AN IMPROVED ENGINE FOR COMMUNICATING POWER FOR MECHANICAL PURPOSES
Year: 1830

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ERICSSON, of the New Road, in the County of Middlesex, Engineer, send
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-fourth day of July, in the first year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
John Ericsson, His especial licence, that I, the said John Ericsson, my
executors, administrators, and assigns, or such others as I, the said John
Ericsson, my executors, administrators, or assigns, should at any time agree
with, and no others, from time to time and at all times during the term
of years therein expressed, should and lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed, and
also all His Majesty's Colonies and Plantations abroad, my Invention of "AN
IMPROVED ENGINE FOR COMMUNICATING POWER FOR MECHANICAL PURPOSES;" in
which said Letters Patent is contained a proviso obliging me, the said John
Ericsson, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of my said Invention, and in what manner the
same is to be performed, and to cause the same to be inrolled in His said Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Ericsson, do hereby declare the nature of my said Invention to consist in

page_text: producing a rotary motion applicable to mechanical purposes, by causing
steam to pass through channels forming part of a hollow revolving chamber,
which channels are so formed as to oppose a resistance to the passage of the
steam, in such manner as to cause the said hollow chamber to revolve.
And in further compliance with the said proviso, I, the said John Ericsson,
do hereby describe the manner in which my said Invention is to be performed,
by the following description thereof, reference being had to the working Draw-
ing annexed, which is made to a scale, and represents one of my said improved
engines of fifty horses power, applied to the purpose of communicating power
for mechanical purposes, and reference being also had to the figures and letters
marked upon the said Drawing; that is to say:-
DESCRIPTION OF THE DRAWING.
Figure 1 is a plan of one of my said improved engines. A, A, is the fixed
or stationary outer casing of the engine; and c, c, is the frame supporting the
engine. D is the steam pipe from the boiler; and E is the exit pipe by which
the steam escapes, either into a condenser or into the atmosphere, as may be
most convenient. F is the axis of the hollow revolving chamber before mentioned,
which chainber, from its peculiarly rapid and uniform motion, I call a fly drum,
and which revolves within the outer casing A, A; this axis rests on the
bearing B, which bearing is in fact a friction roller, on which the axis is kept
by the lesser roller P on one side, and by the brass step p on the other, as will
be seen hereafter in another Figure; the other end of the axis rests also upon
a similar friction roller, on which the axis is kept by a brass step, but which in
this view is concealed by the exit steam pipe E being placed above it.
It will be useful here to state that similar letters of reference will be used to
denote similar parts in all the Figures.
Figure 2 is a view of my said improved engine applied to the purpose of
communicating power for mechanical purposes as aforesaid, and representing
a transverse section of its principal parts, the parts coloured green being the
media by which I communicate the power of the engine to other machinery
not applicable immediately to the axis F of the fly drum. A, A, is a stationary
outer casing forming a steam chamber, and fixed firmly to the framework c, c,
es shewn in Figure 1. D is the steam pipe from the boiler, opening into the
steam chamber A, A; and E is the exit pipe for the steam after it has performed
its office. F is an axis passing through the steam chamber A, carrying the
hullow drum or chamber before mentioned, and supported at one end on the
broad friction roller B, and at the other on the narrow friction roller G, as
before described, and kept on those rollers by the stop rollers P and the brass

page_text: step p. II is the said hollow drum or chamber, which, from its peculiarly
rapid and uniform motion, as before stated, I call the fly drum; this fly drum is
fixed upon the axle F by means of the boss I, I, and turns with it. Within
this fly drum are three fixed or stationary vanes or fans, 2 of which are here
shewn at J, J, one being broken off to shew the interior of the fly drum at H.
These vanes are attached to a collar a, a, through which the axle F passes
freely, and which screws to the side of the steam passage K, K, thereby
holding the vanes stationary while the fly drum revolves on the surface L, L,
of the fly drums; channels of a particular form are made leading to aper-
tures opening into the drum; these channels, as here shewn, are of an
oblong square shape, formed in the surface L. L, of the drum, each being
an inclined plane with sides, as at r, and dipping inwards and open to the
internal part of the drum at s. In this Figure two of these channels are repre-
sented, and the effect produced by them and the internal arrangement of the
engine as before described, will be as follows:-Steam being admitted into
the close steam chamber A, A, through the steam pipe D, it will force its way
through the channel r to the apertures s, into the fly drum, which will be
driven round by the action of the steam upon the inclined planes of the said
channels, while the steam, prevented from following the course of the drum by
means of the stationary vanes J, J, will find its way out of the drum into the
passage K, K, through the opening e, c, and thence into the exit pipe E, causing
a constant revolution of the drum H and axis F as long as steam is admitted
into the steam chamber. f is an end view of one of the said channels, and it
will be seen that the vanes J, J, must have notches or spaces cut in them to
allow these channels to pass by them in the course of the revolution of the fly
drum. With reference to these channels, it is absolutely necessary to observe
that they must be so constructed that the length of the channel shall always
exceed its depth in such proportion that the channel itself shall always move
at a greater speed than the steam acting against its bottom,-for when the
length is to the depth as, for instance, 2 to 1, the motion of the acting
steam towards the bottom of the channel will only be one half as rapid as
the motion of the channel itself. W is a close box filled with water or other
suitable fluid, to keep the axis F and rollers B and P from heating. In
order to make this box tight, where the axis F passes through, a collar
X is fixed upon it, furnished with a rise or flange, the greater velocity of
which, in consequence of its increased size at that part will prevent the
water from escaping during the revolution of the axis; the roller G, by which
the other end of the axis F is supported, is furnished with a similar water or
oil box.

page_text: Figure 3 is a separate perspective view of one of the channels; and it will
be proper here to state, that, though an inclined plane is the best shape for the
bottom of the channel, yet if it be sunk equally much below the surface of the
drum at both ends, provided always that the length of the channel exceeds
its depth, it will act well.
Figure 4 is a separate view of a fly drum, with its boss I, I, and with the
channels made on the periphery of the drum, which is equally effective, and
for which purpose it will be seen that the edge of the drum is made flat, instead
of sloping, as at Figure 2.
Figure 5 is a plan of the inner side of the surface L, L, of the fly drum,
shewing channels both on that surface, as represented in Figure 2, and on the
edge of the drum, as represented in Figure 4, which may sometimes be
desirable. The channels are marked r; and the parts marked I represent the
stationary vanes.
Having now described my said improved engine, and its mode of acting; it is
only necessary further to observe, that when it is required to apply the power of my
engine to any machinery not directly attached to its axis, it should be done by
means of motion wheels or rollers pressed down upon the axis F, and to be turned
by the friction of that axis against them, their perepheries being made some-
what rough by slight fleuting, for the revolutions of that axis will be found too
rapid to admit of cogged wheels-being-used-with-advantage.
The parts
coloured green, in Figure 2, represent such motion wheels or rollers as aforesaid,
as also part of the 'arrangements by which the necessary pressure is caused
upon the axis F to set the said rollers, and the machinery connected with
them, in motion. M, M, is a motion wheel, or broad roller, placed vertically
over and resting upon the axis F of the fly drum. N, N, is the axis of the
roller, and as this axis serves for the main or driving shaft, to which machinery
may be attached in the ordinary way, I call the roller M the driving roller.
O, O, are two rollers for causing friction or pressure, and which I therefore call,
by way of distinction, the pressure rollers. On the axis T, T, of these rollers I
fix a lever, to which I hang weights or attach springs, in order to give
the required pressure; but this will be better shewn in Figure 6. This
Figure represents an end elevation of my said engine, and the rollers
aforesaid. C is the cast-iron framing on which is cast the knob or boss;
Q, the short arm of the lever R, which turns on the axis T of the roller O, acts
against this boss; and V being a slide brass moving freely up and down as the
driving roller M, M, is raised or depressed, it is evident that if weights be
added to the lever R, any required pressure may be obtained on the axis F of
the fly drum.

page_text: Now, whereas it is evident that if my said engine were so modified and
arranged that the steam was forced directly from the boiler into the fly
drum through its center, in which case the full pressure of the steam would
be inside instead of outside of the drum, and escaped out into the steam
cha ber through such channels as aforesaid, offering the resistance aforesaid,
but opening out from the drum instead of into it, the object of my said
Invention would be equally obtained, for the exit pipe might then lead from the
steam chamber A, A, instead of from the fly drum:
And whereas I claim as my Invention the improved engine herein-before
described, and particularly the steam chamber A, A, with the fly drum H, and
its particularly proportioned channels revolving within the said steam chamber,
and which I call my Improved Engine for Communicating Power for Mechanical
Purposes; and such my Invention being, to the best of my knowledge and belief,
entirely new, and never before used within that part of His said Majesty's
United Kingdom of Great Britain and Ireland called England, His said Domi-
nion of Wales, or Town of Berwick-upon-Tweed, nor in any of His said
Majesty's Colonies and Plantations abroad, I do hereby declare this to be my
Specification of the same; and that I do verily believe this my said Specifica-
tion doth comply, in all respects, fully and without reserve or disguise, with
the proviso in the said herein-before in part recited Letters Patent contained:
wherefore, I hereby claim to maintain exclusive right and privilege to my
said Invention.
In witness whereof, I, the said John Ericsson, have hereunto set my
hand and seal, this Twentieth day of January, in the year of our Lord
One thousand eight hundred and thirty-one.
JOHN (L.s.) ERICSSON.