Improvements in Electrical Traction, and Apparatus therefor.
Year: 1894

page_text: Date of Application, 28th Sept., 1894-Accepted, 21st Sept., 1895
COMPLETE SPECIFICATION.
Improvements in Electrical Traction, and Apparatus therefor.
We, MAURICE HUTIN, of 46 Rue Caumartin, Paris, Engineer, and MAURICE
LEBLANC, of 63 Allee du Jardin Auglais, Le Rainey, Seine et Oise, France,
Engineer, 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:-
This invention relates to means of communicating electric energy to an electric
motor, on a railway, tramway or other vehicle without making contact with the
main conductor, which may be led along an insulating conduit underground or may
be carried overhead. We shall describe apparatus for effecting communication
with an underground conductor, referring to the accompanying drawings.
Fig. 1 is a diagram illustrating the principle of action,
Fig. 2 is a side view and Fig. 3 a transverse section of a car to which our
invention is applied,
Fig. 4 being a plan of the inductor.
Fig. 5 illustrates diagrammatically a modification of the inductor and its
connections.
Figs. 6 and 7 illustrate diagrammatically the course of the main conductor for a
double line and for two separate single lines.
Assuming X Y Fig. 1 to represent a main conductor traversed by alternating
currents, then if an inductor abcd having the convolutions of its coils parallel
to X Y be placed near X Y there will be induced in the coils currents depending
for their electro motive force on the intensity and frequency of the main currents.
By introducing a condenser C in the circuit of the inductor between it and a
motor M, the self induction may be nullified and even though the induction be
smiall in a coil, the necessary energy may be obtained by multiplication of coils or
increase of frequency of alteruation. Instead of a condenser, other known means
of nullifying self induction may be employed, such as a voltameter in which
polarisation is utilised, or a thermoelectric pile without beating or cooling the
junctions of the metals.
The main conductor E is arranged under the track, it may be in an insulating
conduit, and on the car is fixed on a suitable frame T the inductor G, the currents
from which are led to a motor M. This, as shewn in Fig. 2, has its axis connected
by a universal joint e to a sliaft o made in parts sliding in a aleeve m; and this, by
a worm V, works a wheel on the driving axle, to which the motor might obviously
be connected by other suitable gearing. The bobbin G is fixed us near the ground
as is consistent with safety on a wooden platform A of considerable area.
core of G is a bundle of iron wires which pass through the bobbin and are spread
out as shewn in Fig. 4 over the platform A, so as to utilise a large portion of the
magnetic field resulting from the main conductor currents.
The
Suitable conductors from G lead through condensers or their equivalents and
suitable switches in the car body D to the motor M.
The difference of potentials between the two electrodes of a condenser is pro-
portional at each instant to the charge which it has received, that is to say to the
algebraic sum of the quantities of electricity which have continuously traversed the
conductor closed across the condenser.
Every apparatus susceptible of developing an electro motive force of the same
nature, that is to say proportional to the algebraic sum of the quantities of

page_text: electricity which will have traversed the conductor closed across this apparatus can
evidently be substituted for a condenser in all the applications in which it is
proposed only to develop similar electro motive forces.
It will be so, in particular, if it is proposed to act upon the phase of an alternating
current produced by a given alternating electro motive force.
Now if a current is caused to traverse a thermo electric chain, by virtue of the
phenomenon of Peltier, the fact is established that there is transmission of heat
from the junctions of a certain parity to the junctions of the other parity.
If the duration of the passage of the current in one direction is so short that
the diffusion of heat by radiation or direct conductibility can be neglected, the
difference of temperature established between the junctions of different parities
is very sensibly proportional to the sum of the quantities of electricity which have
traversed these junctions.
But then the thermo electric pile becomes the seat of an electro motive force
which is itself proportional to the differences of temperature thus determined.
It results from this that, if an alternating current be caused to traverse a thermo-
electric chain, this will be the seat of differences of temperature at each instant
proportional to the algebraic sum of the quantities of electricity which have
traversed the chain;
These differences of temperature produce in their turu electro motive forces
which are proportional to them, the thermo electric chain can be substituted for a
condenser whenever the apparatus is only required to produce electro motive forces
of this nature.
In order to vary the driving power, it is preferred to make the inductor up of
several separate coile as shewn in Fig. 5, each coil, of which 4 are shewn, having a
separate lead to its condenser C and switch R, and then all the leads uniting in the
circuit of the motor M. One or more of the coils can then be cut out of circuit
according to the power required. When the line is double, as indicated by Fig. 6,
the main conductor can be led from the generator S along the one line and back by
the other; or as shewn in Fig. 7, two separate lines may be worked from one
generator S. Obviously, instead of an underground conductor, an overhead con-
auctor might be employed, currents being induced from it in a similar way, by an
inductor arranged on the top of the car.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
clain is-
1. The herein described method of communicating electric energy from a main
conductor of alternating currents to a motor on a vehicle by means of currents
induced from the main. without any contact being made therewith.
2. For operating in the manner set forth above, the combination of a main
conductor underground or overhead, an inductor placed on the vehicle as near
as convenient to the main, and a condenser or other appliance for nullifying
self induction introduced between the inductor and the motor, substantially as
described.
Dated this 28th day of September 1894.
ABEL & IMRAY,
Agents for the Applicants.