Improvements in Electrical Railway Systems
Year: 1885

page_text: .
I, JAMES FRANCIS MCLAUGHLIN of No 224 South Third Street in the City of
Philadelphia State of Pennsylvania 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 consists of certain Improvements in Electrical Railway Systems
the main object of my Invention being to provide for the running of a larger
number of cars on a circuit with the motors in multiple arc than is possible in the
ordinary way.
In the accompanying drawings
Figure 1 is a diagram illustrating my Improvement.
Figure 2. is an enlarged view of a contact wheel which may be used in carrying
out my Invention.
Figure 3 is a view of a modified form of wheel.
Figure 4 is a view illustrating how the contact wheel may be applied.
Figure 5 is a diagram illustrating a further modification.
Figure 6 is a vertical section of a construction which may be employed in
carrying out my Invention, and
Figure 7 is a perspective view of part of the same.
Referring to the diagram Figure 1, A and B, represent the main conductors of
the line, which may be the ordinary track rails or conductors laid alongside thereof,
or in a conduit between the track rails, and G is the stationary generator supplying
the current to run the motors on the various cars, one of the conductors A, B,
forming the outward conductor, while the other is the return conductor.
M, M, represent the motors in the various cars seven being illustrated in the
diagram and C, C¹, represent the contacts, which in this case are shewn as being in
the form of wheels, running in connection with the conductors A, B.
The number of cars which can be run in such a system of multiple arc, is
necessarily limited by practical considerations, but in order to increase this limit
without increasing the size of the conductors, I supply the current from the main
conductor to each motor in its derived circuit intermittently, but at such rapid
intervals as not to interfere with the practically continuous operation of the motor,

page_text: and the devices whereby the current is fed intermittently to the several motors are
so arranged relatively to each other that the current will not at any specific
moment be supplied to the entire number of motors on the section. In other
words, some of the motors will be out of circuit, while others are in circuit.
As a means of carrying this into practical effect, one or both of the contact
wheels C, C, may be constructed so as to make an interrupted connection with the
said conductors A, B, by building the wheel up with alternating metallic and
insulating segments, as illustrated in Figure 2, or by notching the wheel, as shewn
in Figure 3, so that as the car travels on the track, and the wheel C, for instance,
travels in contact with the conductor A, the motor of the car will receive an
intermittent current from the conductor A, and in practical operation the contact
wheel C of the several cars will occupy different relative positions, so that while
some of them at any one moment would be making contact with the electrical
conductor A, others would be out of contact therewith, and although the number
of motors out of circuit at specific different times might vary to some extent, yet
for practical purposes, that would not seriously interfere with their operation.
The rapidity of the making and breaking of the current supplied to each motor
will prevent its intermittent character from interfering with its operation.
Other means may be provided for intermitting the current supplied to each motor
without interfering with the current on the main conductor. For instance, the
interrupting wheel D, illustrated in Figure 4, may be placed at any other point in
each derived circuit instead of employing a segmental contact wheel, suitable
brushes E, E¹ being provided one to bear on the compound portion of the wheel,
and the other on the metallic ring or hub d.
This circuit breaker may be adapted to be operated by a belt f, from any moving
portion of the car or motor, or, if desired, may be driven continuously from clock-
work mechanism g, or other motive power. In the latter case, the circuit breakers
on the several cars may be timed to run in concert or synchronously, so that a
certain number of motors on the section or circuit will always be out of circuit at
any time that the others are in circuit.
In practical operation, where one of the contact wheels C is used to interrupt
the circuit, it will be necessary to provide for the contingency of the car stopping,
so as to leave the wheel with the insulated portion thereof in contact with the
conductor, as illustrated in Figure 5. In such case, a supplementary contact c may
be provided with a. conductor 3 and switch or key 4, forming the branch circuit
leading to the motor, which may be closed by the operator at any time to supply
the current to the motor when desired.
In carrying my invention into practical effect, I prefer to use the construction
illustrated in Figures 6 and 7, in which F is a conduit which is laid centrally
between the ordinary car tracks and containing on its opposite side walls longi
tudinal insulating bars T, carrying the conductors A, B, in this case preferably of
flat copper strips.
I prefer to form the conduit F of two parts with an overlapping joint f' at the
bottom, as illustrated in Figure 6, and the conduit thus made is bolted to the
transverse sleepers.
H is the underside of a car, and from this is suspended the compound bar J
which carries at its lower end, within the conduit, the contact wheels C C adapted
to run in contact with the conductors A, B.
This bar J as illustrated in Figure 7, consists of two metallic plates j, j', with an
intervening plate of insulating material, and the upper ends of the plates are
flanged and bolted to spring arms K which are bolted to the underside of the body
of the car with intervening rubber or other springs /, preferably both above and
below the yielding arms k.
I prefer also to employ a third spring L, connected at its upper end to the
underside of the car, and at its lower end to the top of the bar J. These springs
are employed to absorb and lessen the shock imparted to the bar J carrying the
contact wheels, from the motion of the car.

page_text: The arms m which carry the contact wheels are electrically connected to the
plates by any suitable mechanical means, but I prefer, in order to insure the
wheels C C being kept in contact with the conductors A, B, to interpose
springs n, Figure 6, which tend to push the wheels outwards in contact with the
conductors A, B, at all times. The plates j j¹ may be provided with binding
posts p, p, to which are connected suitable conductors leading to the motor on
the car.
In order to prevent the jumping of the car from raising the bar J and its contact
wheels C, C¹ so far upwards as to carry them out of contact with the con-
ductors A, B. I affix to the bar J, brackets S, carrying anti-friction rollers s adapted
to come into contact with the underside of the top plates of the conduit when the
bar is raised to any extent, and so keep the wheels C, C₁ in contact with the
conductors A; B.
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
First. The combination of a generator, line conductors and cars having motors
in derived circuits of an electrical railway system, with devices for intermitting the
current in the derived circuits, substantially as set forth.
Second. The combination of a generator, line conductors, and cars carrying
electrical motors, with interrupting contact wheels in connection with said con-
ductors substantially as described.
Third. The combination of a generator, line conductors and cars carrying
electric motors, with wheels to make connection with said conductors, one of said
wheels being an interrupting contact wheel and having a supplementary contact in
a branch circuit to the motor, as specified.
Fourth. The combination of the conduit, carrying electrical conductors, with a
car having a suspended bar carrying contacts for said conductors, and brackets
provided with anti-friction rollers, as and for the purpose, set forth.
Dated this 13th day of October 1885.
J. HENRY JOHNSON,
47, Lincoln's Inn Fields, W.C.,
Agent for the said James Francis McLaughlin.