IMPROVEMENTS IN ELECTRIC RAILWAYS
Year: 1885

page_text: 33
I SYDNEY PITT of Sutton in the County of Surrey Gentleman do hereby
declare the nature of my invention for "IMPROVEMENTS IN ELECTRIC RAILWAYS
(a communication to me from abroad by Leo Daft, a subject of the Queen of
Great Britain and a resident of Greenville New Jersey) to be as follows:-
My invention relates to transmitting power especially for the propulsion of
moving engines upon tracks by electricity and it consists in transmitting the
power over conductors not necessarily highly insulated by means of a current
of electricity of such low tension that the escape from the conductors occasions a
comparatively small loss while at the same time the conductors are not necessarily
protected from accidental contact with animals or human beings which has hereto-
fore in many cases been necessary.
Substantially duplicate machines are used for the generation and reconversion of
the electricity although their resistances are made slightly different. In practice
I use the rails upon which the locomotive engine is to run to carry the electricity
to the motor on the engine.
The generator or generators may be of any well known construction, the
principal requisite being that they shall produce a current of great quantity
or body and of low tension.
I prefer to use a machine the current of which does not exceed 50 volts and the
armature of which has a resistance measure from diametrically opposite sections of
not more than 5 of an ohm.
The motor or motors are similarly constructed and have about the same internal
resistance as the generators.
The generators or generator are connected to the rails and the motor runs upon
the rails receiving current therefrom. The rails do not require any special means
to insulate them other than is materially afforded by the ordinary ties or sleepers.

page_text: I do not herein broadly claim propelling cars having electric motors thereon by
means of currents generated at a station and transmitted to the motors by the rails,
as I am aware that it is not new, but as far as I am aware all attempts to so
operate the motors upon the cars have been by means of comparatively high tension
currents, necessitating peculiar appliances to partially, at least, insulate the rails or
conductors. All such arrangements are expensive to construct, wasteful of the
current and liable to produce injurious effects upon animals or persons coming in
contact with the conductors.

page_text: "
I, SYDNEY PITT of Sutton in the County of Surrey, Gentleman do hereby
declare the nature of my invention for "IMPROVEMENTS IN ELECTRIC RAILWAYS'
which invention has been communicated to me from abroad by Leo Daft, a
subject of the Queen of Great Britain and a resident of Greenville, New Jersey,
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 transmitting power especially for the propulsion of
moving engines upon tracks by electricity and it consists in transmitting the
power over conductors not necessarily highly insulated by means of a current of
electricity of such low tension that the escape from the conductors occasions a
comparatively small loss while at the same time the conductors are not necessarily
protected from accidental contact with animals or human beings which has hereto-
fore in many cases been necessary. In practice in order to supply the electricity to
the conductors I prefer to utilize a machine which generates an electric current
having a tension not greater than thirty volts, although this tension may be
exceeded without departing from the principle of my invention. Substantially
duplicate machines are used for the generation and reconversion of the electricity,
although their resistances are made slightly different. In practice I use the rails
upon which the locomotive engine is to run to carry the electricity to the motor on
the engine. My invention will be readily understood from the accompanying
drawings which show a general view of the arrangement of the generator and
motor in which A is the generator; B, the connections from the generator to the
conductors or rails L, and A¹, the motor on the car C, which runs upon the
conductors L.
The generator or generators may be of any well known construction, the
principal requisite being that they shall produce a current of great quantity or
body and of low tension. I have shown a generator of a well known type, having
the field coils and the armature wound with large conductors of low resistance.
I prefer, however, to use a specific machine which I have invented but which
forms the subject matter of a separate application and is not described herein.
I prefer to use a machine the current of which does not exceed 50 volts and the
armature of which has a resistance measured from diametrically opposite sections
of not more than, 5 of an ohm.
The motor or motors are similarly constructed and have about the same internal
resistance as the generators.
In the drawing I have shown the generators or generator as connected to the
rails and the motor runs upon the rails receiving current therefrom. The rails do
not require any special means to insulate them other than is materially afforded
by the ordinary ties or sleepers. I have not deemed it necessary to describe
specifically the details of construction and connections of the machine as those are
well understood by persons skilled in the art.
I do not herein broadly claim propelling cars having electric motors thereon by
means of currents generated at a station and transmitted to the motors by the

page_text: rails, as I am aware that it is not new, but as far as I am aware all attempts to so
operate the motors upon the cars have been by means of comparatively high
tension currents, necessitating peculiar appliances to partially, at least, insulate the
rails or conductors. All such arrangements are expensive to construct, wasteful of
the current and liable to produce injurious effects upon animals or persons coming
in contact with the conductors.
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
The combination in an electric railway system of a stationary dynamo adapted
to generate currents of low tension, conducting rails for such currents, practically
non insulated and cars provided with electric motor constructed to make electrical
contact with said conductors and to be operated under currents of low tension.
Dated this 21st day of April 1885.
CARPMAEL & Co.,
Agents for the Applicant.