CERTAIN IMPROVEMENTS ON STEAM ENGINES
Year: 1821

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANZ
ANTON EGELLS, of Brittania Terrace, City Road, in the County of Middlesex,
Engineer, send greeting.
WHEREAS His present Majesty King George the Fourth, in and by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Ninth day of November last, for Himself, His heirs and successors,
did give and grant unto me, the said Franz Anton Egells, my exors, adñiors,
and assigns, His special licence, full power, sole privilege and authority, that
I, the said Franz Anton Egells, my exors, admors, and assigns, and every of
them, by myself and themselves, or by my and their deputy or deputies,
servants or agents, or such others as I, the said Franz Anton Egells, my exors,
admors, or assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, my Invention of
"CERTAIN IMPROVEMENTS ON STEAM ENGINES," within that part of the United
Kingdom of Great Britain and Ireland called England, the Dominion of
Wales, and Town of Berwick-upon-Tweed, and also in all His Majesty's
Colonies and Plantations abroad; in which said Letters Patent there is
contained a proviso obliging me, the said Franz Anton Egells, by an instru-
ment 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

page_text: performed, and to cause the same to be inrolled in His 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 thereto had, will more fully appear.
NOW KNOW YE, that in compliance with the aforesaid proviso, I, the
said Franz Anton Egells, do hereby declare that my said improvements upon
steam engines, and the manner in which the same are carried into effect, are
illustrated by the Drawings contained in the skin following this Specification,
and are particularly ascertained by the following description (that is to say):-
The chief part or foundation of my said improvements, and which I call my
primary improvement, inasmuch as it governs nearly all the rest, by enabling
me to construct a steam engine in a very compact, firm, convenient, and
economical form, consists in a peculiar parallel motion for communicating the
power of the steam from the piston rod to the crank on the axis of the fly-wheel
without the intervention of an oscillating beam, and consequently with a great
saving of expence in the construction and of friction in the working of the
engine, and also giving facility to the making of the whole engine portable.
And I do further declare that my improvements of a secondary nature consist, in
the arrangement of the various parts of the engine in a compact, firm, portable,
and easily accessible form. The particular modes of carrying these my
improvements into effect which I by preference adopt are shewn in the
Drawings herein-before mentioned, where Figure 1 represents a side view of
the steam engine; Figure 2 a view of that end of the engine in which the
pumps are placed; Figure 3 a plan of the frame-work of the case of the
engine, and of the parts attached to it; Figure 4 a plan of the upper
frame, and parts attached to it; Figure 5 a view of the principal parts
of that end of the engine which is opposite to the pumps, including a section
of the valve box. The same letters of reference are used to point out the
same parts in the different views. A, the cylinder; B, the steam pipe; C, the
exhausting pipe; D, the connecting rod; E, E, two rods parallel to and united
with the piston rod g, by means of the cross bar F, and having two collars
below turning on the studs fixed on the lower ends of the connecting
rod D; H, H, H, H, four straight rods to guide the motion of the lower ends
of the connecting rod D, and of the rods E, E, in a direction parallel to the
piston rod; I, the main crank; j, the fly-wheel; K, the shaft and arms for
moving the side valve; L, the condenser, shewn by dotted lines; M, the air-
pump, shewn also by dotted lines; N, the cold water pump; Ü, the warm
water pump; P, a box wherein the cold water from the pump is discharged,
and falls through the pipe Q, into the cistern c; R, the piston of the air-pump;

page_text: S, the piston of the cold water pump; T, the piston of the warm water pump.
These three pistons or plungers are turned truly on their outsides, and the
packing of each is contained between the upper part of the pump and a ring
surrounding the piston. The packing rings are filled with oil or grease to
lessen the friction, and to prevent the air from entering into the pumps.
u, u, a pair of rods, which, by means of the cross bar X, and three collars
connect the pistons R, S, T, to the crank V; W, W, two friction rollers which
guide the piston rod of the air pump in a parallel direction; a, a, two
eccentric pullies; (y), the excentric rod; z, z, two rollers on the upper arm of the
shaft K. In cases where it is required occasionally to reverse the motion of the
engine I apply a rod to each of the excentric pullies x, x, and by putting one
of these rods out of connection, and the other in connection with the arm of
the shaft K, a reverse motion is effected. a, a box wherein the warm water from
the air pump is discharged, and partly taken up by the pump O, and driven
towards the boiler. The remainder of the water flows away, together with the
excess of cold water from the cistern c, through the pipe b, shewn by the dots
in Figure 3. d, the steam and exhausting valve box. Figure 5, No. 2, a plan
of the packing boxes of the slide valve, shewn also in section in Figure 5;
C, C, C, three screws in each packing box to move three pieces of metal
(shewn by dots), and press the packing against the slide (f); g, a cavity which
is filled with oil or grease, in order that it may soak into the packing,
and prevent the air from entering into the valve box. Figure 6, a front view
of the slide i, i, Figure 5, two friction rollers which go up and down between
the guide rods H, H; (K, K,) two frames in which the rollers revolve; 1, a
piece which goes across through the rod E, to which the middle parts of the
roller frames K, K, are jointed; m, m, screws that go through the upper parts
of the roller frames and into the rod E; m, m, wedges by which, in conjunction
with the screws m, m, the roller frames are adjusted to bring the rollers
in contact with the guide rods H, H. Figure 7, an end view of one of the
friction rollers, and its frame. A similar pair of guide rods, rollers, and
frames are placed at the opposite side of the cylinder. Figure 8, a section of
the main piston; o, a cavity between the lid and bottom of the piston to
contain oil or grease; p, one of a number of small holes all around the
circumference of the cavity for the oil or grease to pass through and soak into
the packing from behind. Figure 9 a side view, Figure 10 an end view,
and Figure 10, No. 2, a plan of a cylinder of a steam engine of great power,
where it, is necessary to have a long stroke; in which case I place the guide
rods ffff, for the parallel motion under the cylinder, in order to have the

page_text: engine standing low and solid; a, the main crank; b, b, b the cross bars; c, the
cylinder; d, d, d, d, connecting rods; e, piston rod; ffff, guide rods; g, a
cross bar which holds the guide rods to their proper distances; h, h, friction
rollers; i, i, the roller frames; k, k, screws for adjusting the roller frames;
1,1, wedges for holding the rolling frames to their adjustment against the
screw heads; m, the valve box. Figure 11, a section of one of the guide
rods ff, ff, which have flat sides, against which the friction rollers work. The
parts, in Figure 10, on the opposite side of the cylinder, are to be the same as
those shewn in the Drawings. Figure 12 and Figure 13 represent views,
and Figure 14 a plan of a cylinder, where the connecting rods a, a, a, a, are
combined with a ring b, which encompasses the cylinder and contains two
friction rollers c, c, which work up and down against the sides of the cylinder
when the engine is in motion.
The parallel motion described in Figures 1, 2, 3, 5, 7, 9, and 10, con-
stituting my primary improvement, the invention of which I claim, might be
executed in different forms, and would allow of various other ways of
arranging the parts of the engine, which I need not describe, because I
consider the modes herein specified as having a preference over any variations
that may be made, except in cases where local circumstances may require
an altoration in the shape or position of any given part; but I do not
lay claim to all the various parts so specified, separate from my parallel motion
and arrangement, because most of those parts have heretofore been in public
use. In the steam engines that I have described there will be a-saving of
metal, of workmanship, of room, and of friction, and every part is so placed
that a person can easily get at it to repair any injury it may receive. Engines
of great power, erected according to these my improvements, require no strong
buildings to give them stability, as they are fastened only to their own founda-
tions. For steam boats, or for other purposes where a fly wheel, would be
inconvenient, I apply two such cylinders and parallel motions as before
described to two cranks standing at right angles to each other on the same
axis. The condenser, air pump, cold and warm water pumps, and their
connections stand in the middle between the two cylinders, and serve
for both.
In witness whereof, I have hereunto set my hand and seal, the Twenty-
third day of March, in the year of our Lord One thousand eight
hundred and twenty-two.
FRANZ ANTON EGELLS. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Twenty-third day of March,
in the year of our Lord 1822, the aforesaid Franz Anton Egells came before
our said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Inrolled the Seventh day of May, in the year of our Lord One thousand
eight hundred and twenty-two.