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

page_text: Date of Application, 20th Apr., 1899-Accepted, 19th Aug., 1899
Improvements in Electric Railways Working on the Surface
Contact System,
I, ROBERT LUNDELL, of No. 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:-
-
My invention relates to improvements in the type of electric railways working
on what is known as the surface contact system, in which short sectional service
conductors or contact pins located in the road-bed are normally disconnected
from the current feeder or main, but connected thereto in sequence as a car or
vehicle passes over them, and its objects are:-
First, to provide simple and efficient means for effecting the connection
between the sectional service conductors and the current feeder or main;
Second, to wholly embed or secure in the road-bed the operative parts so that
they may not be tampered with by unauthorized persons, and be rendered secure
against dangerous accidents to general traffic.
Third, to avoid any possibility of accidentally actuating the switching electro-
magnets through leaking or escaping currents from the current mains or the
branch feeders and sectional service conductors.
These objects are effected by and through the agency of a series of magnetically
controlled relays located in air and water tight switch boxes embedded in the
road-bed, and adapted to control the current flow from the current feeder or
nain to the branch feeders and sectional service conductors, by electromagnetic
switching devices actuated by an independent circuit, preferably of low voltage;
the armatures or needles of the relays being controlled in their movements by a
powerful magnetic field carried beneath the car and over the relays.
In order that my said invention may be fully understood and readily carried
into effect I will proceed to describe the same with reference to the accompany-
ing drawings which illustrates in cross section the road-bed of an electric rail-
way system, embodying the details of the invention diagrammatically illustrated,
together with means carried by the car for establishing or setting up a powerful
magnetic field over the enclosed magnetic relays as the car or vehicle advances.
R and R¹ represent the tram rails which are bonded together in the usual
way so as to constitute the return circuit for both the relay and propelling cur-
rents, said rails being supported upon cross ties T, as shown. B represents
one of a series of contact buttons or sectional service conductors secured within
protecting cups or casings B', bolted to the cross-ties T. S¹ represents a con-
tact skate or shoe carried by the car and connected to and through the pro-
pelling motor and to the wheels of the car (not shown) in the usual manner.
F represents the high voltage feeder or main connected to the station
generator at the power house and to tol are branch feeders running from the
current main F to the contact buttons or sectional service conductors B. el
and c³ are switching contacts in the branch feeder circuits and c switching

page_text: solenoid cores or armatures controlled by coils M¹, located in independent
branch feeders w² 3 of a low potential feeder F', and enclosed in air and water
tight switching boxes, and connected to an independent dynamo at the power
house, but of relatively much lower voltage than the power dynamo.
DD are air and water tight switch boxes of non-magnetic material located
just beneath the road-bed surface and preferably near the centre thereof. In
each of these boxes is enclosed a magnetic relay here shown as a pivoted mag-
netizable needle N¹ located in a plane at right angles to the road-bed with its
free or contact end normally at its lowest position, so that the circuit through
the relay coil M' is normally open. It will be apparent that the stationary or
magnetic relays enclosed in the switch boxes are connected in series relation
with the coils M¹ of the switch controlling electromagnets.
Each car or vehicle carries, beneath its floor and in close proximity to the
road-bed, a magnetic field composed of two long parallel iron pole pieces N
and S, slightly shorter than the car body. The said pole pieces are connected
together at two or more points by magnetic cores, wound with energizing coils M,
connected in multiple with an electrical generator, preferably a storage
battery B carried also by the car, the component parts being so proportioned
with relation to the actual relay work to be done that a powerful magnetic field
will be established between the poles N and S, and magnetic lines of force caused
to flow at right angles to the direction of motion of the car and in planes parallel
with the direction of movement of the relay needles or armatures.
The operation is as follows:-
already
When the circuit of battery B is closed through the coils of magnet or
magnets M, a powerful magnetic field is established beneath the car by the long
parallel bar pole pieces N and S and the lines of force flow at
right angles to the direction of movement of the car as
stated; consequently, the magnetizable relay needle N¹ in the switch
box D will tend to set itself in the plane of such lines of force, and
hence close the relay circuit, thereby conveying a low potential current of rea-
sonably small quantity (say one-half ampere) from the feeder F, through the
coils of the electromagnetic switch, thus causing its core e to be raised into
operative relation with the carbon switching contacts c¹². This effects circuit
connections between the high voltage or working feeder F and the sectional
service conductor B through the branch feeder. From the service con-
ductor B the current flows by the shoe S¹ and conductors (not shown) through
the motor on the car to the wheels and tram-rails R, R¹ back to the generator,
the same rails acting also as a return for the low voltage current through the
relay circuit 2 w³, as is obvious on inspection of the drawing.
As the car continues to travel the magnetic field between N and S is
advanced and the magnetic relay needles or armatures N' are operated in
sequence, and they successively assume their normal or disconnected posi-
tions, as said field moves from over them. It is apparent that by no possibility
can any leakage of current from the working feeder or branch feeder effect the
operation of the magnetic relays and that their operation can only be brought
about by the action of the magnetic field itself and the low voltage circuit.
I do not intend to limit myself to the specific details of construction herein
described with reference to the accompanying drawing.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I 5
claim is:
1. In an electric railway of the kind herein before referred to, the combination
with the electromagnetic switching devices for operatively connecting the sec-
tional service conductors in sequence to the current feeder or main, of stationary
relays for operating the electromagnetic switching devices, said relays being 5
included in circuit with a source of electrical energy of lower potential than

page_text: that of the current feeder or main, substantially as and for the purpose
described.
2. In an electric railway provided with stationary relays of the kind referred
to in the preceding claim, means carried by the car for magnetically actuating
the said stationary relays, substantially as described.
3. An electric railway in which the main circuit is brought into operation by
the action of stationary relays as the car moves over them, substantially as
described with reference to the accompanying drawing for the purpose specified.
Dated this 90th day of April 1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.