1
United States 'Patent Office. Patent No.
A designates core, which may magnetic 75
when desired. The other termi
nal the secondary connected earth
and preferably also the primary.
3 side elevation and part section, modi
fied forms induction-coil made accord
ance with invention. 85
When two coils are used transmission
system which the currents are raised a
high potential and then reconverted alower
potential, the receiving-transformer will be
constructed and connected the same man- 90
ner the first—that say, the inner cen
ter end what corresponds the secondary
of the first will connected line and the
Other end earth and the local circuit or
that which corresponds the primary the 95
first.)
To all whom may concern:
Be known that citi
zen the United States, residing New
York, the county and State New York,
5 have invented certain new and useful Im
provements Electrical Transformers, of
which the following specification, refer
ence being had the drawings accompany
ing and forming part the same,
io The present application based upon an
apparatus which have devised and employed
for the purpose developing electrical cur
rents high potential, which transformers
or induction-coils constructed the princi-
15 pies heretofore followed the manufacture
of such instruments are wholly incapable of
producing practically utilizing, least
without serious liability the destruction of
the apparatus itself and danger persons
20 approaching handling it. may depart from
or vary this form, however, the particulars
50 hereinafter specified. SerialH
o, 628,453. 593,188, dated November 3,1897.
SPECIFICATION forming part letters.
ApplicationfiledM
arch 20,1897. Fig.
B the secondary coil, wound upon said
core generally spiral form.
The improvement involves novel form of
transformer induction-coil and system
for the transmission electrical energy by
means the same which the energy the
25 source raised much higher potential
for transmission over the line than has ever
been practically employed heretofore, and the
apparatus constructed with reference the
production such potential and to
30 not only free from the danger injury
from the destruction insulation, but safe
to handle.
The type coil which the last-named
features are present the flat spiral, and this
45 form generally employ, winding the primary
on the outside the secondary and taking
off the current from the latter the center
or inner end the spiral.
NIKOLA TESLA, YORK, Y.
C the primary, which wound around
in proximity the secondary. 60
In using these coils connect one end the
secondary, that proximity the pri
mary,to earth, and orderto more effectually
provide against injury persons the
apparatus also connect with the primary. (N
om
odel. where such
a system illustrated, dynamo con-
. 65
In the accompanyingdrawings, Figure 1is a
diagram illustrating the plan winding and
connection which employ constructing
my improved coils and the manner using -
them for the transmission energy over long 70
distances. Fig. 2is side elevation, and Fig.
ELECTRICAL TRA NSFORMER.
In constructing improved transformers
I employ length secondary which ap
proximately one-quarter the wave length
of the electrical disturbance the circuit in- —
eluding the secondary coil, based the ve- 55
locity propagation electrical disturb
ances through such circuit, or, general, of
such length that the potential the terminal
of the secondary which the more remote
from the primary shall its maximum. One terminal 80
of the latter will the center the spiral
coil, and from this the current taken to
line for other purposes. this end construct induc
tion-coil transformer which the primary
and secondary coils are wound arranged
35 such manner that the convolutions the
conductor ofthe latter willbe farther removed
from the primary the liability injury
from the effects potential increases, the
terminal point highest potential being
40 the most remote, and that between adja
cent convolutions there shall the least pos
sible difference potential. such case also the line-wire should
be supported such manner avoid loss
by the current jumping from line objects
in its vicinity and contact with earth—as,
for example, means long insulators, 100
mounted, preferably, metal poles, that
in case leakage from the line will pass
harmlessly earth
