Improvements in Electric Tramways or Railways.
Year: 1891

page_text: Date of Application, 18th Mar., 1891
Complete Specification Left, 7th Jan., 1592-Accented, 13th Feb., 1892
PROVISIONAL, SPECIFICATION.
Improvements in Electric Tramways or Railways.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this invention (a communication to me
from abroad by Sigmund Schuckert and Co. of Nuremberg, Germany, Manu-
facturers, through their agents Wirth and Co. of Frankfort-on-Main, Germany)
to be as follows:-
My improvements in electric tramways or railways relate to the conductor,
whereby the electric current is conveyed to the motor on the carriage, and consists
essentially in a magneto-electrical method of establishing electrical connection
between a continuous and practically insulated conductor and the particular section,
or sections, of an interrupted conductor with which the contact device upon the
car is, for the time, in electrical connection.
In carrying out my invention, the continuous conductor is laid on the floor of a
sealed tube, preferably of non-magnetic material, and is in the form of a flat strip.
Along the upper side of, and within, the tube is fixed an intermediate sectional
conductor whose lengths correspond to, and are respectively connected by wires
with, the sectional conductor with which the brushes on the car make contact.
The sections of the intermediate conductor are insulated from each other, and from
the main conductor, but are capable of being put in electrical connection therewith,
by a mass of iron filings, or other divided form of that metal, which is caused,
under the influence of magnetic induction exerted by electro-magnets mounted
beneath the car, to bridge over the space between the continuous and the inter-
inediate sectional conductor as the car travels along, thus putting the former
continuously into electrical connection with the sections of the sectional conductor
with which the brushes on the car for the time being make rubbing contact in the
usual manner.
The advantage of this arrangement is that when once the iron particles have
been influenced fresh points of contact form continuously and a small amount of
magnetic force suffices to establish the circuit. The iron particles are preferably
galvanised to prevent oxidation and in order to quickly cause their return to their
normal position of rest after performing their function, the main conductor is
covered with a strip of iron whose remanent magnetism rapidly demagnetizes the
iron particles and by exerting an attractive influence causes them to fail so that
they are not liable to be carried along in the tube. The electro-magnets on the
car are in the circuit of the motor and should the chain of iron particles or pieces
be interrupted from any cause it may be reconstituted by means of a hand magnet
or a small magnetic machine, accumulator or element entirely independent from
the motor.
Dated this 18th day of March 1801
A. ME
LE CLARK,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Tramways or Railways.
I ALEXANDER MELVILLE CLARK of the firm of A. M. & Wm. Clark, of
53 Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this invention (a communication to me
from abroad by Sigmund Schuckert and Co. of Nuremberg Germany, Manu-
facturers, through their agents Wirth and Co. of Frankfort-on-Main Germany)
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :―
My improvements in electric tramways or railways relate to the conductor
whereby the electric current is conveyed to the motor on the carriage, and consists
essentially in a magneto-electrical method and means of establishing travelling
electrical connection between a continuous and practically insulated main conductor
and the particular section, or sections of an interrupted conductor with which the
contact device upon the car is, for the time being, in electrical connection.
Reference being had to the accompanying drawings forming part of this
Specification wherein
Figure 1 is a perspective elevation of the travelling magneto electrical connection
apart from the tube, and car.
Figure 2 shows the car and electro magnets thereon and a cross section of the
line conductors.
Figure 3 is a cross section of the line conductor tube and of the continuous and
intermediate interrupted conductors and their adjuncts therein.
Figure 4 is a longitudinal section and plan of the said conductors showing the
preferred arrangement for preventing the creeping of the magnetizable particles.
In carrying out my invention the continuous conductor is laid on the floor of
a hermetically sealed tube a preferably made of non-magnetic material and laid
below the track between the rails, the conductor being in the form of a flat strip
of copper which would be insulated from the tube if the latter is of conducting
materials. Along the upper side of, and within the tube a, is fixed an intermediate
sectional conductor c whose sections (each of but a few metres in length) correspond
to, and are respectively connected by wires with another external sectional
conductor bedded in asphalte alongside tube a in such position that the brushes
on the car will make contact therewith. The sections of the intermediate sectional
conductor c are insulated from each other and from the tube a and from the main
conductor from which they are distant about 15 millimetres but are put in
electrical connection therewith by a mass, or masses, of iron filings e (or other
divided form of that metal) which is, or are, caused, under the influence of
magnetic induction exerted by electro-magnets mounted beneath the car, to
bridge over the space between the continuous conductor b and the intermediate
sectional conductor as the car travels along, as illustrated in Figure 1, thus
putting the conductor continuously into electrical connection with the sections of
the sectional conductor e and through the connecting wires with the corresponding
sections of the external sectional conductor d with which the brushes on the car
for the time being make rubbing contact in the usual manner whereby the current
is conveyed to the motor on the car. As the car travels along, the metallic
connection of the conductor with the sectional conductor c through the iron
particles travels along also.
The advantage of employing iron particles is that at every passage of the car
fresh points of contact are formed inasmuch as the separate particles continuously
re-arrange themselves and it is practically impossible for them to come into action
again at exactly the same spots; whereas, in the case of a rigid body the same
oints are necessarily repeatedly brought into contact and risk is thus run of their
leing oxydized and causing failure of action.

page_text: A further advantage is that the iron particles owing to their lightness require
but a weak magnetic force to attract them whereas when iron strips were used it
was impossible to directly attract them, special magnetizing rails being required
which are now superfluous. Moreover the distance between the main and sectional
conductor, when finely divided iron is used, may be greater, thus increasing
considerably the safety of working whilst the exciting electro-magnet is much
handier.
Furthermore such strips are difficult to adapt to the curves of the track and the
strains thereby caused have been a source of trouble.
Finally in case of need the iron particles can be easily replaced.
The iron particles are preferably galvanised to prevent oxidation and in order
to cause them to return quickly to their normal position of repose after fulfilling
their function, the main conductor is covered with a strip of iron g whose remanent
magnetism rapidly demagnetises the iron particles and by exerting a counter-
attractive influence causes them to fall so that they are not so liable to be carried
along in the tube.
The path of the motor current is from the generating station through the main
conductor b, the iron particles, to the sectional conductors and d, thence by
brushes to the motor on the car, and the electro magnets freturning by the rails.
The electro-magnets being in the circuit of the motor a hand magnet or small
magnetic machine, accumulator or element entirely independent from the motor
would be provided whereby to reconstitute the chain of iron particles or pieces
should it be interrupted from any cause.
In order to prevent the creeping along of the iron filings and their accumulation
in some parts and denudation in others by magnetic force or mechanical vibration
it is advantageous to divide up the granular metallic mass by insulating material
(such as wood, vulcanized fibre asphalt or the like) applied either in the form of
transverse ribs beneath the conductor e or as a solid mass with (preferably
conical) holes h¹ therein as shown in Figure 4.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is―
1. The herein described method of and means for effecting a travelling electrical
contact between a continuous and sectional conductor for an electric rail or tramway,
which consists in applying a mass or masses of finely divided mobile iron particles
as a medium of electrical connection between the main and sectional conductors,
the said mass or masses being caused to bridge over the gap between said conductors
by the attraction of an electro-magnet on the car so that small magnetic force is
requisite, fresh points of contact will continuously come into action as the particles
re-arrange themselves and the connection will travel along with the car, as
described.
2. In the herein described means of effecting travelling electrical connection,
the combination with the continuous and sectional conductors and the magnetisable
divided mass applied between them as herein specified, of the iron band g applied
beneath the magnetisable divided mass, as and for the purpose specified.
3. In the herein described means of effecting travelling electrical connection, the
dividing up transversely of the magnetisable divided mass into separate masses by
insulating material so as to prevent creeping and heaping up of the magnetisable
particles, as described.
Dated this 7th do- of Tonu 1900
A. MELVILLE CLARK,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.