A CERTAIN. IMPROVEMENT OR IMPROVEMENTS IN THE CONSTRUCTION OF STEAM ENGINES
Year: 1825

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LEMUEL
WELLMAN WRIGHT, of Princes Street, Lambeth, in the County of Surry,
Engineer, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain and Ireland,
bearing date at Westminster, the Twenty-first day of October, One thousand
cight hundred and twenty-five, in the sixth year of His reign, did, for Himself,
His heirs and successors, give and grant unto me, the said Lemuel Wellman
Wright, His especial licence, that I, the said Lemuel Wellman Wright, my
exors, admors, and assigns, or such others as I, the said Lemuel Wellman
Wright, my. exors, admors, 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, my Invention of
"A CERTAIN. IMPROVEMENT OR IMPROVEMENTS IN THE CONSTRUCTION OF STEAM
ENGINES;" in which said Letters Patent is contained a proviso obliging me, the
said Lemuel-Wellman Wright, 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 the 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
Lemuel Wellman Wright, do hereby declare the nature of my said Invention,

page_text: and in what manner the same is to be performed, are particularly described
and ascertained in the following description thereof (that is to say) :-
My improvements on steam engines consist in certain improvements on a
Patent granted by His late Majesty King George the Third to Moses Poole,
of the Patent Office, Lincoln's Iun, in the County of Middlesex, Gentleman,
for "Certain Improvements on Steam Engines," communicated to him by
a Foreigner then residing abroad; which said Letters Patent bear date at
Westminster, the Fifteenth day of December, in the year of our Lord One
thousand eight hundred and seventeen, the Specification of which was duly
inrolled in His Majesty's High Court of Chancery.
My present improvements apply to ratatory steam engines or steam wheels,
and consist in an improved mode of constructing the joints of the levers or
valves which act as pistons, and also in rendering them and the wheel steam-
tight. These improvements will be seen by reference to the Drawings hereto
annexed, and the following description thereof (that is to say):-
"
Fig. 1 represents the interior of the rotatory engine, one of the side plates
being removed; Fig. 2 is a cross section of the same: the similar letters of
reference are used to denote the same parts in these two Figures.
A, A, A,
is the outer cylindrical case in which the steam wheel acts. B, B, B, is tho
steam wheel. C, C, are the leaves or valves. D, D, are steel pins affixed to
to the leaves, which turn in cylindrical sockets, and constitute the joints.
E, E, are the trip leavers affixed to and extending from the back of the steel
pins D, and when the same wheel B is made to turn the ends of the said
leavers strike against the tappets or friction roller F (fixed to the side plate),
and causes the leaver C to be thrown up into a radient position, as shewn by
the leaf marked C 1, in Fig. 1. G is the steam stop. H, H, II, is the steam
channel. I is the induction pipe. K is the eduction pipe. The steam
being admitted by the induction pipe I, passes into the steam channel II,
where, by its pressure acting against the radient leaf C 1, the wheel is driven
round, and when the leaf has passed the eduction pipe k the steam escapes
through the said pipe, and the leaf is shut down, and made to lie in a recess
formed in the periphery of the wheel. The shutting down of the said leaf is
effected by the curved part of the steam stop G. In the meantime the
opposite leaf will have been thrown up into its radient position of the tappet or
friction roller F, as herein-before described, and the pressure of the steam will
now act upon the said last-mentioned leaf, and so continue the rotatory motion of
the wheel upon its axle M, from which said axle the power is communicated to
work other machinery. The mode by which I construct the hing joint of the leaf
C is as follows:-I cast the steam wheel B at the parts where the joints are to

page_text: be formed in the shape shewn by the red dots at C 1, and then bore a cylin-
drical hole through the solid part of the wheel for the socket of each hing. A
cylindrical steel pin is then grouned so as to fit accurately into the hole, the
pin being afterwards attached to the leaf by screws. I then remove a part of
ог
other
the metal from one side of the said hole, leaving so much of the hole as will
form a recess or socket that shall embrace about three fourths of the circum-
ference of the pin D. The leaf having been affixed to the pin by screws, as
herein-before said, is then slidden sideways into the socket, and secured from
falling out by attaching the packing in front, and the trip leaver D to the back
part of it. The leaf and its pin are thus allowed to act in the socket joint; a
portion of the solid part of the wheel at a enters a recess in the front of the
leaf, as shewn at 6, Fig. 4, and a projecting piece c, Figs. 8 & 5, falling into a
recess in the wheel behind the leaf. A shoulder is thus formed to support the
said leaf when in the radient position. The particular form and construction
of the leaf or valve is shewn in the several detached views of it. Fig. 3
exhibits the back part; Fig. 4, the front; and Fig. 5, the end. Fig. 6 is the
end face plate of Fig. 4, and Fig. 7 is the same view as Fig. 4, the face plate
being removed for the purpose of shewing the form, position, and action of the
metal packing and the springs which press the pieces outward. The packing
of the steam stop G is effected by the introduction of a piece of brass
metallic substance d, having springs in the recess behind it for the purpose
of keep it close against the periphery of the wheel B, and is an iron plate
affixed by screws on the top of the stop G in order to secure the packing.
The packing for preventing the escape of the steam between the sides of the
wheel, and the side plates L, L, (see the section Fig. 2,) is produced by brass
rings f, f, placed flat against the sides of the wheel B, B, and these rings are
affixed to iron rings 9, 9, which are fitted accurately into the side plates L, and
are pressed towards the sides of the wheel B by vertical springs h, h, the force
of which said springs may be increased by screwing up the studs that the
springs coil round. In order to accommodate the irregularities of expansion
between the brass and the iron, these brass packing rings are made in seg-
ments, as shewn in Fig. 8... The segments are held against the iron rings by
countersunk screws passed through holes or slots, which allow the segments to
slide as the brass expands or contracts. Between the junctions of these seg-
ments there are wedge-formed pieces i, i, pressed outwards by springs kc, k, for
the purpose of keeping the edge of the brass packing against the fittings of the
plates L, L, (see Fig. 2,) in order to prevent the passage of steam behind the
wheel. The axle M (Fig. 2) is fitted to the wheel B in the ordinary way. Its
bearings 1, 1, are hardened steel collars, two, at each end, which are made

page_text: separate from the spindle, and are hardened, tempered, and fitted on, and
between them a recess is formed for the reception of oil or other anti-attritious
matter by the introduction of a smaller collar m. The collars 7, 7, are made slightly
conical, that the brass collars a, a, may be screwed down in order to tighten
them as the metal wears away. On the outside of the brass collars there are
stuffing boxes Z, Z, kept tight by screws to prevent any escape of steam that
might have insinuated itself behind the wheel. Fig. 9 represents another
steam wheel, in which the joint of the leaf or valve C is constructed in a
different manner to the foregoing. Fig. 10 is a cross section of the said steam
wheel, the same letters of reference pointing out the similar parts in these two
Figures; and where there are no alterations in construction, the same letters of
reference are used to denote the similar parts in Fig. 1 and 2, and also in
Fig. 9 and 10. Fig. 11 is a front view of the leaf. Fig. 12 is an end view
of the same. Fig. 13 exhibits the interior of the leaf with the metallic
packing and springs, the front plate, Fig. 14, being removed. Fig. 15 is an
edge view of Fig. 13. The leaf is shewn at Fig. 16 in the same position as
Fig. 11, the brass packing, the springs, and the hinge plate a being removed.
Fig. 17 is an edge view of Fig. 16; the hinge plate is shewn detached at
Fig. 18, and its edge at Fig. 19. The packing and the springs of the leaf aro
made in the same way as described before in reference to Fig. 3 to 7. The
mode of forming the joint of the leaf will be fully understood by reference to
Fig. 16, 17, 18, and 19, the leaf and the hinge plate being put together and
secured by a pin B, as seen in Fig. 15, with the trip lever c attached. The
particular advantages of this construction of leaf joint or hinge is, that the
workmanship does not require the same accuracy of fitting as the joint first
described, for in this instance a perfect steam-tight stop is produced by the
front of the leaf C at d bedding against the edge of the hinge plate a, as
will be clearly perceived by inspecting Figures 9, 12, and 15. The brass
rings which pack the sides of the steam wheel B, represented at e, e,
in Fig. 10, may be constructed in the same manner as herein-before
described.
In describing the nature of my improvements on steam engines I have
found it necessary to exhibit and explain the general construction of a steam
wheel, or rotatory steam engine, upon the plan proposed under the Patent
granted to Moses Poole, as above recited. I therefore beg to state explicitly
my claims of improvement are enumerated under the following heads:-
1st. In the form of the joint, by which a greater quantity of the surface of
the leaf and the steam wheel are made to come in contact with or apply
themselves to the joint pir, and in making the pin of a separate picce, and

page_text: afterwards attaching it to the leaf or valve herein-before described, so that the
whole is thereby rendered more steam-tight.
2dly. The manner of making the steam stop, as herein-before described.
3dly. The construction and application of the herein-before mentioned brass
and hardened steel collars when used in conjunction with each other, in the
manner and for the purpose herein-before described.
4thly. In the manner of effecting a steam-tight joint between the lower
edge of the leaf or valve and the edge of the joint plate, as herein-before
described, and as is shewn in the Drawing.
5thly. The arrangement and construction of the brass or other metallic
segments as packing attached to the iron ring by screws, as before described,
when applied to rotatory steam wheels.
In witness whereof, I, the said Lemuel Wellman Wright, have hereunto
set my hand and seal, this Twenty-first day of April, in the year of
our Lord One thousand eight hundred and twenty-six.