459,772, dated September 22,1891.)
To all whom concern:
Be known that Nikola Tesla, sub
ject the Emperor Austria, from Smiljau,
Lika, border country Austria-Hungary, re-
5 siding New York, the county and State
of New York, have invented certain new and
useful Improvements Electro-Magnetic
Motors, which the following specifica
tion, reference being had the drawings ae
ro companying and forming part the same.
In application filed February 18, 1889,
Serial No.
Figure part sectional view the two
motors; Fig.
NIKOLA TESLA, NEW YORK, Y. avoid this objection and start up
a synchronizing motor which these condi- 55
tions obtain the object present in
vention. and are dia
grams modified dispositions the two mo- 85
tors.
A
pplicationfiledA
pril6, 1889. will observed, the 65
first place, that both motors are run without
commutators any kind, and, secondly, that
the speed the torque motor may higher
than that the synchronizing motor, will
be the case when contains fewer number 70
of poles sets poles, that the motor will
be more readilyand easilybrought speed. The smaller or
.
SPECIFICATION forming part Letters Patent No. 2,an end view the synclironiz- 80
ing motor; Fig. Hence in
all instances heretofore when these “synehro-
20 nizing motors,” they are termed, have been
run, some means have been adopted bring
the motors synchronism with the gen
erator, approximately so, before the alter
nating current the generator applied to
25 drive them. therefore mount both upon the same 90
shaft the field-magnets the synchro
nizing and Cof the torque motorbeingsecured
to the same base The preferably larger
synchronizing motor has polar projections on
its armature, which rotate very close prox- 95
imity the poles the field, and other
respects conforms the conditions, now-
well understood, that are necessary secure
synchronous action. 306,165. 300,220,1have shown and described
an improved system operating this class
of motors, which consists, broadly, wind-
30 ing arranging the motor such manner
that means suitable switches could
be started multiple-circuit motor, one
operating progression its magnetic
poles, and then, when speed, nearly
35 so, converted into ordinary synchronizing
motor, one which the magnetic poles
were simply alternated.
As well known, certain forms alternat
ing-current machines have the property, when
connected circuit with alternating-cur
rent generator, running motor syn-
15 chronism therewith; but while the alternating-
current will run the motor after has at
tained rate speed synchronous with that
of the generator will not start it. (N
om
od
el. prefer, however, to
wind the pole-pieces the armature, with 100
closed coils this obviates the employ
ment sliding contacts. Hence
with current very high number al
ternations the motor may not respond prop
erly.
This invention involves several novel and
useful features.nited States Patent Office.
In the drawings have illustrated the in
vention.
ELECTRO-MAGNETIC MOTOR. some cases, as
when large motor used and -when the
number alternations very high, there is
40 more less difficulty bringing the motor
to speed double multiple-circuit mo
tor, for the plan construction which renders
the motor best adapted run synchro
nizing motor impairs its efficiency torque
45 double-circuit motor under the assumed
conditions the start. SerialN
o., ASSIGNOR THE TESLA ELECTRIC
COMPANY, SAME PLACE. diagram the circuit connections
employed; and Figs. This will readily
understood, for large synchronizing mo
tor the length ofthe magnetic circuit the po
lar projections and their mass are great that
50 apparently considerable time required for
magnetization and demagnetization.
Thirdly, the synchronizing motor may con
structed soas have much morepronounced
tendency synchronism without lessening 75
the facility with which started. have therefore combined two mo
tors, one synchronizing motor, the other a
multiple-circuit torque motor, and the
latter bring the first named speed, 60
and then either throw the whole current into
the synchronizing motor operate jointly
both the motors. end view and part sec
tion the torque double-circuit motor;
Fig.
Inasmuch neither motor doing any
work while the current acting upon the
other, prefer rigidly connect the two arma
tures
