supply lines for contact with collector on vehicle
    • B60M1/02Details
    • B60M1/08Arrangements for energising and de-energising power line sections using mechanical actuation by the passing vehicle

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  • My present invention relates to a novel electric-railway system of that type characterized by a trolley-line in the form of a third rail from which the current is taken by a trolley or shoe constituting the terminal of a local circuit on a'vehicle and including aimotor by means of which the vehicle is propelled.
  • Systems of this character have found a wide adoption, because of the inexpensive installation required; but they are open to several serious objections, the most prominentv of which is the danger arising from the exposure of the thirdrail, through which a current of high voltage is constantly passing. To the elimination of the danger mentioned and to the accomplishment of certain other.
  • my invention consists in forming the trolley-line or third rail in a series of comparatively short insulated sections which are normallyv dead, but which are arranged to be automatically connected one at a time with an insulated power-line or conductor which, while harmless on account of its insulation, may be still further protected in an underground conduit, if desired.
  • the several sections of the trolleyline or third rail are arranged to be connected with the power-line or conductor through the medium of a series of electromagnetic switches through which a p secondary or subcircuit is automatically closed by a vehicle-as, for instance, a car-as the latter approaches the sections with which the switches are associated.
  • Figure l' is a diagrammatic plan view of so much of a double-track railway as is necessary to illustrate the invention.
  • FIG. 2 is a horizontal sectional view of one of the electromagnetic switches, its casing, and connections.
  • Fig. 3 is an end view thereof, and
  • Fig. A is a side elevation of the same subjectmatter, shown partly in section.
  • the go and return tracks 1 and 2 of the railway are composed, as usual, of rails 3 and 1, the latter constituting the return-conductor of the power system.
  • the rails 3 are each composed of insulated sections 5, 6, and 7, the reason for which insulated'sectional form will presently appear.
  • the vehicle 12 (indicated diagram- .,matically in Fig. 1) is provided with a suitable motor 13, as usual, designed to take current from the third rail 8--as, for Instance,
  • the manner in which the power-line is protected is immaterial; but it is preferably provided with an insulating-covering .16 and for greater safety may be located below the level of the ground, either in a conduit or embedded in the earth. In fact, this power-line might, if desired, be elevated out of reach, the essential characteristic of this particular feature of the invention residing in the fact thatthe power-line is not exposed.
  • rlhe electrical connection of the third-rail sections with the power-line is effected by means of switches 17, 1,8, and 19, preferably of electromagnetic form, each switch being constructed substantially in the manner shown in Figs. 2, 3, and 4: of the drawings.
  • switches 17, 1,8, and 19 preferably of electromagnetic form, each switch being constructed substantially in the manner shown in Figs. 2, 3, and 4: of the drawings.
  • a casing 2O of any desired form and material are mounted, preferably adjacent to one end of the casing, a pair of contact-blocks 21, which may be formed at the inner ends of bolts 22, passed through insulating-bushings 23 in the opposite side walls of the casing and secured by nuts 24. Beyond the nuts 24 the bolts 22 are provided with jam-nuts 25, which serve to retain the ends of heavy branch wires 26 and 27.
  • the wire 26 is in electrical connection with a section of the third rail, while the wire 27 is similarly in electrical connection with the line-conducter 15, it being noted that the connections between the wires 26 and 27 and the contacts 21 are protected by housings 28, bolted to the casing 20.
  • the inner ends of the contact-blocks 21 are preferably beveled, as indicated at 29, and are designed to be engaged by a circuit-closing block 30, having its opposite ends correspondingly beveled and carried at the ends of a pair of supporting rods 31, passed through suitable guides 32 and secured to the armature 33 of an electromagnet 34.
  • the magnet 34 is preferably of the double-coil type, and the armature 33 thereof is provided with a stem 35, slidably received within a spring-barrel 36, bolted at one end to the casing 2O and inclosing a spring 37, bearing against the inner end of the stem 36 and exerting a constant tendency to retract the armature 33, and thus move the block 30 out of engagement with the contact-pieces 21.
  • a spring-barrel 36 bolted at one end to the casing 2O and inclosing a spring 37, bearing against the inner end of the stem 36 and exerting a constant tendency to retract the armature 33, and thus move the block 30 out of engagement with the contact-pieces 21.
  • the action of the spring 37 is augmented by apair of retracting-springs 38, secured tothe opposite side walls of the casing 2O and projecting inwardly into cooperative relation with the opposite ends of the armature 38.
  • each switch extends through one end of the casing 20, as shown in Fig. 2, one of these terminals-as, for instance, the terminal 39--being connected to an insulated section of the track-rail 3, and the other terminal-as, for instance, ICO-being connected to a feed-wire 41, common to all of the switches embraced by the system.
  • the wire 4l is supported by poles a, provided with insulating-caps, as usual.
  • This feed-wire is designed to carry a comparatively light current, which need only be sufiieient to energize the electromagnets of the switches.
  • a suitable source of electrical enorgy-as, for instance, a battery 42 -- is located at the power plant and is connected up in such a manner that the track-rail 4, which is not of insulated sectional form, will constitute a retur11-conductor for the secondary or switch-operating circuit.
  • This track-rail 4 is also related to the power-line 15 in a similar manner, so that said track-rail may constitute a common return for the primary or power circuit and also for the secondary or switch-operating circuit.
  • the main generator is indicated diagrammatically at (i in Fig. l, one side thereof being connected to both of the continuous return-rails and the other side having connection with the main power-line.
  • the operation of the system is as as follows: The several switches being normally open, the third rail is out of electrical connection with the power-line, and as the latter is not exposed a condition of absolute sa fety obtains. lf now a vehicle passes upon the end of one of the insulated track-rail sections as, for instance, the section (5 of the track-rail Sthis section of the track-rail is electrically connected with the track-rail 4, and a circuit is thus closed throughthe electromagnet of the switch 18. rlhe magnet being energized, the armature thereof is attracted, the circuitclosing block 30 is moved into engagement with the contact-block 21, and the section 1() of the third rail 8 is thus electrically connected with the power-line or conductor 15.
  • An ⁇ electric railway system including track-rails one of which is continuous and the other composed of insulated sections, a third 'rail composed of corresponding insulated secits opposite side connected to the continuous track-rail.
  • An electric-railway system including a double-track or two-sided railway, each side comprising a continuous track, a sectional track and a corresponding sectional third rail, a power-line common to both sides of the railway, electromagnetic switches interposed between the third-rail sections of each side and the power-line, a feed-wire common to the switches of both sides of the railway, a battery having electrical connection with the continuous tracks and with the feed-wire, wirin g connecting one terminal of each switchmagnet with the feed-wire, and wiring connecting the other terminal of said magnet with the sectional tracks of the railway.
  • An electromagnetic switch for railway systems comprising ⁇ a casing, a magnettherein, an armature provided with a stem, a barrel extending from the bottom of the casing for the reception of the stem, a spring inclosed within the barrel and bearing against the lower end of the stem, contact-blocks carried by the opposite walls of the casing, and a circuit-closing block supported by the armature and movable'into and out of engagement by the contact-blocks.
  • An electromagnetic switch for railway systems including a casing, a magnet therein, an armature for the magnet, acircuit-closing block connected with the armature, contactblocks provid ed with shanks extended through the opposite walls of the casing, and means exterior to the casing for retaining said shanks.
  • An 'electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their proximate ends beveled, a terminally beveled circuitclosing block, and an electromagnet mounted in the casing and having its armature connected with said block to move the same.
  • An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof, a circuit-closing block, an electroblock to move the same, means for attaching wires to the contact-blocks, and housings for said means located exterior to the casing.
  • An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their kapproximate ends beveled, a terminally-beveled circuit-closing block, van electromagnet mounted in the casing and having its armature connected with said circuit-closing block, a stem extended from the armature, a spring-barrel guiding the stem, an armature-retracting spring inclosed by the barrel, and means for attaching wires to the contact-blocks.
  • An electromagnetic switch for railway systems comprising a casing, contact-blocks secured to the opposite side walls thereof, a circuit-closing block, an electromagnet mounted in the casing and having its armature connected with said circuit-closing block, combined bu bombs and armature-retracting springs carried by the casing and disposed to be engaged by the opposite ends of the armature,
  • An electromagnetic switch for railway systems including a casing, fixed and movable switch elements therein, an electromagnet whose armature is provided with supportingrods carrying the movable switch element,"
  • An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their proximate ends beveled, a terminally-.beveled circuit-closing block, an electromagnet mounted in the casing and having its armature connected with said circuit-closing block, a stem extended from the armature, a spring-barrel guiding the stem, an armature-retracting springinclosed by the barrel, combined buffers and armature-retracting springs carried by the casing and disposed to be engaged bythe opposite ends of the armature, means for attaching wires to the contact-blocks, and housings for said means.

Description

PATENTED JUNE '1, 1904.
Y 1 h c. H. MURPHY. i
ELECTRIC RAILWAY sYslgrEM.
2 SHEETS-SHEET 2.
N0 MODEL.
UNO. 761,694.
UNITED STATES Patented June 7, 1904. j
PATENTI` OFFICE. i
CHARLESv H. MURPHY, OF SORANTON, PENNSYLVANIA, ASSIGNOR OF TWO-THIRDS TO DAVID B. HAND AND GEORGE F. VGARRITY, OF
scRANToN, PENNSYLVANIA.
ELECTRIC-RAILWAY SYSTEM.
SPECIFICATION forming part oi Letters Patent No. 761,694,v dated `June 7, 1904.
Application led September l, 1903. Serial No. 171,572. (No model.)
To a/ZZ whom it may concern:
Be itknown that I, OIIARLEs H. MURPHY, a citizen of the United States, residing at Scranton, 'in the county of Lackawanna and State of Pennsylvania, have invented va new and usefulElectric-Railway System, of which the following is a specification.
My present invention relates to a novel electric-railway system of that type characterized by a trolley-line in the form of a third rail from which the current is taken by a trolley or shoe constituting the terminal of a local circuit on a'vehicle and including aimotor by means of which the vehicle is propelled. Systems of this character have found a wide adoption, because of the inexpensive installation required; but they are open to several serious objections, the most prominentv of which is the danger arising from the exposure of the thirdrail, through which a current of high voltage is constantly passing. To the elimination of the danger mentioned and to the accomplishment of certain other.
objects, which will more fully appear, my invention consists in forming the trolley-line or third rail in a series of comparatively short insulated sections which are normallyv dead, but which are arranged to be automatically connected one at a time with an insulated power-line or conductor which, while harmless on account of its insulation, may be still further protected in an underground conduit, if desired.
In the preferred form of the invention illustrated in the accompanying drawings, hereinafter described in detail, and succinctly defined in the appended claims, the several sections of the trolleyline or third rail are arranged to be connected with the power-line or conductor through the medium of a series of electromagnetic switches through which a p secondary or subcircuit is automatically closed by a vehicle-as, for instance, a car-as the latter approaches the sections with which the switches are associated.
In said drawings, Figure l'is a diagrammatic plan view of so much of a double-track railway as is necessary to illustrate the invention. Fig.
2 is a horizontal sectional view of one of the electromagnetic switches, its casing, and connections. Fig. 3 is an end view thereof, and Fig. A is a side elevation of the same subjectmatter, shown partly in section.
Like characters are employed to designate corresponding parts in the several figures of the drawings. y f
The go and return tracks 1 and 2 of the railway are composed, as usual, of rails 3 and 1, the latter constituting the return-conductor of the power system. The rails 3 are each composed of insulated sections 5, 6, and 7, the reason for which insulated'sectional form will presently appear. Associated with each of the tracks 1 and 2 is a trolley-line in the form of a third rail 8, composed of sections 9 i1() 11, &c., completely insulated from each other. The vehicle 12 (indicated diagram- .,matically in Fig. 1) is provided with a suitable motor 13, as usual, designed to take current from the third rail 8--as, for Instance,
.through a shoe 14 in Asliding contact thereis preferably common to both tracks or sides`A 'f of the railway and is protected in a manner to absolutely preclude the possibility of danger. The manner in which the power-line is protected is immaterial; but it is preferably provided with an insulating-covering .16 and for greater safety may be located below the level of the ground, either in a conduit or embedded in the earth. In fact, this power-line might, if desired, be elevated out of reach, the essential characteristic of this particular feature of the invention residing in the fact thatthe power-line is not exposed.
rlhe electrical connection of the third-rail sections with the power-line is effected by means of switches 17, 1,8, and 19, preferably of electromagnetic form, each switch being constructed substantially in the manner shown in Figs. 2, 3, and 4: of the drawings. l/Vithin a casing 2O of any desired form and material are mounted, preferably adjacent to one end of the casing, a pair of contact-blocks 21, which may be formed at the inner ends of bolts 22, passed through insulating-bushings 23 in the opposite side walls of the casing and secured by nuts 24. Beyond the nuts 24 the bolts 22 are provided with jam-nuts 25, which serve to retain the ends of heavy branch wires 26 and 27. The wire 26 is in electrical connection with a section of the third rail, while the wire 27 is similarly in electrical connection with the line-conducter 15, it being noted that the connections between the wires 26 and 27 and the contacts 21 are protected by housings 28, bolted to the casing 20. The inner ends of the contact-blocks 21 are preferably beveled, as indicated at 29, and are designed to be engaged by a circuit-closing block 30, having its opposite ends correspondingly beveled and carried at the ends of a pair of supporting rods 31, passed through suitable guides 32 and secured to the armature 33 of an electromagnet 34. The magnet 34 is preferably of the double-coil type, and the armature 33 thereof is provided with a stem 35, slidably received within a spring-barrel 36, bolted at one end to the casing 2O and inclosing a spring 37, bearing against the inner end of the stem 36 and exerting a constant tendency to retract the armature 33, and thus move the block 30 out of engagement with the contact-pieces 21. Obviously the manner of mounting the electromagnet in the casing is not material and need not be described in detail. The action of the spring 37 is augmented by apair of retracting-springs 38, secured tothe opposite side walls of the casing 2O and projecting inwardly into cooperative relation with the opposite ends of the armature 38. When the armature 33 is attracted, these springs act as buffers to prevent violent impact of the moving parts; but when the current passing through the coils of the magnet ceases these springs 38 assist in the retraction of the armature, and thus insure the prompt movement of the circuit-closing block 30. The magnet- terminals 39 and 40 of each switch extend through one end of the casing 20, as shown in Fig. 2, one of these terminals-as, for instance, the terminal 39--being connected to an insulated section of the track-rail 3, and the other terminal-as, for instance, ICO-being connected to a feed-wire 41, common to all of the switches embraced by the system. Since the vehicle is not designed to take current from the feed-wire 41 by contact therewith, said wire may be located underground or overhead or disposed of in any desired manner. In Fig. l of thel drawings the wire 4l is supported by poles a, provided with insulating-caps, as usual. This feed-wire is designed to carry a comparatively light current, which need only be sufiieient to energize the electromagnets of the switches. A suitable source of electrical enorgy-as, for instance, a battery 42---is located at the power plant and is connected up in such a manner that the track-rail 4, which is not of insulated sectional form, will constitute a retur11-conductor for the secondary or switch-operating circuit. This track-rail 4 is also related to the power-line 15 in a similar manner, so that said track-rail may constitute a common return for the primary or power circuit and also for the secondary or switch-operating circuit.
In describing the system lV have addressed myself to one side only of the railway. lt will be understood, however, that both sides are identical and that both are supplied with power from the power-line l5 and that the switches of both sides of the railway are energized by current taken from the feed-line 41, either of the track-rails 4 constituting the return-conductor, accordingly as one side or the other of the railroad is considered.
The main generator is indicated diagrammatically at (i in Fig. l, one side thereof being connected to both of the continuous return-rails and the other side having connection with the main power-line.
Briefly, the operation of the system is as as follows: The several switches being normally open, the third rail is out of electrical connection with the power-line, and as the latter is not exposed a condition of absolute sa fety obtains. lf now a vehicle passes upon the end of one of the insulated track-rail sections as, for instance, the section (5 of the track-rail Sthis section of the track-rail is electrically connected with the track-rail 4, and a circuit is thus closed throughthe electromagnet of the switch 18. rlhe magnet being energized, the armature thereof is attracted, the circuitclosing block 30 is moved into engagement with the contact-block 21, and the section 1() of the third rail 8 is thus electrically connected with the power-line or conductor 15. As the contact-shoe 14 of the vehicle is in contact with this third-rail section, the power-circuit is closed through the lnotor ,13 on the vehicle and returns through the track-rail 4. Obviously the advance of the vehicle beyond the track-rail section 6 will effect th`e opening of that switch-operating circuit which has been closed, and the electrical connection lwtween the third-rail section 10 and the power-line will thus be broken by the opening of the switch 18.
Itis thought that from the foregoing the construction, operation, and many advantages of my system and the absolute safety thereof will be clearly comiirehended by those skilled in the art; but while the present embodiment of the invention appears at this time to be preferable l do not wish to he understood as limiting myself to the structural details defined. On the contrary, l desire to reserve the right to effect such changes, modifications, and variatlons of the illustrated lOO llO
structure as may fall fairly within the scope of the protection prayed.
What I claim is- 1. An `electric railway system including track-rails one of which is continuous and the other composed of insulated sections, a third 'rail composed of corresponding insulated secits opposite side connected to the continuous track-rail.
2. An electric-railway system including a double-track or two-sided railway, each side comprising a continuous track, a sectional track and a corresponding sectional third rail, a power-line common to both sides of the railway, electromagnetic switches interposed between the third-rail sections of each side and the power-line, a feed-wire common to the switches of both sides of the railway, a battery having electrical connection with the continuous tracks and with the feed-wire, wirin g connecting one terminal of each switchmagnet with the feed-wire, and wiring connecting the other terminal of said magnet with the sectional tracks of the railway.
3. An electromagnetic switch for railway systems comprising `a casing, a magnettherein, an armature provided with a stem, a barrel extending from the bottom of the casing for the reception of the stem, a spring inclosed within the barrel and bearing against the lower end of the stem, contact-blocks carried by the opposite walls of the casing, and a circuit-closing block supported by the armature and movable'into and out of engagement by the contact-blocks.
4. An electromagnetic switch for railway systems including a casing, a magnet therein, an armature for the magnet, acircuit-closing block connected with the armature, contactblocks provid ed with shanks extended through the opposite walls of the casing, and means exterior to the casing for retaining said shanks.
5. An 'electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their proximate ends beveled, a terminally beveled circuitclosing block, and an electromagnet mounted in the casing and having its armature connected with said block to move the same.
6. An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof, a circuit-closing block, an electroblock to move the same, means for attaching wires to the contact-blocks, and housings for said means located exterior to the casing.
7. An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their kapproximate ends beveled, a terminally-beveled circuit-closing block, van electromagnet mounted in the casing and having its armature connected with said circuit-closing block, a stem extended from the armature, a spring-barrel guiding the stem, an armature-retracting spring inclosed by the barrel, and means for attaching wires to the contact-blocks.
8. An electromagnetic switch for railway systems comprising a casing, contact-blocks secured to the opposite side walls thereof, a circuit-closing block, an electromagnet mounted in the casing and having its armature connected with said circuit-closing block, combined bu fiers and armature-retracting springs carried by the casing and disposed to be engaged by the opposite ends of the armature,
means for attaching wires to the contact-y blocks, and housings for said means.
9. An electromagnetic switch for railway systems including a casing, fixed and movable switch elements therein, an electromagnet whose armature is provided with supportingrods carrying the movable switch element,"
guides for said rods, and combined buffers and retracting-springs carried bythe casing and disposed to be engaged by the armature.
10. An electromagnetic switch for railway systems comprising a casing, contact-blocks detachably secured to the opposite side walls thereof and having their proximate ends beveled, a terminally-.beveled circuit-closing block, an electromagnet mounted in the casing and having its armature connected with said circuit-closing block, a stem extended from the armature, a spring-barrel guiding the stem, an armature-retracting springinclosed by the barrel, combined buffers and armature-retracting springs carried by the casing and disposed to be engaged bythe opposite ends of the armature, means for attaching wires to the contact-blocks, and housings for said means.
In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.
CHARLES H. MURPHY.
Witnesses:
JOHN H. SIGGERS, S. GEORGE TATE.
IOO
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2843701A (en) * 1955-11-28 1958-07-15 Jennings Radio Mfg Corp Vacuum relay
US2920162A (en) * 1956-01-03 1960-01-05 Jennings Radio Mfg Corp Vacuum relay

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2843701A (en) * 1955-11-28 1958-07-15 Jennings Radio Mfg Corp Vacuum relay
US2920162A (en) * 1956-01-03 1960-01-05 Jennings Radio Mfg Corp Vacuum relay

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