US2664472A - Automatic electric frog - Google Patents

Automatic electric frog Download PDF

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US2664472A
US2664472A US183874A US18387450A US2664472A US 2664472 A US2664472 A US 2664472A US 183874 A US183874 A US 183874A US 18387450 A US18387450 A US 18387450A US 2664472 A US2664472 A US 2664472A
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wire
tongue
main
current
operated
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US183874A
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Everett C Brown
Finan Thomas
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Cheatham Electric Switching Device Co
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Cheatham Electric Switching Device Co
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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
    • B60M1/12Trolley lines; Accessories therefor
    • B60M1/14Crossings; Points

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  • This invention relates to the operation of dirigible and track vehicles that are propelled by electricity received from overhead positive and negative trolley wires through trolley collectors carried by such vehicles and has particular application to trolley-bus systems wherein a"turnout is to be effected through the selection and operation of a frog tongue or tongues for guiding current collectors from through or main trolley wires on to branch wires in response to the longitudinal relation of one trolley collector to the other which occurs when making the turnout and to where the trolley collectors are oppositely disposed as when the trolley-bus is proceeding on the straight line of travel.
  • the main object of our invention is to eliminate the inherent disadvantages that'ha-ve been found in previous systems of this class and to provide a system that will operate through long periods of time with the desired definiteness.
  • Another object is to provide simplified apparatus for the type of operation referred to above that can be produced and delivered to the operating companies at a relatively low cost.
  • a further object of our invention is to provide automatic electrically operated frogs that are relatively easy to install and maintain for long periods of service without attention.
  • Figure 1 is a schematic illustration of the apparatus and control system for our automatic 2235961, March 25, 1941.;
  • Figure 2 is similarto Figure 1, however, modified to disclose theoperation of certain elements thatjprevent operationof the tongues of the frogs when the trolley-bus precedes on the straight through course of travel.
  • Figure -3 is an enlarged view of the type of contact device indicated in schematic illustration of the apparatus and control system in Figs.
  • the system includes main line and branch line .positive and negative current conductors or wires designated respectively by characters :P, Pl; N, i and that they are engaged respectively by current collectors 5, B of a trolley-bus, not shown.
  • Numerals l, 8 designate movable tongues at the turn-out point to provide a definite path of travel for 'thecollectors along the main line or to the branch line.
  • Springs .3 are arranged to bias normally the tongues for the collectors to traverse the main line or travel.
  • the tongues can be reversed so that the normal or rest position wili "be for the turn-out course of travel by using the springs oppositely to that illustrated.
  • Operatively attached to these tongues are plungers designated respectively 1A, BA that are operated by normally deenergized electromagnets 1M, 8M,
  • Adjacent the tongue of each frog is a contact device comprising swingable arm I ll located for movement by a current collector and pivoted in bearing H mounted on a wire by perch l2.
  • the free end l3 of each arm when operated by a collector from the rest position, as shown in Figure 1 adjacent the negative wire, has been moved to the operated position, whereupon it en ages and moves bell-crank M from one contact to the other.
  • the bell-cranks are pivoted in bearing I5 which are mounted on perches is attached and electrically connected to wire N or P.
  • Each bell-crank is the mechanical actuatorof the selector switch for the circuit that is to ap ly current to a solenoid for moving the tongue operativ'ly associated therewith and to interrupt the circuit to prevent operation of the solenoid on the other wire.
  • circuits and actuator in both figures are identical. and are organized so that only one frog can be operated at a given time, incident to one passage of the trolley-bus collectors through the system, when making a turn-out, however, incident to each through passage both contact devices are operated simultaneously and the circuits rendered deenergized.
  • the posi tive wire contact device feeds current through wire 20, bell-crank MP, wire 2 l, solenoid 88, wire 22, bell-crank MN, wire 23 to the negative wire, thereby pulling plunger 8A and its as sociated tongue from the straight line course of travel to the branch line of travel.
  • bell-crank MN has been moved from the rest position to the position as shown by current collector G, and that this collector has engaged and overlapped one of the tongues of the associated frog while arm It] remains raised for operating the said bell-crank thereby closing the circuit referred to above, after which operation it is returned to normal by the spring, SN; This condition continues until the collector has passed from arm I 0.
  • collector 5 will likewise operate bell crank MP, as shown in Figure 2, whereupon current flows from the positive wire to wire 28, bellcrank MP, wire 25, solenoid 7S, wire 25, bellcrank MN, wire 23, to the negative wire whereupon plunger IA responds to the magnetic force and moves the tongue in thepositive wire line so that the collector will then travel upon branch wire Pl.
  • the bell-cranks will be returned to the rest position by their related springs as stated above. It should be observed that while one solenoid is energized the circuit for the other solenoid has been opened.
  • both arms ill have actuated the bell-cranks from the rest position.
  • This operation opens the circuits of both solenoids as will be noted from the following: beginning with the positive wire; wire 20, bell-crank MP, wire 24, solenoid 1S, and wire 25 to an open switch. Beginning with the negative wire the circuit includes wire 26, bell-crank MN, wire 22, solenoid 88, wire 25 to an open switch. Since both these circuits are opened, as adverted to above, both solenoids will be inactive and the tongues remain in the rest position through the influence of spring S and that after the current collectors have passed. from arms Ill the bell-cranks will return't'o their respective rest positions and re-establish thecir cults to normal state.
  • Bell-crank MP in Figure 1 is shown in the rest position under influence of spring SP, while bellcrank l fiN is shown in the operated position against spring SN.
  • a switching system for a pair of current collectors mounted on a vehicle a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors,
  • yielding means for biasing each tongue for a selected position for guiding a current collector along the main wire, a solenoid for operating a mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing said solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith.
  • a switching system for a pair of current collectors mounted on a vehicle a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along one course of travel, electrically operated mechanism for moving each tongue for guiding a current collector to the other course of travel, control means for energizing the solenoid of each of said mechanisms comprising an electrical contact device located adjacent each tongue and operated by a current collector so that each or said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith.
  • a pair of main trolley wires or" opposite polarity and a branch wire for each main wire a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collec-- tor along the main wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices havin a selector switch operatively associated therewith for permitting and interrupting current flow to each solenoi
  • control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated Position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting and interrupting current flow to each solenoid; said contact devices located so that both will be operated to prevent current flow to both solenoids when engaged simultaneously by said collectors.
  • a switching system for a pair of current collectors mounted on a vehicle a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to uide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guidingmeans for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along the main Wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors Will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting current flow to one of said solenoids and preventing current
  • a pair of main trolley wires or" opposite polarity and a branch wire for each main wire a trolley frog at the intersection of each main and branch wire to uide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along th main wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting current flow to one of said solenoids and preventing current

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Current-Collector Devices For Electrically Propelled Vehicles (AREA)

Description

Dec. 29, 1953 E. c. BROWN ET AL 2,664,472
AUTOMATIC ELECTRIC FROG Filed Sept. 8, 1950 TAM/5L 9 INVENTORS.
51/522577 c. @Qmwv Mow/45 F/NA'N Patented Dec. 29, 1953 AUTOMATIC ELECTRIC Everett 0. Brown, Louisville, :Ky and Thomas .Finamrrovidenca lt. I., assignorsto Cheatham Electric Switching Device Company, .Incor-porat'ed, Louisville, Ky. a corporation :or Kentucky Application September 8, I950, "seriallilo. 183L874 (Cl. Till-38) This invention relates to the operation of dirigible and track vehicles that are propelled by electricity received from overhead positive and negative trolley wires through trolley collectors carried by such vehicles and has particular application to trolley-bus systems wherein a"turnout is to be effected through the selection and operation of a frog tongue or tongues for guiding current collectors from through or main trolley wires on to branch wires in response to the longitudinal relation of one trolley collector to the other which occurs when making the turnout and to where the trolley collectors are oppositely disposed as when the trolley-bus is proceeding on the straight line of travel. In turn out operations of this class, it has been learned that the longitudinal relative displacement of the trolley shoes is not always sufiiciently pronounced or definite to be depended upon, consequently, many efiorts have been made to overcome this condition. Such efforts have resulted in what now may be appraised as unnecessarily involved electrical and mechanical apparatus. An illustration of such a device is found 'in Patent 'No. 2,268,922 issued January 6, 1942 to one of the instant co-inventors. The following patents, directed to the solution of this problem disclose involved and complex electrical and/or mechanical apparatus when compared with that disclosed herein: 2,264,839, December 2, 1941; 2292.820, August 1-1, 1942 and 2,299,914. October 27, 1942. Although the designated systems have been produced, installed and used, each has been found wanting in some .respect or respects.
The main object of our invention is to eliminate the inherent disadvantages that'ha-ve been found in previous systems of this class and to provide a system that will operate through long periods of time with the desired definiteness.
Another object is to provide simplified apparatus for the type of operation referred to above that can be produced and delivered to the operating companies at a relatively low cost.
.A further obiect of our invention is to provide automatic electrically operated frogs that are relatively easy to install and maintain for long periods of service without attention. I
Other objects, advantages and features may appear from the accompanying drawings, the suh-ioined detailed description and appended claims.
In the drawin s:
Figure 1 is a schematic illustration of the apparatus and control system for our automatic 2235961, March 25, 1941.;
'2 electrically-operated frogs embodying the invention disclosed herein to explain the "operation thereof when the current collectors carried by a trolley-bus are on the verge of changing their course of travel from the main or through wires to branch wires.
Figure 2 is similarto Figure 1, however, modified to disclose theoperation of certain elements thatjprevent operationof the tongues of the frogs when the trolley-bus precedes on the straight through course of travel.
Figure -3 :is an enlarged view of the type of contact device indicated in schematic illustration of the apparatus and control system in Figs.
1 and 2.
Referring 'now in particular to Figure 1, it will be observed that the system includes main line and branch line .positive and negative current conductors or wires designated respectively by characters :P, Pl; N, i and that they are engaged respectively by current collectors 5, B of a trolley-bus, not shown. Numerals l, 8 designate movable tongues at the turn-out point to provide a definite path of travel for 'thecollectors along the main line or to the branch line. Springs .3 are arranged to bias normally the tongues for the collectors to traverse the main line or travel. Obviously, the tongues can be reversed so that the normal or rest position wili "be for the turn-out course of travel by using the springs oppositely to that illustrated. Operatively attached to these tongues are plungers designated respectively 1A, BA that are operated by normally deenergized electromagnets 1M, 8M,
the solenoids oi which are designated by is, 8S.
Adjacent the tongue of each frog is a contact device comprising swingable arm I ll located for movement by a current collector and pivoted in bearing H mounted on a wire by perch l2. The free end l3 of each arm, when operated by a collector from the rest position, as shown in Figure 1 adjacent the negative wire, has been moved to the operated position, whereupon it en ages and moves bell-crank M from one contact to the other. The bell-cranks are pivoted in bearing I5 which are mounted on perches is attached and electrically connected to wire N or P. Each bell-crank is the mechanical actuatorof the selector switch for the circuit that is to ap ly current to a solenoid for moving the tongue operativ'ly associated therewith and to interrupt the circuit to prevent operation of the solenoid on the other wire.
The circuits and actuator in both figures are identical. and are organized so that only one frog can be operated at a given time, incident to one passage of the trolley-bus collectors through the system, when making a turn-out, however, incident to each through passage both contact devices are operated simultaneously and the circuits rendered deenergized.
In the system as shown in Figure l, the posi tive wire contact device, as set, feeds current through wire 20, bell-crank MP, wire 2 l, solenoid 88, wire 22, bell-crank MN, wire 23 to the negative wire, thereby pulling plunger 8A and its as sociated tongue from the straight line course of travel to the branch line of travel. It should be noted that bell-crank MN has been moved from the rest position to the position as shown by current collector G, and that this collector has engaged and overlapped one of the tongues of the associated frog while arm It] remains raised for operating the said bell-crank thereby closing the circuit referred to above, after which operation it is returned to normal by the spring, SN; This condition continues until the collector has passed from arm I 0. Immediately following this operation, collector 5 will likewise operate bell crank MP, as shown in Figure 2, whereupon current flows from the positive wire to wire 28, bellcrank MP, wire 25, solenoid 7S, wire 25, bellcrank MN, wire 23, to the negative wire whereupon plunger IA responds to the magnetic force and moves the tongue in thepositive wire line so that the collector will then travel upon branch wire Pl. After both collectors havepassed from arms ill, the bell-cranks will be returned to the rest position by their related springs as stated above. It should be observed that while one solenoid is energized the circuit for the other solenoid has been opened.
During the straight through course of travel, as shown in Figure 2, both arms ill have actuated the bell-cranks from the rest position. This operation opens the circuits of both solenoids as will be noted from the following: beginning with the positive wire; wire 20, bell-crank MP, wire 24, solenoid 1S, and wire 25 to an open switch. Beginning with the negative wire the circuit includes wire 26, bell-crank MN, wire 22, solenoid 88, wire 25 to an open switch. Since both these circuits are opened, as adverted to above, both solenoids will be inactive and the tongues remain in the rest position through the influence of spring S and that after the current collectors have passed. from arms Ill the bell-cranks will return't'o their respective rest positions and re-establish thecir cults to normal state.
Bell-crank MP in Figure 1 is shown in the rest position under influence of spring SP, while bellcrank l fiN is shown in the operated position against spring SN.
The physical embodiment of our invention as disclosed herein is the form presently in commerce. Manifestly, the invention as illustrated and described is susceptible of modification without departing from the inventive concept, and right is hereby reserved to such modifications as fall within the scope of the appended claims.
W e claim:
1. In a switching system for a pair of current collectors mounted on a vehicle, a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors,
yielding means for biasing each tongue for a selected position for guiding a current collector along the main wire, a solenoid for operating a mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing said solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith.
2. In a switching system for a pair of current collectors mounted on a vehicle, a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along one course of travel, electrically operated mechanism for moving each tongue for guiding a current collector to the other course of travel, control means for energizing the solenoid of each of said mechanisms comprising an electrical contact device located adjacent each tongue and operated by a current collector so that each or said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith.
3. In a switching system for a pair of current collectors mounted on a vehicle, a pair of main trolley wires or" opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to guide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collec-- tor along the main wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices havin a selector switch operatively associated therewith for permitting and interrupting current flow to each solenoid.
' 4. In a switching system for a pair of current yielding means for biasing each tongue for a" selected position for guiding a current collector'- along the main wire, electrically operated mech-- anism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated Position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting and interrupting current flow to each solenoid; said contact devices located so that both will be operated to prevent current flow to both solenoids when engaged simultaneously by said collectors.
5. In a switching system for a pair of current collectors mounted on a vehicle, a pair of main trolley wires of opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to uide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guidingmeans for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along the main Wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors Will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting current flow to one of said solenoids and preventing current flow to the other solenoid.
6. In a switching system for a pair of current collectors mounted on a vehicle, a pair of main trolley wires or" opposite polarity and a branch wire for each main wire, a trolley frog at the intersection of each main and branch wire to uide a current collector on the vehicle either along the main wire or on to the branch wire, each frog provided with a movable tongue forming the guiding means for said current collectors, yielding means for biasing each tongue for a selected position for guiding a current collector along th main wire, electrically operated mechanism for moving each tongue for guiding a current collector from the main wire to the branch wire, control means for energizing the solenoid of each of said mechanisms comprising a contact device located adjacent each tongue and operated by a current collector so that each of said current collectors will retain the contact devices associated therewith in the operated position until the incident operating collector has engaged the tongue associated therewith; each of said contact devices having a selector switch operatively associated therewith for permitting current flow to one of said solenoids and preventing current flow to the other solenoid; said contact devices located so that they will be operated sequentially by the collectors on a vehicle when carried by a vehicle as it leaves a main course of travel for the branch course of travel.
EVERETT C. BROWN. THOMAS FINAN.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 787,856 Pfaffenbach et al. Apr. 18, 1905 2,053,965 Matthes Sept. 8, 1936 2,157,859 Moses May 9, 1939 2,268,922 Brown Jan. 6, 1942
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5913354A (en) * 1995-05-22 1999-06-22 Howmet Research Corporation Removal of ceramic shell mold material from castings

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US787856A (en) * 1904-01-13 1905-04-18 Rudolf Pfaffenbach Switch for suspended electric railways.
US2053965A (en) * 1934-12-05 1936-09-08 Ohio Brass Co Trolley wire frog
US2157859A (en) * 1936-08-26 1939-05-09 Westinghouse Electric & Mfg Co Control system for trolley frogs
US2268922A (en) * 1937-10-07 1942-01-06 Cheatham Electric Switching Device Co Automatic control for trolley frogs

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US787856A (en) * 1904-01-13 1905-04-18 Rudolf Pfaffenbach Switch for suspended electric railways.
US2053965A (en) * 1934-12-05 1936-09-08 Ohio Brass Co Trolley wire frog
US2157859A (en) * 1936-08-26 1939-05-09 Westinghouse Electric & Mfg Co Control system for trolley frogs
US2268922A (en) * 1937-10-07 1942-01-06 Cheatham Electric Switching Device Co Automatic control for trolley frogs

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5913354A (en) * 1995-05-22 1999-06-22 Howmet Research Corporation Removal of ceramic shell mold material from castings

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