CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF STEAM ENGINES AND STEAM BOILERS OR GENERATORS
Year: 1828

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
CLEGG, of Chapel Walks, Liverpool, in the County of Lancaster, Engincer,
send greeting.
WHEREAS His most Excellent Majesty King George the Fourth, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Twentieth day of March, in the ninth year of His reign, did
give and grant unto me, the said Samuel Clegg, my exors, adiñiors, and
assigns, His special licence, full power, solc privilege and authority, that I,
the said Samuel Clegg, my exors, adiiors, and assigns, 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, "CERTAIN
IMPROVEMENTS IN THE CONSTRUCTION OF STEAM ENGINES AND STEAM BOILERS OR
GENERATORS;" in which Letters Patent there is contained a proviso obliging
me, the said Samuel Clegg, particularly to describe and ascertain the
nature of my said Invention, and in what manner the same is to be per-
formed, by an instrument in writing under my hand and seal, 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, relation being thereunto had, will more fully appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Samuel Clegg, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by these presents and in and by the Drawings hereunto
annexed and hereby referred to.
My improvements in the construction of the steam engine and steam boilers
or generators are as follows:-

page_text: First, my improvement, which refers to the steam engine, consists in a new
form and construction of that part of a steam engine called the working
cylinder and piston, when used with high-pressure steam, either employed
expansively or not, and I shall continue to use the term "cylinder" to
express the improvement, on account of its being used for the same purpose
as cylinders in other engines, although it differs from the figure of a cylinder
according to the mathematical definition of that word. My improved
working cylinder and piston are constructed in the following manner-The
cylinder, instead of being straight as in engines in general use, is in the shape
of a bent tube or hollow ring, forming a segment of a circle, being above
ninety degrees and less than two hundred degrees; but I prefer a segment of
one hundred and eighty degrees, by which means I obtain an important
increase in the length of the stroke of the piston without increasing the bulk
of the engine, at the same time I am enabled to regulate with great facility
the unequal force of steam when used expansively, as I shall herein-after
describe. A cross section of the interior of this cylinder in its best form is a
square, which is convenient for using a metallic packing to it. One end of
this cylinder is closed, excepting the aperture for the admission and exit of
steam, by the usual valves, and the other end is closed by the piston or plunger
passing through a stuffing box, and the cylinder has no other aperture or
communication with any part of the engine except by means of the piston.
The piston or plunger must correspond in form with the interior of the cylinder,
but be somewhat less in thickness, so as to move easily within it, and instead
of a piston rod of a different diameter to a piston as in common cases, the
piston or plunger should be of the same dimensions throughout; but it must
be longer by ten or twenty degrees more of the segment of the circle than the
working cylinder, so that when inserted in the cylinder it may nearly fill it and
project sufficiently for the purpose of connecting it at one end with the other
parts of the engine. I shall describe one mode of connecting the working
cylinder and piston with the engine in my references to the Drawings (which,
however, 1 do not claim as part of my Invention), but other well known plans
may be adopted as circumstances require. In using steam expansively the
great desideratum is to equalize the force of the steam throughout the whole
stroke of the piston. This is easily effected in a working cylinder and piston
of the construction I have described, by placing weights at the projecting ends
of the piston, so that when high-pressure steam is first let into the cylinder
against the end of the piston, such weight will diminish the power on the
engine, and as the piston rises in the circle the effect of the weight will gra-
dually diminish, until the weight is vertical to the axis of the arm to which it

page_text: is attached; as the piston is ascending, and before it has obtained its greatest
height, the steam is shut off by any of the well known means, according to the
length of the stroke of the piston, and thus (the steam decreasing in elasticity)
the weighted arm beginning to descend beyond the perpendicular assists the
power in the same proportion as it previously impeded it, and consequently the
aiding power of the weight increases as the force of the steam becomes dimi-
nished, and an uniform pressure, or nearly so, is kept up. The quantity of
weight must be measured by the force of expansiveness in the steam employed.
In marine or locomotive engines, where weights would be objectionable, this
regulation may be effected by connecting the projecting end of the arm
by means of a jointed rod with a piston working air-tight in an open-topped
cylinder, closed at the bottom, so that the lifting of such piston against the
atmosphere will produce the same effect as the weights, and the same in
descending. I do not claim the first invention of the application of either
mode of equalizing the pressure of the steam before described. A cylinder
and piston thus constructed may be applied to the working of a single engine
acting only on one piston, and the steam being let out when the stroke
is completed, for the purpose of allowing the piston to re-enter, after the
manner of the well known single engines. But in most cases I prefer the use
of two distinct cylinders and pistons, as pointed out in the Drawings, directing
the power alternately to the two pistons, the joint action thus constituting a
double engine. When an engine of great power is required, I prefer connect-
ing more than two cylinders together to gain the power rather than making
the cylinders too bulky.
Having defined my Invention as to the working cylinder and piston, I shall
now describe it by reference to the Drawings, which are drawn with the
several parts in proportion.
MUSL
No

page_text: Fig. 2 is a ground plan, and Fig. 3 a front elevation of parts of an engine
constructed as a double engine, shewing one mode of connecting the working
cylinder and piston with the other parts of an engine. The same letters in all
the Figures (where used) refer to the same parts. B, B, and B, B, represent
the two working cylinders, and C, C, and C, C, the two pistons, one of which
is in the opposite situation to the other, viz, the plunger end of one opposite
to the closed end of the other, and one nearly fills the working cylinder, whilst
the other is nearly out; thus, the steam being admitted into and discharged
from each cylinder alternately by means of valves, a constant motion is kept
up after the manner of a common double engine. T, T, is the framework on
which the engine is mounted; F, the shaft working on steps or brasses
secured to their places by the framework and connected with the two pistons
by the two arms D, D. On the shaft F is also fixed a double lever or crank
M, M, for the purpose of giving motion to the double sector H. The
distance between the centres of the pins of the cranks M, M, is equal to about
half the space through which the cranks move when in action, and the length
of these cranks must be governed by the length of the crank which is attached
to the fly wheel shaft; parallel to this face of the double crank M, M, and at a
short distance from it, stands the double sector H, the lower end of which
moves on a centre or gudgeon V, and to the upper part of which in the centre
is secured a pin or gudgeon J, projecting at right angles from it on each side.
Between these upper and lower gudgeons, and at the upper part of the
sector, are two grooves L, L, of the same width as the diameter of the rollers
on the crank pins and at the saine distance between their centres, as are the
pins of the double crank M, M. In these grooves the rollers work, and as
they move backward and forward give the same motion to the sector. The
pins or gudgeons J, J, projecting from the top of the sector, are fastened to a
connecting rod W, W, for the purpose of communicating the motion from the
sector to the crank R and the fly wheel shaft S, in the usual way; P, P, are
rollers on the crank pins for lessening the friction against the sector. I have
purposely omitted inserting in the Drawings the valves, the mode of opening
and closing them, the governors. and other minor parts of the engine, and I
have refrained from entering into a long detail of the operation of the parts of
the engine which are drawn, because they are constructed on well known
mechanical principles, and I do not claim any part of them, but I thought it
might be useful to shew my manner of connecting my improved working
cylinder and piston to the principal parts of a steam engine.
Secondly, my Invention, which refers to steam boilers or generators, consists
in causing the whole, or part of them, to rise and fall so as to supply them-

page_text: selves with water, as the water originally put into them evaporates into steam.
This object I effect by suspending the generator on an axis, and balancing it
by means of a lever or weight; as the water diminishes, the generator will
become lighter and rise. The motion thus procured is applied to the opening
of a valve or other aperture for the admission of water into the generator,
which, being thus increased in weight, will again descend, and at the same time
stop the supply of water by closing the valve or other aperture. This plan may
be applied either to one single generator or to several connected together.
The motion obtained by the rising and falling of the generator may be directed
to the purposes I have mentioned by many mechanical contrivances, too
numerous to be detailed. I shall proceed to describe one method, and refer to
the Drawings in No. 2, by way of explanation. In these Drawings several
generators are connected together. The same letters where used refer to the
same parts. The several parts are drawn in proportion to each other.
Fig. 4
is a longitudinal section, with brickwork. Fig. 5 a ground plan, without the
brickwork. Fig. 6, an end view, without the brickwork. The generators C, C, C,
consist of tubes about seven inches in internal diameter, and about eight feet in
length. A is the fireplace; B. B, the flue. The ends of the generators which
are over the fire A are made steam tight, and those ends of the generators are
fastened together by a bar J, by means of screws through the bar on to the top
of the generator. The ends of the bar J extend outside the brickwork on each
side of the fireplace sufficiently far to be suspended by means of rods to the
short ends of two levers cr beams K, (constructed like the common steel yard,
and turning on the fulcrum Z), one on each side the generators. The longer
division of these levers extends beyond the end of the brickwork (containing
the generators) furthest from the fire, and the levers are there united by a
bar N, to the centre of which is suspended a weight M, which will just balance
the weight of the generators when about half full of water. To any part
between the short end of either of the levers and its fulcrum is attached a
perpendicular rod L, communicating with a valve or cock attached to a forcing
pump for supplying the generators with water. The end of the tubes furthest
from the fire are inserted into and firmly rivetted in a vessel or receiver D,
about one inch wide, and a little longer than the whole breadth of the gene-
rators inserted therein, and the depth exceeding, at the bottom of the receiver,
the outside diameter of one generator. The width of the receiver gradually
tapers towards the upper part. The upper part of the receiver D is closed.
The water is forced into the generator by a common forcing pump, of the
requisite size, through a pipe E, running through one of the gudgeons II, and
down the receiver along the generator to within a short distance of the end
over the fire. The steam, when gencrated, passes into the receiver and

page_text: through a hole in the other gudgeon H¹ and pipe F; the steam thus obtained
may be applied to the working of a steam engine by the usual means, or the
steam may be applied to many other purposes, for example, for heating places
or substances. The generators and receiver, fixed together as described, move
upon the gudgeons H, H', which lie upon bearings on the brickwork; a safety
valve O must be added, of the usual construction. The operation of the gene-
rators will be as follows:-Supposing a fire to be lighted, and the generator
half filled with water (which is the proper supply), and balanced by the weight,
as the water decreases in the generators by evaporation the generators will
become comparatively lighter, and rise, and the lever rising will, by the rod L,
open the valve and admit the water into the generator until it becomes so
heavy as again to descend. The cylinder and piston above described and the
generator or boiler also above described, may be constructed of various metals,
and the various parts may be made of such substances as are suited to the
nature of the work to be performed and the degree of strength, power, or
durability required.
I have described one mode of carrying my Invention into effect, but various
plans may be adopted. It is unnecessary to enter into detail of the particular
dimensions applicable to various cases, attention to the general remarks I have
made will be sufficient to lead any person conversant with the manufacture of
steam or power engines generally, to adopt the dimensions to any particular
case, and the arrangement and construction of many of the minor parts may
be modified according to the size of the engine, the situation in which the
apparatus is placed, and the circumstances governing the same, without at all
deviating from my Invention as I have defined the same.
And lastly, although I have described many parts of an engine which are
not new, I have done so solely for the purpose of rendering my Invention more
clearly understood, and not as claiming them.
In witness whereof, I, the said Samuel Clegg, have hercunto set my hand
and seal, this Twelfth day of September, in the ninth year of the
reign of His Majesty King George the Fourth, and in the year of
our Lord One thousand eight hundred and twenty-eight.
Signed, sealed, and delivered, by the
within named Samuel Clegg, in the
presence of,
JAMES BURRA,
SAM CLEGG. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Twelfth day of September, in the
year of our Lord 1828, the aforesaid Samuel Clegg came before our said
Lord the King in lis Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
5 written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Inrolled the Twentieth day of September, in the year of our Lord One