Improvements in Electric-railway Systems.
Year: 1891

page_text: Date of Application (in United Kingdom), 7th Jan., 1891
Complete Specification Left, 7th Jan., 1891-Accepted, 25th Apr., 1891
COMPLETE SPECIFICATION.
Improvements in Electric-railway Systems.
I, CHARLES K. HARDING, of Atlantic, in the County of Cass, and State of Iowa,.
United States of America, Electrician, do hereby declare the nature of this inven-
tion, and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This invention relates to an improvement in electric railway systems of that class
which embraces a central generating plant, electric motors upon the vehicles to be
propelled, and conductors through which the current generated is conveyed to the
several motors; and one of the principal objects of my invention is to provide an
improved construction in means for distributing the electric current from a dynamo
or generator to a series of electric motors upon vehicles or trains, by which the
employment of overhead or other exposed supply conductors carrying the current
from the generator to the motors may be dispensed with, thereby insuring entire
safety from accidents liable to occur wherever exposed conductors are employed.
My invention has reference more especially to that means of distribution known
as the "multiple arc system, or that in which the translating devices employed
for converting electric into mechanical energy are located in parallel or branch
circuits, derived from a main conductor which is supplied from the generator, and
in which part of the circuit may be, if desired, formed by the ground instead of by
a return wire, such system being heretofore employed in electric street railways,
wherein the current from the generator after passing through the motor, commonly
passes through the wheels of the vehicle to the track rails, and from thence to the
ground.
My invention embraces as one of its principal features an insulated continuous
main or supply conductor, a series of exposed separate insulated conductor-sections
arranged paralled with the continuous or supply conductor, travelling contact
devices on the vehicle for taking the motor current from the said sections and
electro-magnetic contact-devices for bringing the said conductor sections separately
into electric connection with the continuous or supply conductor, such contact
devices being operated by an exciting-current derived from the main conductor
through a second travelling contact device on the vehicle, whereby each of said
sections is brought into connection with the supply only when a vehicle is passing
the same.
By this construction I am enabled to locate the insulated conductor-
sections in any position in which they may be most conveniently placed for exposure
to the travelling contact device of the motors, because there is no current in said
sections except when the travelling contact devices are passing over the same, while
at the same time the main or supply conductor may be completely insulated and
placed in any position most suitable for its protection from mechanical or other
injury.
My invention also embraces a conduit or inclosure surrounding and insulating the
supply conductor by which the current is conveyed from the generator or source of
supply to the motors on the vehicles, said conduit being entirely closed so as to

page_text: prevent the possibility of access of water or moisture to the conductor, together
with a series of insulated conductor sections sustained in the conduit with their outer
edges exposed in such manner that they may be acted upon by the travelling contact
devices of the vehicle, and means for bringing said insulated sections separately
and successively into electric connection with the supply-conductor, such conduit
being adapted to be placed in the ground between the track rails or elsewhere along
the rails in such manner as to allow the contact devices of the vehicle to move upon
or in contact with the insulated conductor-sections.
The invention may be more readily understood by reference to the accom-
panying drawings, which shew one practical form of apparatus embodying my
invention.
In said drawings:
Fig. 1, is a diagram illustrating the construction of the electric devices forming
part of my invention;
Fig. 2, is a central longitudinal vertical section of a conduit for a railway, together
with a
car, shewing the several operative parts within and adjacent to the
Fig. 3, is a cross section through the conduit and track rails taken upon the
line 3-3 of Fig. 2;
same;
Fig. 4 is an enlarged detail cross-section of the conduit, taken on the line 4-4 of
Fig. 6;
Fig. 5 is an enlarged detail cross-section shewing one of the conduit-sections in
end view;
Fig. 6, is an enlarged detail view in longitudinal vertical section of the
adjacent ends of two conduit-sections, together with the parts adjacent thereto;
and,
Fig. 7 is a detail cross section taken upon the line 7-7 of Fig. 6.
As illustrated in said drawings, A. is the insulated main or supply conductor of
the system, which is connected at one end with the dynamo or electric generator at
the central station or plant, and which extends through the length of the road on
which the cars are to be operated. Said conductor is located within a conduit,
herein shewn, Fig. 3, as located between and parallel with the track rails, B, B, said
conduit being indicated in the drawings as a whole by C.
D, D, D, are a series of separate insulated conductor sections arranged end to
end parallel with the supply conductor A, with insulating material between them,
as indicated at D2, D2, and sustained in the upper part of the conduit C, in such
manner that the upper edges of said conductor-sections are exposed to allow contact
therewith of the travelling contact devices upon the car or vehicles.
Said con-
ductor sections may be made of any suitable metal, as iron, copper, or phosphor-
bronze, or of a combination of metals.
E represents the car or vehicle having wheels E' E', which rest on the track
rails, B, B, and carrying brushes or travelling contact devices F and G, which
travel in contact with the conductor-sections D, D. The contact device F, as
herein shewn consists of rollers f, f, mounted on a horizontal bar f', which is attached
to a non-rotating stem f³, having sliding bearing in a depending insulated arm,
which is rigidly attached to the car, separate brushes, being also preferably
attached to the bar and bearing on the conductor-section to afford a greater area
of contact with the latter. The travelling contact device, G similarly consists of
two anti-friction wheels or rollers g g, mounted on a longitudinal bar g', having a
vertical stem 2, which is guided in a depending insulated arm 93, attached to the
car and provided with brushes 9', attached to said bar and acting on the conductor
section. The bars f, glare adapted to play freely in a vertical direction by the
sliding of the stems f2, 92, in the arms f³, 9, thereby allowing the anti-friction
rollers f, f, g, g, to remain in contact with the insulated conductor sections, not-
withstanding irregularities in the same or in the track rails. As herein shown the
contact devices act by gravity; but if found necessary or desirable, springs may be
employed to hold them against the conductor sections.

page_text: H indicates an electric motor, the shaft of which is connected by means of gear
wheels h, h with the axle, e of the wheels E' E'.
I indicate one of the rheostats which are commonly placed at opposite ends of
the car for controlling the current passing through the car-motor, and I' a
conductor on the car leading from the arm f³ to said rheostat I; I2 a conductor
leading to the rheostat at the opposite end of the car, which is not shown in the
drawings, and 13 a conductor leading from the rheostat last mentioned to the
motor H.
J is a rheostat or resistance box, and J¹ is a conductor leading therefrom to
the arm of the contact device G, and J2 is a conductor leading from said
rheostat to the wheel axle e', by which electric connection is made with the
track-rails.
It is of course understood that the opposite electrode or terminal of the motor
is connected with the ground through the medium of a conductor leading therefrom
to the axle in the usual manner.
The current for operating the electric motor is transmitted from the insulated
main conductor A to the insulated conductor-sections D, D, D by contact devices
constructed as more clearly shewn in the diagram Fig. I and each of which is made
as follows: Attached to each section D is a bar or rod D' in electric connection
with said section, and forming a conductor through which the current is transmitted
to said section. K is an arm or standard which is in electric connection with the
said conductor A, and is arranged adjacent to the arm or bar D'. L is an electro-
magnet supported on the arm K, and L' is an armature pivoted to said arm K and
arranged opposite the pole piece of the magnet L. Said armature L' is adapted
for contact with the bar D', when drawn by the magnet toward the latter, but is
arranged to fall away from the said bar D', either by gravity, or by a suitable
spring, at times when the electro-magnet is inert, or when no current is passing
through the coils of the same. In the particular construction illustrated said
armature L', is arranged horizontally with its free end beneath the said bar D',
so that it tends to fall by gravity away from the latter. The magnet shewn has
only a single coil, so that the armature forms in effect part of the magnetic circuit
of the magnet.
It follows from the construction described that when said
armature L, is drawn into contact with the bar D', by the passage of an electric
current through the coils of the electro-magnet L, an electric connection between
the main or supply conductor A, and the insulated section D will be established
through the bracket K, the armature L', and the bar D'. One terminal of the
magnet coil of each of the electro-magnets L is connected with a conductor l, with
a conductor section adjacent to that to which the electro-magnet belongs, as, for
instance, in the diagram, Fig. 1 the several conductor sections, D, D, D, are
numbered for convenience 1, 2 and 3, and in said Fig. 1 the conductor extends
from the electro-magnet of conductor section No. 1 to and is connected with the
bar D of conductor section No. 2, while the conductor belonging to the conductor
section No. 2, extends to and is connected with the bar D' of section No. 3. The
other end of the coil of each magnet is connected with a conductor to which is
connected two branch conductors 12, 13. The branch conductor 3 leads to an
insulated contact point M, which is located adjacent to the electro-magnet, and in
position for contact with an arm L2 of the armature L', the parts being so arranged
that the part L2 will be in contact with the contact piece M at the same time
that the armature itself is in contact with the bar D¹. The other branch
conductor leads to the contact device belonging to the adjacent conductor section
remote from that to which the conductor 12 is connected. In other words, said
conductor leads to the section at one end of the section to which the magnet
belongs, while the conductor 12 leads to the contact devices belonging to the con-
ductor sections at the opposite end of said section to which the electro-magnet
belongs. The terminal of said branch conductor is attached to a contact piece N
which is arranged for contact with the arm L2 of the armature L¹ in the same
manner as the contact piece M, the parts being so arranged that the said arm L² is

page_text: brought in contact with both of the contact pieces M and N when the armature is
acted upon by the electro-magnet and is released or freed from contact with said
contact pieces when said armature is free from the influence of the electro-magnet,
and has fallen away from or is out of contact with the bar D¹.
In the operation of the parts of the apparatus above described the current which
actuates the motor on the car or vehicle is derived from the main conductor A, and
passes from said conductor through one of the insulated conductor sections D to the
travelling contact device F of the vehicle, connection being afforded between said
section D and the main conductor through the medium of the bracket K,
armature L', and the bar D', when by the passage of a current through the coils
of the electro-magnet L, the armature L', is held against the bar D'. The
travelling contact device G is arranged at a distance from the travelling contact
device equal to the length of the conductor sections D, so that when said
travelling contact device F which carries the current to the motor, is engaged with
one conductor section, the travelling contact G will be engaged with the adjacent
conductor section in advance of it, the construction being such that said travelling
contact device forms with the conductor section with which it is in contact and with
the coils of the electro-magnet belonging to the insulated section at the rear of the
one upon which the said contact device G is resting, a circuit carrying a branch
electric current derived from the main conductor, the said magnet coils and
travelling contact device G thus being in parallel, or in multiple arc, with the
motor, and the quantity of such branch current is being determined by the rheostat
or resistance box J. In other words, the electro-magnet contact device by which
each conductor section is brought into connection with the continuous main
conductor, is held in position for maintaining such connection during the time the
travelling contact device F is passing along or over each conductor section by
means of a branch electric current established through the travelling contact
device G and the next adjacent conductor section in advance of it.
It will of course be understood that the quantity of current required to operate
the electro-magnetic device is relatively small and that sufficient resistance will be
introduced in the circuit by the resistance box J to prevent the passage of more
than the necessary quantity of current.
The branch conductor 2 is for the purpose of establishing a current through each
electro-magnet L as soon as the travelling contact device G reaches the conductor-
section next in advance of that to which the electro-magnet belongs, in order to
draw the armature against the bar D', and thereby establish electric connection
between the said conductor section D and the supply-conductor A. This may be
more readily understood by reference to Figures 1 and 2. Supposing the travelling
contact device F of the motor-circuit has just passed from the conductor section
No. 1 to the conductor section No. 2, the travelling contact device G will at the
same time travel from the conductor section No. 2 to conductor-section No 3.
When the travelling contact device G is still on conductor-section No. 2, the
armatures L' of Nos. 2 and 3 will be free from the bars D₁; but as soon as the said
travelling contact device passes from the conductor-section No. 2 to conductor-
section No. 3, a circuit will be completed through the magnet coils of No. 2, said
circuit being derived from conductor A. through the branch conductor, 12 and the
contact devices of No. 1. At this time a closed circuit may be traced from the
conductor A through the bracket K, the arm L2, and contact-piece N of section
No. 1, through the branch conductor 2 to the bar D', and conductor section No. 3.
As soon, however, as the circuit is completed through the magnet coils of
section No. 2, the armature will be drawn into contact with the bar D¹, thereby
making connection between the conductor-section No. 2 and the conductor A. At
the same time, however, the arm L² of the armature will be brought against the
contact-pieces M and N of said section No. 2, thereby establishing a circuit from
the said conductor A through the bracket K, the arm L², the contact piece M, the
branch conductor 3, the conductor and the magnet coils of section No. 2, and
also through the conductor and section No. 3. After the circuit has been

page_text: completed as last described the current will cease to pass through the conductor 12
from the fact that it will have a shorter and more direct path with less resistance
through the parts last referred to, and the armature will be maintained in contact
with the bar D' during the passage of the travelling contact device over the said
section No. 2 by means of the current passing through said parts last referred to.
As soon as the contact device F has passed from section No. 1 and the contact
device G has passed from section No. 2 to sections Nos. 2 and 3 respectively, the
circuit through the magnet coils of section No. 1 will be broken and the armature
belonging to the latter will fall away from the bar D', thus breaking the connection
between the said section D No. 1, and the conductor A. and leaving said section No. 1
completely insulated.
In order to prevent interruption of the current supplying the motor in the passage
of the travelling contact device F from one conductor-section to another, said
travelling contact device is so constructed as to overlap the insulated space between
the ends of the adjacent conductor-sections, and for this purpose the contact device F
is herein shown as provided with two anti-friction rollers f,f hereinbefore described
it being obvious that one of said anti-friction wheels or rollers will rest in contact
with one conductor-section, while the other wheel or roller is still in contact with
the other section. The contact device G, being similarly constructed, the branch
circuit by which the electro magnetic contact device is actuated will be maintained
through the electro-magnet belonging to contact device of one section-as, for
instance section No. 1-until the rearmost anti-friction wheelf has passed clear of
section No. 1. It follows that for a short time during the passage of the travelling
contact device from one section to another, both of the two adjacent conductor-
sections will be in circuit, or, in other words, that the current supplying the motor
will pass in part through one conductor-section and in part through the other
conductor-section at such time.
the same.
The conduit C embraces important features of novelty, and in the form thereof
which I have for convenience herein illustrated is made up of separate lengths or
sections, each of which is of the same length as one of the conductor-sections and
contains in one end the electro-magnetic contact devices hereinbefore described,
said conduit being provided for this purpose with a recess or chamber to contain
Each section of the conduit consists of a casing O, made hollow or
tubular in its lower part, and having in its upper part a longitudinal recess or
channel within which is placed the conductor section, and the insulating material
which surrounds and supports the same. In the particular construction of the
conduit herein illustrated, the same is made with two parallel side walls o o, a hori-
zontal bottom plate o', which preferably extends outwardly beyond the side walls
in the form of flanges so as to give a firm bearing or support for the conduit when
the latter is sustained on the cross-ties in the manner shown, Fig. 3, and a horizontal
diaphragm o², arranged above and parallel with the horizontal bottom plate, forming a
closed passage within which the main conductor A and the conductors and are
located. At their upper margins the said walls are preferably provided with
outwardly and upwardly extending flanges o³, o³, affording a wide space at the top.
of the conduit for the insertion of insulating or filling material at opposite sides of
the conductor section.
In connection with a conduit constructed in the particular form described, I employ
a support P of insulating material which is fitted between the upper vertical parts
of the side walls o o of the conduit and rests upon the diaphragm o² thereof, and is
notched or grooved in its upper surface to receive the conductor section which, in the
instance illustrated, is formed of a flat bar arranged with its flat sides vertical.
The insulating support P, when thus made, will be constructed of wood, porcelain,
or other material of sufficient hardness, strength and rigidity to support the
conductor section in position, and to withstand any strains shocks or blows to which
the said section may be subjected. If made of wood, the support P may extend
continuously the entire length of the conduit section; but if made of porcelain or
or other similar material it will commonly consist of short pieces or blocks, which

page_text: may be set in contact with each other or at some distance apart, as may be found
necessary or desirable. Said support P will be secured to the conduit, and to the
conductor section by any suitable fastening devices, those herein shown consisting of
bolts or rivets p, inserted through the opposite side walls of the conduit and the lower
part of the support P, and the similar bolts or rivets p¹ inserted through the upper
part of the said support P and through the conductor section.
The support P preferably terminates considerably below the upper edge or
surface of the conductor section, and the space at either side of the conductor
section, and between the latter and the flange o³ of the conduit is filled with
masses of insulating material, applied, preferably, in a plastic condition, the
inner surfaces of the said flanges being provided with projections, roughened, or
otherwise constructed to retain said masses QQ in place. A desirable construction
of the parts is herein shown, in which the flanges o³, o³, are provided at their upper
edges with inwardly extending ribs o, of which serve to hold the said insulating
fillings QQ, in place, while at the same time affording a thick or strong margin at
the upper edges of the side wails of the conduit to give suitable strength to the
same and to partially protect the fillings Q, Q, it being intended that the upper
edges of the conduit shall be set flush with the surface of the street-roadway, so
that considerable strength is required therein to withstand the wear and rough usage
to which they may be subjected. The upper edge of the conductor-section is
preferably placed considerably above the side margins of the conduit, and the
filling Q, Q, sloped or inclined from the conductor section outwardly to the side
margins of the conduit. This construction brings the exposed part of the conductor
section above the level of the roadway adjacent to it, so that the water will tend to
flow away from the conductor section, and the prompt drying of the latter will be
facilitated. The elevation of the upper edge of the conductor section above the
edges of the conduit in the manner described also enables the conductor section to
be worn away to a considerable extent without bringing it too low with reference to
the sides of the conduit, it being obvious that if the conductor section was originally
set level with the sides of the conduit, any wearing away of the same would form a
depression in which water might accumulate.
The conductors within the tubular part of the conduit may be insulated in any
manner found convenient or desirable, but preferably they are imbedded in a mass Q¹
of insulating material which fills the entire space within the conduit, and thereby
insures the exclusion of moisture, gases and other substances which might act
injuriously upon the wires, or upon the insulation immediately surrounding the
same, it being intended even when said insulating filling is used to employ conductors
provided with the usual wrapped or braided fibrous or other insulating coating.
The employment of such additional insulating filling is highly desirable in an electric
system of the kind described herein for the reason that the additional insulation
thus obtained renders safe the carrying of the additional voltage, which is rendered
possible by the system of supplying the motors herein described.
The several conduit sections constructed as described are attached to each other by
joints made water and air tight, and which are at the same time adapted for allowing
expansion and contraction of the metal forming the conduits. As herein shown the
sections are provided at their ends with flanges O', O', Figs. 5 and 7, through which
are inserted bolts to hold the sections together, a packing ring o of elastic or
compressible material being inserted between the flanges to make tight joints, and
to provide for the expansion and contraction of the sections, said ring o' being
arranged to extend between the abutting ends of the diaphragms o², Fig. 6 so that
the access of air or moisture to the lower or tubular part of the conduit is effectually
prevented. At one end of each conduit-section is formed an enlargement or
chamber 02, Figs. 6 and 7, within which is placed the several parts constituting the
contact device. To form such chamber the diaphragm o² is elevated to give suitable
depth to the same, and the side walls o o are spread apart to give suitable width.
To afford access to the interior of the chamber 02 an opening is made in one side
of the same, such opening being provided with a cover O', (herein shown Fig. 7, as

page_text: being held in guide-grooves, and adapted to slide into place from above). The
joints around said cover are packed or luted with some plastic material to exclude
air and moisture.
The several operative parts of the contact device are herein shown as constructed
and arranged within the chamber 02 as follows:
R is a plate or slab of wood, or other insulating material placed in the bottom of
the chamber, and which supports one end of that part or section of the conductor A
which is within the conduit section. The bracket K which sustains the electro
magnet is herein shown as resting upon and rigidly attached to the end portion of
the conductor, which is sustained upon the plate or slab R, said bracket being free
from contact with the iron casing so that it is entirely insulated from the same.
S is a support composed of insulating material which sustains the contact pieces M
and N, the latter being herein shown as having the form of screws inserted through
the support S, thereby enabling said contact pieces to be bodily adjusted with
reference to the arm L of the armature. Said arm L in this construction consists
of two separate flexible arms or prongs 14, 1³ adapted to separately engage the
contact pieces M and N, so that perfect contact will be made by both of the said
contact pieces, without reference to the adjustment of the armature to which said
prongs,, are attached. The bar D in this construction passes downward through
the insulating support 1', through an opening in the diaphragm o², into the chamber (*,
the bar being suitably insulated from the diaphragm, where it passes through the
same as shown.
The end of the tubular part of the conduit section adjacent to the joint between
the conduit section is preferably closed by a plate or slab s¹, of wood or other
insulating material to form an end wall against which the filling Q will come in
inserting the same. The conductors 1 and 2 are extended through the slabs s¹, and
their ends project beyond the same so as to enter the chamber 02, when the
sections are placed together, said conductors being joined within the chamber to
the parts with which they are connected by soldering or in any other convenient
The conductor A also projects through the slab S' and the adjacent ends
of the parts of the said conductor may be united by any suitable form of joint, that
herein shown consisting of a sleeve a fitting over same within the chamber 02, and
secured by solder or otherwise.
manner.
It will of course be understood that the particular arrangement illustrated of the
parts of the contact device within the chamber is only one of the many which may
be employed without departing from the spirit of my invention.
In laying the conduit as hereinbefore described the filling QQ over the joints
between the sections will not be inserted until after the conduit sections have been
put in place and bolted together, it being the intention that such filling should be
applied in plastic state, so as to extend continuously from one conduit section to
another, thereby aiding in excluding water from the joints between the conduit
sections. The insulation between the adjacent ends of the sections will preferably
consist of plates D2 D2 of hard and strong insulating material such as vulcanized
fibre or hard rubber. In order that said plates may be strongly and securely held
in place they will preferably be arranged to extend outwardly between the ends of
the insulating supports PP, with their lower edges in contact with the diaphragm oʻ
in the manner clearly shown in Fig. 6.
The means herein described for transmitting the current from a central station to
the electric motors on vehicles has the advantage of affording perfect safety to
persons and animals, even though the same may come in direct contact with the
exposed conductor sections, through which the current is transmitted to the
travelling contact devices or brushes of the vehicle it being obvious from what has
been before stated that in no case can any one of said conductor sections be brought
into electric connection with the main line or supply conductor, which is connected
with the source of electric supply, except when the travelling contact devices of the
vehicle are passing over the conductor section. It is obvious, furthermore, that
the said conductor sections can only be brought progressively or successively into

page_text: electric connection with the main or supply conductor. This will be understood
from the fact that the branch circuit can only be established through the second or
auxiliary travelling contact device G when the same is resting on one conductor
section, and a conductor section at the rear of it is in electric connection with the
main or supply conductor for the reason that such branch circuit by which the
electro-magnetic contact device is operated can only be established through
the magnet coils when the contact devices of such section at the rear of the one on
which the contact device G is moving is closed. If, therefore, both of the brushes
or travelling contact devices of the vehicle are removed from contact with the
conductor sections, the electric circuits between the exposed conductor sections and
the supply conductor cannot be re-established except by closing one of the contact
devices by mechanical means especially applied for the purpose, and in practice
this may be done in case of an accident, such as the derailment of the car, by opening
one of the chambers of the conduit and moving the armature of the contact device
by hand, or bringing forward from the supply station another similar vehicle.
A magnet may be employed to move the armature so as to close the circuit,
in which case the electric connection may be re-established without opening the
conduit.
The employment of the circuit controlling device in the branch circuits (formed
in the particular construction herein illustrated by means of conductors 12, 13) is
obviously necessary in order to maintain said circuits normally open and thereby
prevent the passage of any current from the supply-conductor through the coils of
the electro-magnets to the conductor sections, or from one to another of the
conductor-sections, it being obvious that inasmuch as one terminal of each of said
coils is connected with one conductor section, the other terminal must be temporarily
connected with the main or supply conductor in order to derive the branch current
through the electro-magnet coils, and if such connection were permanent a path for
the current would be afforded from the supply conductor to each conductor section.
By the employment of circuit controlling devices in said branch circuits, however,
which circuit controlling devices are controlled by the movement of the armatures
belonging to the contact devices, said circuits are closed only when the main contact
devices are closed and are open at all other times, so that the conductor sections
are completely insulated, except when the vehicle is passing over or along the
same, at which times the conductor sections are covered or protected by the body
of the vehicle or vehicles. As far as the breaking of said branch circuits at the
proper time is concerned, it is not necessary that the circuit controlling devices
should consist of contact pieces which are acted upon directly by a part or arm
attached to the armature of each contact device in the manner illustrated; but said
circuit controlling devices for the branch circuits may be controlled or operated by
or from said main contact devices or the armatures thereof by other devices either
electric or mechanical in their character as, for instance, the conductor 12 which
forms part of the branch circuit by which the electro-magnet is excited to close the
main contact device is shown in the drawing as extending from each contact device
to the one at the rear of it, referring to the direction of movement of the car, and
said conductor 12 is shown as connected with the main or supply conductor by means
of a circuit controlling device located adjacent to the contact device last referred to.
This construction, however is not essential, and the said conductor 12 may be
connected with the main or supply conductor at any point, and through a circuit
controlling device elsewhere located, provided said circuit controlling device is
operated from, by, or in unison with the said contact device last referred to by
suitable electrical or mechanical connections, it only being necessary that the circuit
controlling device should be closed to complete a circuit through the conductor
when the said contact device is closed, and should be opened to break the circuit
through said conductor when said contact device is opened.
By reason of the complete insulation of the exposed conductor sections made
possible or obtained by the construction herein illustrated a current of much higher
voltage may be employed in an electric railway system embodying such features of

page_text: construction that have been heretofore safe or practical in electric railways it being
obvious that the main or supply conductor of my apparatus may be insulated in the
most perfect manner to carry safely currents of the highest tension, while in no case
is such conductor brought into electrical connection with any object except through
the conductor sections and the brushes or travelling contact devices of the vehicle
when protected by the latter. It is to be especially noted in this connection that there
is little or no danger of the escape of the current from the conductor sections by
reason of defective insulation, it being a matter well understood in the art that
small or short sections of conducting material are less liable to leakage than greater
lengths of the same kind of conducting material even when provided with insulation
of the same kind and character.
By the employment of the electro magnetic contact devices herein shown in
connection with the secondary or auxiliary brushes or travelling contact devices all
of which are arranged in parallel or multiple are with the motor circuit, I am
enabled to operate said contact devices by the use of a very small proportion of
the entire current supplied for the operation of the electric railway system while
at the same time enabling the electro-magnet coils and other parts to be made of
small size and economical in construction. A system thus constructed therefore
has the advantages of being more economical, both as in the consumption of
current and in the cost of the plant and the maintenance thereof, as compared with
a similar system in which the electro magnet coils of the contact devices are
placed in a series with the motor on the car. The construction last referred to,
however, is a practical one, although, so far as I am now aware, not so advantageous
as that herein specifically illustrated and described; but inasmuch as it is, as far as
I know, a novel one, and affords a means of carrying out the general or broad
features of my invention, the same is intended to be covered by the broad claims
hereto appended.
The location of the main or supply conductor within an inclosure or conduit
which is embedded in the ground, and is parallel with the return conductors formed
by the track rails and the earth, has the important advantage of preventing
inductive interference with telephone, or other wires which may be located adjacent
thereto, and in this respect the conduit system herein described has the same
advantages as the so-called "double trolley system of distribution for electric
railways which has heretofore been devised for this same purpose.
""
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1. An electric railway comprising an insulated continuous main or supply
conductor, a series of separate exposed insulated conductor-sections, an electric
motor on the vehicle to be driven, a travelling-contact device in circuit with the
motor moving in contact with said conductor-section, electro-magnetic contact
devices constructed to bring said conductor-section separately into electric
connection with the main or supply conductor, normally open branch circuits in
multiple are with the motor for operating said contact devices, and means for
closing said branch circuits, comprising a conductor upon the vehicle through
which said branch circuits are successively closed in the passage of the vehicle,
substantially as described.
2. An electric railway system comprising an insulated continuous main or supply
conductor, a series of separate exposed insulated conductor-sections, an electric
motor on the vehicle to be driven, a travelling contact device upon the vehicle in
contact with the conductor-sections and forming part of the motor-circuit,
electro-magnetic contact devices constructed to bring said conductor sections
separately into electric connection with the main or supply conductor and normally
open branch circuits in multiple arc with the motor for operating said contact
devices said branch circuits embracing said conductor-sections a conductor on the
B

page_text: vehicle, and a second travelling contact device on the vehicle moving in contact
with the conductor-section substantially as described.
3. An electric railway-system comprising an insulated continuous main or supply
conductor a series of separate exposed insulated conductor-sections, an electric
motor on the vehicle to be driven, a travelling contact device in circuit with the
motor moving in contact with said conductor-sections, electro-magnetic contact
devices constructed to bring said conductor-sections separately into electric
connection with the main or supply conductor, and normally open branch circuits
in multiple arc with the motor for operating said contact devices, said branch
circuits embracing said conductor sections, a conductor on the vehicle, and a second
travelling contact device on the vehicle, also moving in contact with the conductor-
sections, but arranged to rest in contact with the conductor-sections other than
those upon which rest the first or motor contact device, substantially as described.
4. An electric railway system comprising an insulated continuous main or supply
conductor, a series of separate exposed insulated conductor-sections, an electric
motor on the vehicle to be driven, a travelling contact device upon the vehicle in
contact with the conductor sections and forming a part of the motor-circuit, electro
magnetic contact devices constructed to bring said conductor-sections separately
into electric connection with the main supply conductor, and branch circuits in
multiple arc with the motor embracing conductors connecting the magnet coils of
the electro magnetic contact devices of the several conductor-sections with adjacent
conductor-sections, and a second travelling contact device on the vehicle arranged
to move in contact with conductor sections other than those upon which the first or
motor contact devices rest, substantially as described.
5. An electric railway system comprising an insulated continuous main or supply
conductor, a return conductor, a series of separate exposed insulated conductor-
sections, an electromotor on the vehicle to be driven in circuit with said conductor
sections and with the return conductor, a travelling contact device upon the vehicle
in contact with the said conductor sections and forming part of the motor circuit,
electro-magnetic contact devices constructed to bring said conductor sections
separately into electric connection with the main or supply conductor, and branch
circuits in multiple are with the motor, said branch circuits embracing conductors
connecting the magnet-coils of the electro magnetic contact devices of the several
conductor sections, a second travelling contact device on the vehicle arranged to
move in contact with conductor-sections other than those upon which the first or
motor contact device rests, and a conductor on the vehicle in electric connection
with the said return conductor, substantially as described.
6. The combination with an insulated continuous main or supply conductor, of a
series of separate exposed insulated conductor sections, electro magnetic contact
devices for each conductor section adapted to bring the same separately into
electric connection with the continuous or supply conductor, conductors connecting
the electro-magnet of each contact device with the next adjacent conductor section
at one side of the same, other conductors leading from the opposite terminals of
the electro-magnet coils of the several contact devices, each of said conductors
being branched to form two circuits both of which are connected with the main or
supply conductor, one of said circuits being provided with a circuit controlling
device controlled by the contact device of which said electro magnet forms a part
and the other circuit being provided with a circuit controlling device controlled by
the contact devices belonging to the next adjacent conductor section at the opposite
side of said contact device last mentioned, substantially as described.
7. An electric railway system comprising an insulated continuous main or supply
conductor, a series of separate exposed insulated conductor sections, an electric
motor on the vehicle to be driven, travelling contact devices on the vehicle, electro-
magnetic contact devices for bringing said conductor sections separately into
electric connection with the continuous or supply conductor, a conductor connecting
the magnetic coils of the electro magnet of the contact device cf each conductor

page_text: section with the next adjacent conductor section, a second travelling contact
device on the vehicle arranged to move in contact with the conductor sections
adjacent to those upon which the contact devices of the motor circuit are resting,
whereby branch circuits parallel with the motor circuits are completed through
said magnet coils, and a resistance device upon the vehicle in circuit with said
magnet coils and conductor sections, substantially as described.
8. The combination with an insulated continuous main or supply conductor and
a series of exposed separate insulated conductor sections, of an electro magnetic
contact device for bringing each section separately into electric connection with the
main or supply conductor, said contact device consisting of an arm
or bar in
electric connection with the conductor section, an electro magnet and a movable
armature operating to close the connection between the said arm or bar and the
main conductor when a current is passing through the electro magnet coils, a
conductor leading from one terminal of said electro magnet coil to the next
adjacent conductor section at one side of said contact device, and a conductor
leading from the opposite terminal of the electro magnet coil and branched to form
two circuits each of which includes a circuit controlling device, one of said circuit
controlling devices being actuated by the armature of the said contact device and
the other circuit-controlling device being actuated by the armature of the contact
device belonging to the next adjacent conductor section at the opposite side of said
contact device, substantially as described.
9. The combination with a continuous insulated main conductor, of a series of
insulated exposed conductor sections, blocks of insulated material placed between
the ends of the sections and forming a continuous bearing surface, and a conduit
surrounding or inclosing the said continuous main conductor and embracing a con-
tinuous body of insulating material by which the said conductor-sections and
insulating blocks are supported, substantially as described.
10. The combination, with a continuous insulated main conductor, of a series of
insulated exposed conductor sections, blocks of insulated material interposed
between the ends of said sections, contact-making devices for bringing the said
insulated sections separately into circuit with the main conductor, and a conduit
surrounding or inclosing the said continuous main conductor and contact devices,
said conduits embracing a continuous body of insulating material in which the said
conductor sections are imbedded with one of their side edges exposed, substantially
as described.
11. The combination with a continuous insulated main conductor, of a series of
exposed insulated conductor sections and a conduit surrounding or inclosing the
said continuous conductor and provided at one side with a mass or body of
insulating material in which the said insulating sections are imbedded and by
which they are supported with one of their sides or edges exposed, substantially
as described.
12. The combination with a continuous insulated main conductor, of a series of
insulated conductor-sections, contact devices for bringing the said insulated
sections separately into circuit with the main conductor, and a conduit surrounding
or inclosing the said continuous conductor and the contact devices and embracing
an external mass or body of insulating material, by which said conductor-sections
are supported and having inclosed recesses or chambers to contain the said contact
devices, substantially as described.
13. The combination with a continuous insulated main conductor, of a series of
insulated conductor-sections, contact-making devices for bringing the conductor-
sections separately into connection with the main conductor, a conduit consisting
of a closed tubular lower part in which are located said conductors and contact
devices and having in its upper part a groove or channel within which the con-
ductor sections are located, and a mass or body of insulating material located in
said groove or channel and sustaining said conductor sections, substantially as
described.

page_text: 14. The combination with a continuous insulated main conductor, of a series of
insulated conductor-sections, contact making devices for bringing the conductor
sections separately into connection with the main conductor, a conduit consisting
of a tubular lower part in which are located said conductors and contact devices
and having in its upper part a groove or channel within which the conductor
sections are located, supports of hard or rigid insulating material resting on the
bottom of the groove or channel and engaging the lower parts of the conductor
sections, and a mass of waterproof insulating material filling the said channel at
either side of the conductor sections, substantially as described.
15. The combination with a continuous insulated main conductor and a series of
separate insulated conductor sections, and contact devices for bringing the insulated
sections into electric connection with the main conductor, of a conduit consisting
of a series of conduit sections, each conduit section consisting of an exterior shell
or inclosure of the same length as one of the conductor sections, and containing a
section of the main or supply conductor, one of the said conductor sections and the
contact devices belonging to the latter, substantially as described.
16. The combination with a continuous insulated main conductor and a series
of separate insulated conductor sections and contact devices for bringing the
insulated sections separately into electric connection with the main conductor, of a
conduit consisting of a series of conduit sections, each conduit section consisting of
an exterior shell or inclosure of the same length as one of the conductor sections
and containing a section or length of the main or supply conductor, one of the
said conductor sections and the contact devices belonging to the latter, said
conduit section being provided with a lower tubular part within which the main
conductor is placed, and which contains a filling surrounding said main conductor,
and a groove or channel in its top in which the conductor section is placed and
within which is a mass or body of insulating material supporting the conductor
section and having at one end a recess or chamber within which the said contact
devices are located, substantially as described.
Dated this 7th day of January 1891.
CHARLES K. HARDING,
By L. W., per F. B.