Thefield-
coils have their terminals binding-posts 60
K, and may either closeduponthemselves
or connected with source direct current
L meaUsof switch The mainorcon
trolling,switch hasfive contacts and '
two levers .. 90
The field-coils are thrown into circuit with
the direct-current source when the1main
switch shifted. (Komodel.
What claim herein invention is—
1. The shaft the armature
carriesthree collecting contact rings D
E.'rotating. (Shown, for better illustration, dif-. 811. When
the motor thus started reached passes the
limit speed synchronous with the genera
tor, connect the coils previously short-
35 circuited with source direct current and
bya change the circuit-connections pro
duce simple alternation the poles.) .I
progressively shift the magnetic poles one
element field the motor alternating
purrentsdifferiňginphase passedthrough
30 independent energizing-circuits and short-
circuit the coils of-the other element. example, with the coils B
50 right ,angles.
wire Contacts and are connected tq
brushes respectively,"through the wires /
P and contact directly connected witfy 75
brush The lever has widened end'/
which may span the contacts When in
such position and with lever contact d,
the alternating currents divide between the
two motor-coils, and reason their dif- 80
ferent self-induction difference current-
phase obtained that, starts the motor ro
tation.to ine April 1C
, 1889,
No.
SPECIFICATION form ing art etters aten No. .)
, all whom, concern': ,
Be known that Nikola Tesla, sub
ject Ofthe Emperotof Austria-Hungary, for
merlyof Smiljan,Lika,bordercountryofAus-
5 tria-Hungary, but nowresiding NewYork,
in the county and Slate'of.
sists the following -m'ethpd: the start.
The motor shown one the ordinary
forms, with field-cores either laminated or
Bolid and with cylindrical laminated arma
ture wound, for.
N c
COMPANY, SAME PLACE.the magnetic poles
of one element until has reached synch
ronous speed and then alternating said poles
and passings directcurrentthrough the coils icc
of the other element, herein set forth.
Collecting springs brushes bear
upon the rings and lead the contacts a
switch,tobehereinafterdescribed.pivoted and connected 65
insulatingcross-bar h,eo move paral
lelism. SerialHo. The
motor then continues, run synchronism;
with the generator.
When the motor has attained the desired 85
speed, the switch shifted!to the position
shown dotted lines—that say, with the
levers/ gresting onpoints ce.connected the
linerwires from source alternating cur
rents .are short-circuited. '“
• The present invention specific way of
a5 carrying out the saine invention; anditcori-.
One, end of'coil connects one ring, as; ■
C, anidone end coil Bconnects with ring 55
The remaining. Thereare manyspecific:
40 ally-different ways which this may car
ried out; but have séléctedonefor illustrat
ing the principle.G
and coll through dead-resistance and 70
wire :Contact0 Connected,with brush F
and Bbil through self-induction-coilS and •.
ELECTRO-MAGNETIC MOTOR.
ferént diameters.
Application SledKay 30,1889. The method operating electro-mag-
.ends areconnected ring E.Qontacfa is-connected-to brush. This illustrated the
annexed drawing, which side view a
motor with diagram the circuits and de-
45 vices used the system.United Patent Office.420.
2. the drawing
accompanyingandformiiigapartofthe same. Thisconnects
up the two ármaturé-coils series, and the
motor will then run'as synchronous motor. These levers are . 401,520,1 have shown and described a
method operating alternating-current mo-
15 tops first shifting rotating theirmag-
netic poles until they had reached passed
a synchronousspeedaud thenalternatingthe
poles, or, other words,by transforming the
motor byachaňgebf circuit-connectionsfrom
ao one operated the action of. New York, have
Invented certain Jiew and useful Improve
ments Methodsof Operating ElectrorMag-
nétic Motors, whichthe followingis ispeci-
io fication, inference being had to. starting; have above stated,
'the field-coils.two more in
dependentenergizing-currents toá motorola
eratedbya single current several acting
as one.
■In patent granted. 418,248, dated December 31,1889. The method operating electro -mag- 95
netic motors, which consists first progress
ively Shifting or
