IMPROVEMENTS IN STEAM ENGINES, WHICH ARE ALSO APPLICABLE WHOLLY OF IN PART TO PUMPS AND OTHER MOTIVE MACHINES
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
MAUDSLAY, of the firm of Maudslay, Sons, and Field, of Lambeth, in the
County of Surrey, Engineers, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-sixth day of
January, One thousand eight hundred and fifty-two, in the fifteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Joseph Maudslay, my exors, adññiors, and assigns, Her especial
licence, full power, sole privilege and authority, that I, the said Joseph
Maudslay, my exors, adññiors, and assigns, or such others as I, the said Joseph
Maudslay, 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 therein
years
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, and in the Islands of
Guernsey, Jersey, Alderney, Sark, and Man, and also in all Her said Majesty's
Colonies and Plantations abroad, my Invention of "IMPROVEMENTS IN STEAM
ENGINES, WHICH ARE ALSO APPLICABLE WHOLLY OF IN PART TO PUMPS AND OTHER
MOTIVE MACHINES;" in which said Letters Patent is contained a proviso that I,

page_text: the Joseph Maudslay, shall cause a particular description of the nature of my
said Invention, and in what manner the same is to be performed, by an
instrument in writing under my hand and seal, to be enrolled in Her Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said in part 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
Joseph Maudslay, hereby declare that the nature of the said Invention, and
in what manner the same is to be performed, are fully described and ascer-
tained in and by the present Specification thereof, reference being had to the
Drawings hereunto annexed (that is to say):-
My said Invention, in so far as regards steam engines, has relation to that
class of engines commonly called "rotary engines," because of the rotary motion
thereof being produced by the direct application of the force of steam, and
consists of an improved arrangement of parts for the purpose represented in
Figures 1, 2, 3, and 4; Figure 1 being a longitudinal section of an engine
constructed according to said arrangement; Figure 2, a plan thereof in
section; Figure 3, an end view; and Figure 4, a cross section on the line c, d.
A, B, are two cylinders of different diameters, the lesser of which is designed
to revolve within the larger one, but eccentrically in regard to it, so that the
outside of the smaller cylinder shall, throughout its entire length and circum-
ference, come in contact with the inside of the larger one as they revolve
together, but only a portion or line lengthways of the cylinder being in contact
at the same movement. C is a piston plate which projects from the inside of
the larger cylinder, and as that cylinder revolves moves in and out of a
recess D, formed in the side of the inner cylinder A. The ends A and B of
both the cylinders are turned truly, and fit exactly the one into the other. The
larger one has a hollow trunnion formed on each end, and the two trunnions
revolve on fixed bearings G1, G2, which are provided with set screws for exactly
adjusting the position of the cylinders in relation to each other. F is a spindle
or axis which carries the smaller cylinder A, passing right through the centre
of it, and also through the hollow trunnions G³, G, and resting at its ex-
tremities in the bearings H, H. The two sets of bearings G1, G2, and H, H,
are parallel to but not in the same line with one another, and the hollows of
the trunnions of the large cylinder are of such size as to allow the axle of the
smaller one to pass clear through them in its eccentric position. I, I, are
boxes which contain the packing for the axles, and also serve as passages for
conveying the steam to and through the trunnions. K, K, are openings made
in the end of the small cylinder, through which the steam is admitted into the

page_text: interior of that cylinder, L, L, are passages for the admission of steam
behind or on one side of the piston plate, and M, M, are passages for the
escape of the steam on the opposite side or from in front of the plate. N is
a four-way cock for starting, stopping, regulating, and reversing the engine.
The mode of operation of the engine is as follows:-Steam is passed through
the hollow axis or trunnion G at one end of the large cylinder into the
interior space between the two cylinders; that is to say, into the space which
for the time being is behind or on one side of the piston plate; and this steam
pressing against the piston plate carries it round, and along with it both the
larger cylinder to which it is attached, as also the smaller cylinder with which
it is interlocked (by means of the piston plate). As the two cylinders revolve
together the piston gradually loses its effective area of propulsion (that is to
say), the area of piston exposed between the cylinders is gradually diminished
until the point of contact between the two cylinders, or dead point of each
revolution, is reached, over which point the engine is carried by the momentum
of the parts in action. After the steam has thus performed its office it passes
off from the opposite side of the piston plate through the hollow trunnion G³
on the other end of the large cylinder, either into the atmosphere or into a
condenser, according as the engine is worked as a condensing or non-condensing
engine.
A modification of the preceding arrangement is exhibited in Figures 5
and 6. Here the large cylinder A is made with an outer steam casing A', and
fitted with false ends adjustable by set screws, and it is divided by a partition
D into two compartments, to each of which there is a separate piston plate E,
the two piston plates being placed in opposite positions in regard to each
other, so that a more uniform power may be obtained throughout each
revolution. And instead, also, of one inner cylinder two (D' and F') are here
employed, one of which is keyed on to the spindle F, while the other is left
loose upon it, and so at liberty to adapt itself to the varying position of the
piston. In this modification the steam may be admitted at one trunnion and
be conveyed through the outer casing formed round the larger of the two
cylinders into the space behind the piston plate or plates, and conveyed thence
through the smaller cylinder to the other trunnion, or the motion of the engine
may be reversed by causing the steam to enter through the smaller cylinder
and pass away through the outer casing of the larger one.
starting and reversing cock.
L is a four-way
Another modification is shewn in Figure 7, which it will be proper to adopt
when it is desired to work the engine on the continuous expansion principle.
The outer and larger cylinder A is made as in Figures 5 and 6, with an outer

page_text: casing A', which is divided by partitions B, B, into two compartments of
different sizes, each of which is provided with a separate piston plate, the two
piston plates being placed in opposite positions to each other. In this. arrange-
ment, also, as in Figures 5 and 6, there are two inner cylinders (D' and F¹)
of different sizes, the larger one of which F¹ is keyed fast to the spindle F,
and the other left loose. The steam is admitted through the trunnion G and
aperture H, H, into the outer casing A', and thence into the
space
behind the
piston plate of the smaller compartment of the large cylinder, from which it
passes through the interior of the small cylinder D' into the outer casing A¹,
when it enters the space behind the piston of the large compartment, where it
acts on the piston by its expansive force, after which it is allowed to pass off
through the interior of the inner cylinder F and the trunnion G, either to the
condenser or to the atmosphere.
A fourth modification is shewn in Figures 8 and 9. A is an annular cylin-
der, which is mounted on a spindle or axis C, which revolves in fixed bearings
D, D. Within the annular space is a ring E, with a groove or opening cut
in it, through which a piston plate or plates B passes, which piston plate or
plates is fixed to the outer and inner ring of the annular cylinder.
The ring E revolves on its own centre in bearings which are fixed eccentri-
cally in regard to the other bearings D, D, so that as the one ring revolves
within the other the outside of the interior ring shall be brought in contact
with the inside of the outer ring of the annular cylinder, whilst at the same
time its interior is in contact with the outside of the smaller ring of the annular
cylinder, thus forming two lines of contact between the annular cylinder and
the internal ring. To allow of the insertion of the interior ring, the large
one (A) is made in two halves as shown. The smaller ring E has a circular
flange P, by means of which it is attached to the outer casings F, F, which
are carried by hollow trunnions G, G. The piston plate B forms the barrier
against which the steam acts, and through the medium of which motion is
communicated from the annular cylinder to the interior ring, so that they shall
revolve together, but each on its own centre. Steam is admitted as in the
arrangements previously described, through one of the trunnions and the holes
k, k, to the back of the piston plate, and escapes from before the piston plate
through the other trunnion and holes shewn by dotted lines at 7,1. The steam
passes from one side of the annular flange P to the other, through the holes
i, i.
Instead of the annular cylinder being fixed on a spindle, as in the ar-
rangement just described, and the internal ring being carried by an outer
casing with hollow trunnions, it may in some cases be found more advanta-
geous to form the hollow trunnions on the former, and carry the latter on a

page_text: circular flange or boss fixed on an axle passing excentrically through the
trunnions.
The different forms of steam engine before described offer in common these
following advantages:-First, their great simplicity, lightness, and compactness,
the working parts being in each case few in number, and these all in balance,
or nearly so, and there being neither valves nor slides nor eccentrics required
for the admission and emission of the steam; second, the directness of their
action; and, third, the great velocity at which they are capable of being unin-
termittingly driven, and without noise or shock. Instead of the piston plate in
the engine represented in Figures 1, 2, 3, and 4, and its modification being
attached to the larger or outer cylinder, as before described, it may be attached
to the smaller or inner cylinder, and made to work in a recess in the outer
one. I prefer to use cylinders, through cones or portions of cones, with the
axles so placed as to bring their surfaces in contact, might be employed. So
also instead of the spindle of the smaller cylinder being employed as the
driving shaft, the motion may be taken from a toothed wheel, and gearing
attached to the outer or larger cylinder. Any other elastic or non-clastic fluid
may be used for working these engines as well as steam.
An arrangement,
which would be particularly suitable for being driven by water, is represented
in Figures 10 and 11. A is an annular cylinder, open at one end, which has
a piston plate P fitted into and revolves on its centre in fixed bearings C, C.
D is an internal ring, made hollow to form a channel for conveying the water
to the back of the piston plate, and which has its centre or axis formed by a
hollow trunnion revolving in the bearing E, which is fixed excentrically to the
bearings C, C. The annular cylinder has at top a circular flange or disc,
which must be sufficiently large to allow for the change of position, as the two
parts revolve together. Water is admitted down the hollow trunnion, and
through the passages f, f, into the space behind the piston, and it is allowed. to
escape from before the piston through the passages 9, 9, in the annular
cylinder. As pumps for raising or forcing water or other fluid, engines on any
of the plans which have been described will be found especially useful, as, in
consequence of the high velocity of which they are capable, and their con-
tinuous rotatory action, a small machine may suffice to discharge a large
quantity of water or other fluid. As blowing machines, too, they will have the
advantage of maintaining a great pressure of blast with a regular and easy
motion.
And having now described the nature of my said Invention, and in what
manner the same is to be accomplished, I declare that the improvements which
I claim are as follows:-First, I claim as my Invention of improvements in

page_text: steam engines the arrangements herein-before described and represented for
obtaining motion by means of two cylinders, revolving on independent centres,
the one within the other, and in such relative orbits that the lesser cylinder
shall during each revolution come throughout its entire length in contact
with the large cylinder; and, second, I claim the application of the said
improved modes of construction, all or any of them, to pumps and other
motive machines.
In witness whereof, I, the said Joseph Maudslay, have hereunto set my
hand and seal, this Twenty-sixth day of July, in the year of our Lord
One thousand eight hundred and fifty-two.
JOSEPH (L.S.) MAUDSLAY.
JOSEPH (L.S.) MAUDSLAY.
Enrolled the Twenty-sixth day of July, in the year of our Lord One
thousand eight hundred and fifty-two.