ELECTRIC GENERATOR. 75
In practice have found that the best re
sults are secured the employment an
air spring, that is, body confined air or
gas which compressed and rarefied the
movements the piston, and order se- 80
cure spring constant rigidity prefer to
employ separate chamber cylinder con
taining air the normal atmospheric press
ure, although might any other press
ure, and which works plunger connected 85
with carried the piston rod.
In the construction engine above re
ferred have followed and applied this
35 principle, that say, employ cylinder
and piston which any suitable manner I
maintain reciprocation steam gas
under pressure. This known true all
30 cases where the force which tends bring the
spring movable system into given position
is proportionate the displacement.)
To all whom concern:
Be known that esla, citizen
of the United States, residing New York, in
the county and State New York, have in-
5 vented certain new and useful Improvements
in Electric Generators, which the follow
ing specification, reference being had to
the drawings accompanying and forming a
part the same,
to application even date herewith,
Serial No.
It well known mechanical principle
that spring possessing sensible inertia
be brought under tension, being-
stretched, and then freed, will perform vi-
25 brations which are isochronous, and to
period, the main, dependent upon the ri
gidity the spring, and its own inertia that
of the system which mayform imme
diate part.
ApplicationfiledAugust 19,1893.United States Patent Office,
NIKOLA TESLA, NEW YORK, Y. The length 65
the stroke will vary with the pressure, but
the rate period reciprocation more
dependent upon the pressure applied drive
the piston, than would the period oscil
lation pendulum permanently maintained 70
in vibration, upon the force which periodically
impels it, the effect variations such force
being merely produce corresponding varia
tions the length stroke amplitude of
vibration respectively.483,562.
SPECIFICATION forming part Letters Patent No. the case ofthe engine referred
to,the ports are soarranged that the movement
of the piston within the cylinder either di
rection ceases when the force tending impel 55
it and the momentum which has acquired
are counterbalanced the increasing press
ure the steam compressed air that end
of the cylinder toward which moving, and
as its movement the piston has shut off 60
agiven point, the pressure that impelleditand
established the pressure that tends return it,
it then impelled the opposite direction,
and this action continued long the
requisite pressure applied.
In order that present invention maybe
more readily understood will explain the
conditions which are observed order
2o secure this result. (H
omodel. 511,916, dated January 1884. The main
reason why engine heretofore has been
capable producing results this nature is
that has been customary connect with
the reciprocating parts heavy fly-wheel 90
some equivalent rotary system relatively
very great inertia, other cases where no
rotary S
3rstem was employed, certain re
ciprocating engines tools, regard has
been paid theobtainmentof the conditions 95
essential the end which have view,
nor would the pressure such conditions in
said devices appear result any special
advantage.
Such engine have described affords 100
a means for accomplishing result heretofore
unattained, the continued production elec
tric currents constant period, impart
ing the movements the piston core or
. the moving piston to
the cylinder, case the latter reciprocate
40 and the piston remain stationary, spring is
connected soas maintained vibration
thereby, and -whatever may the inertia of
the piston the moving system and the
rigidity the spring relatively each other,
45 provided, the practical limits w'ithin which
the law holds true that the forces which tend
to bring the moving system given position
are proportionate the displacement, are not
exceeded, the impulses the power impelled
50 piston and the natural vibrations the spring
will always correspond direction and coin
cide time. SerialNo. 483,563,1have shown and described
a form engine invented me, which, un
der the influence applied force such as
the elastic tension steam gas under
15 pressure, yields oscillation constant
period
