Improvements in Electric Railways Working on the Surface Contact System.
Year: 1899

page_text: Date of Application, 11th Oct., 1899-Accepted, 11th Nov., 1899
COMPLETE SPECIFICATION.
Improvements in Electric Railways Working on the Surface Contact
System.
I, ROBERT LUNDELL, of 527, West 34th Street, New York, United States of
America, Electrician, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:―
The present invention is directed to improvements in electric railways working
on the surface contact system, and has special reference to the type of such system
in which the sectional service conductors are automatically rendered active under-
neath an electric car by electromagnetic switches actuated by magnetic relays
which are successively operated by a powerful magnetic field generated beneath
the car and carried over the relays by the said car as it travels along.
The invention has for its chief objects to provide means whereby a requisite
time allowance may be given to the electromagnetic switches and to the relays
before they are called upon to perform their functions and to provide an efficient
magnetic circuit between the magnetic field carried underneath the car and the
magnetic relays, so that their operation may become infallible. A further object
of the invention is to reduce the cost of the system by the simple and effective
construction hereinafter described.
For a full and clear description of the invention, reference is made to the
accompanying drawings in which:
Figure represents a diagrammatic view of the electric and magnetic circuits
underneath the car. In this diagram the track is shown in plan, but the car
wheels, the motors, the current collecting shoe, the relays and the main magnets
are represented in side elevation, to facilitate a clear understanding of the mode
of operation.
Figure 2 is a plan of the track as it appears with its electric equipment.
Figure 3 shows a cross section of the road-bed taken on line X-X of Figure 2.
Figure 4 represents a longitudinal vertical section of a part of the middle
portion of the road-bed.
Figures 5, 6 and 7 are diagrammatic views of modified forms of the invention.
Referring particularly to Figure 1, F is a 500 volt feeder or main, w we are
branch feeders therefrom, leading to fixed contact points in electromagnetic
switching devices M'and M. 1, 3, are wires leading from opposite contact
points to sectional service conductors B, B. F¹ is a 50 volt feeder or main
with wires w, w, leading to the coils of the electromagnetic switches M MI, the
other ends of the coils being connected with wires, leading to fixed and
normally open contact points of magnetic relays contained in hermetically sealed
boxes D D. The movable contact members in the said boxes D D² are perma-
nently connected to the ground or return conductor, so that when contact is
established between the fixed and the movable members a current will flow
through the coils of the magnets M M', causing the switches to close and thus
establish connection between the sectional service conductors B3, B₁ and the
500 volt feeder. Supplementary magnetic relays of like construction (see D', D³)
TD Q77

page_text: are placed ahead of their respective electromagnets and connected by wires w8, 9,
wo, in parallel with the set of relays above referred to, in such manner that a
switch, for instance, can be closed by either one or both of the relays D¹ D².
R and Rare the track rails. TTT3 T4 are tie-rods which in this system
serve the additional purpose of completing a magnetic circuit between the contact
shoe S', the magnetic relays and the track rails. CC1 C2 Care pole extensions
for the magnetic relays D D 12 D3 such pole pieces or extensions being made
of thin sheet iron and imbedded in the asphalt pavement between the track rails
about an inch below the contact shoe S¹. These pole extensions serve the purpose
of collecting the magnetic lines of force from the shoe S₁ and conducting the
same into the vicinity of the free ends of the magnetic contact needles contained
in the relay boxes D D D thereby causing the said free ends to be attracted and
lifted upwards until the lower non-magnetic parts of the contact needles are
brought against the stationary contacts above referred to. The other ends of
said contact needles are, by means of additional downwardly projecting pole
extensions, in magnetic proximity to the tie rods above referred to (see Figure 4).
SS represent diagrammatically the magnetic cores of the contact shoe $¹,
around which the energizing coils M and M³ are wound, which coils receive their
energizing current from a small storage battery 14 carried on the car, or from
the main as the case may be.
The upper portions of said magnetic cores are in close proximity to the car
axles A and A¹, as indicated in Figure 1.
It will be noticed from inspection of the electric circuits leading from the
storage battery B to the contact shoe S¹, to the controllers on the car and to
the coils M2 M3 of the magnetic cores, that said cores will be magnetized either
by the battery current or by the main motor currents in such manner that their
lower ends will become north polarity and their upper ends south polarity. If
their lower ends are (as is the case) joined together by the steel shoe S¹, it follows
that the magnetic lines of force will travel in the following manner: From
cores S2 and S3 to the shoe St thence to the soft sheet iron pole extensions CC C
immediately underneath the same and so to the free ends of the magnetic needles
in the relay boxes through which needles the said lines of force travel to the
downwardly projecting pole extensions on the other side of the relay boxes and
to the tie rods T T2 and 13, where the said lines of force divide themselves,
one-half flowing one way to the track rail R and the other half flowing the
opposite way to the track rail R', and thence through the car wheels and car axles
to the upper ends of the magnetic cores S2 S3, thus completing the circuit.
As the car travels forward the magnetism remains constant in the contact
shoe S¹, the cores S2 S3, the car axles A. A' and the car wheels W WI, but it travels
along the rails in very much the same manner as the magnetism in an armature
core which is rotated in front of a pole piece. It will thus be understood that
the magnetic needles in the relay boxes with their thin annealed shect iron
pole extensions and tie rods are the only parts required to quickly receive their
magnetization, which parts, on account of their small dimensions and magnetic
properties, should respond to magnetic changes as readily as the laminated cores
of an alternating current transformer.
The operation of the electric circuits is as follows:-Assume the car is travelling
in the direction of the arrow (Figure 1) that is to say from left to right. In the
position of the car indicated in Figure 1, the sectional conductor B is made
active or alive by reason of the relay D being closed, which in turn has closed
the electromagnetic switch M in a manner previously described. Said sectional
conductor B is now supplying current from the 500 volt feeder to the motors and
if the current happens to be strong enough, also to the magnets M2 M3 and to
the battery B, charging the same as indicated on the diagram. The relays D¹
and 12 will also be closed and the electromagnetic switch M have had time to
close while the shoe S¹ travelled from the pole extension C¹ of relay D¹ to the pole

page_text: extension C of relay D². In other words the relay D₁ serves the purpose of
closing the switch M ahead of the contact shoe, so that the sectional conductor B¹
may be alive and ready for service before it has been reached by the travelling
contact shoe. Relay 12 will keep the switch closed while current is being
supplied from the sectional conductor B' in the same manner as shown by the
relay D, switch M, and sectional conductor B on the diagram.
Referring now to Figures 2, 3 and 4:-R and R' represent the two track
rails; B and B a couple of the sectional service conductors, which consist of short
pieces of ordinary Trail, as clearly shown by Figure 4. Said sectional conductors
are fastened to an insulating block or stringer, preferably made of asphalt-treated
wood built up in suitable sections which in turn are fastened to the cross-ties.
To the sides of this stringer are spiked asphalt-treated pieces of board standing
on end, as shown in Figure 3, the whole forming a continuous narrow trough in
which (in addition to the sectional conductors B B) the relay boxes D D1 D2 D3
with their pole extensions, wires www10 and 50 volt feeder F are contained.
This trough is filled with the best kind of insulating asphalt around the sectional
conductors and relay boxes, and, the top layer is made extra hard and smooth
The sectional
so as to form a good surface for the contact shoe to slide on.
conductors project only a very slight distance (about 1/4") above the asphalt sur-
face, just enough to insure good contact with the contact shoe. E are the
cast iron switch boxes with their covers E E¹ for containing the electromagnetic
switches. F is the 500 volt main and ww are the branch connections therefrom,
leading to normally open contact points in the switches. ¹³ are the wires
which connect the opposite contact points in the switches with the sectional
service conductors B B. Figure 4 shows clearly the relay boxes D and D
which are made of brass or other non-magnetic material and contain the imagnetic
needles N and N. The said needles are made of well annealed sheet iron (about
32" thick), and they are loosely hinged at points H H¹, at which points they are
in permanent electrical connection with the boxes D and D. Said boxes are in
turn connected to the ground or return conductor. The ends n* of the magnetic
needles are as previously stated in the vicinity of the pole-piece extensions C
and C and swing in close proximity to additional pole piece 'extensions J and J
inside the boxes when magnetized by the travelling contact shoe. The parts n
and of the needles are made of spring copper or other non-magnetic material
and are adapted to make electrical contact with the insulated carbon points K
and which are permanently connected to their respective switch coils as shown
on diagram Figure 1. At the hinged points of the needles N and N¹ are placed
other sheet iron pieces L and L' inside the boxes for the purpose of reducing the
magnetic reluctance between the needles and the downwardly projecting pole piece
extensions and t¹ on the other side of the relay boxes.
In Figure 5 is illustrated diagrammatically a modified form of the invention
in which the relays 113, polar extensions C C³ and the accompanying con-
ductors 10 for closing the circuit to the next sectional service conductor B¹
in advance of the current collecting shoe S₁ (as illustrated in Figure 1) are
dispensed with, the function attributable to said parts being accomplished in
this instance (Figure 5) by arranging the polar extensions CC, as shown, each
having a length approximating the distance between the switch boxes and the
sectional service conductors. The ends of said polar extensions are turned.
downward and rest against said boxes and in close proximity to the free ends n*
of the magnetizable needles enclosed therein.
With this modified form of the invention immediately after the front end of
the shoe S reaches the conductor B in passing from left to right in the direction
of the arrow, the polar extension C becomes magnetized and therefore acts upon
the magnetic needle in the box D2, thus causing the switch magnet M¹ to actuate
its switch and close the contacts between the branch feeders w³ ³ to the sectional
service conductor B¹, thereby affording a requisite time allowance for the action
of the switches, it being obvious that by reason of the magnetic relation of the

page_text: shoe S and long magnetic polar extension C lying parallel with and in close
proximity thereto, there will be given sufficient magnetic effect upon the latter
during the passage of the said shoe over it to actuate the switch next in advance,
under ordinary conditions of speed.
Figure represents diagrammatically another modified form of the invention,
in which the relays D D2 and polar extensions CC illustrated in Figure 1 are
dispensed with. The position of the relays D¹ D³ is reversed and their polar
extensions C1 C2 are laminated and extend toward the sectional conductors in
advance of the relays, as shown on the diagram. In this form a switch M³, for
instance, is given the requisite time allowance to close, by reason of the controlling
relay being placed ahead of the switch and its sectional conductor B. The
long polar extension C serves to keep the relay D¹ and the switch M' closed until
the contact shoe S¹ has left the sectional conductor B¹.
"
Instead of connecting the wires w and we to the main F1 as represented in
Figure 6, I may connect said wires to earth' as represented in Figure 7, in
which case the needles of the relays would be insulated and connected by a wire
to the said main F. This arrangement would avoid any danger of the current
leaking from the wires w8w through faulty insulation thereof or otherwise, and
completing the circuit of the switching magnets through earth without the needles
of the relays being operated by the car..
The wires w and in Figure 5 may also be connected to earth and the needles
of the relays be insulated and connected to the main F in an analogous manner
to that shewn in Figure 7, if desired.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. An electric railway system of the kind hereinbefore referred to, provided
with means substantially as described for causing each relay and switching
device to connect with the current main, the sectional service conductor next in
advance to the one supplying current to the car-motor, for the purpose specified.
2. The magnetizable car-shoe constructed and arranged to form with the tie-
rods, the wheels and axles of the vehicle and the rails, a circuit for the magnetic
lines of force, for the purpose specified.
3. The combination with the aforesaid relays of a magnetizable pole-piece or
magnetizable pole-picces, substantially as described and for the purposes specified.
4. An electric railway in which the relays and switching devices are constructed
and arranged to operate substantially as described with reference to the accom-
panying drawings for the purposes specified.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.