IMPROVEMENTS IN STEAM ENGINES
Year: 1853

page_text: LETTERS PATENT to John Thornborrow Manifold and Charles
Spencer Lowndes, of Liverpool, in the County, of Lancaster,
Engineers, for the Invention: of" IMPROVEMENTS IN STEAM ENGINES."
PROVISIONAL SPECIFICATION left by the said John Thornborrow
Manifold and Charles Spencer Lowndes at the Office of the
Commissioners of Patents, with their Petition; on the 18th January
1853.
We, JOHN THORNBORROW MANIFOLD and CHARLES SPENCER LOWNDES,
of Liverpool, in the County of Lancaster, Engineers, do hereby declaré
the nature of the said Invention for "IMPROVEMENTS IN STEAM ENGINES"
to be as follows:-
This Invention relates to a simple modification of the ordinary double
cylinder expansive, steam engine known as Wolff's, engine, the object
of the improvement being the simplification of the engine details, with
economy of space occupied as well as economy in the consumption of
fuel, with a superior uniformnity of action.

page_text: In accomplishing these objects two cylinders only are necessary, one
being high pressure and the other low pressure, the connecting rods of
the two cylinders or engines being attached to the same crank pin, and
the cylinders being so placed that when the piston of one is at half
stroke that of the other may be at the top or bottom of the stroke, so
that the discharge steam escaping from the small high pressure cylinder
at the termination of its stroke is directed into the larger low pressure
expansive cylinder when the latter is at half stroke.
This arrangement forms a compound or combined engine of power
equivalent to an engine with a pair of low pressure cylinders, but only
requiring the steam necessary for working the single high pressure
cylinder, whilst an excessive initial steam pressure may be used without
unduly straining the parts of the engine.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Thornborrow Manifold and Charles Spencer
Lowndes in the Great Seal Patent Office on the 13th July 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we,
JOHN THORNDORROW MANIFOLD aud CHARLES SPENCER LOWNDES, of
Liverpool, in the County of Lancaster, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of January, in the
year of our Lord One thousand eight hundred and fifty-three, in the
sixteenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said John Thornborrow Manifold and
Charles Spencer Lowndes, Her special license that we, the said John
Thornborrow Manifold and Charles Spencer Lowndes, our executors,
administrators, and assigns, or such others as we, the said John Thorn-
borrow Manifold and Charles Spencer Lowndes, our executors, adminis-
trators, and assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term therein ex-
pressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel

page_text: Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN STEAM
ENGINES," upon the condition (ainongst others) that we, the said John
Thornborrow Manifold and Charles Spencer Lowndes, by an instru-
ment in writing uuder our hands and seals, should particularly describe
and ascertain the nature of our said Invention, and in what maimer
the same is to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
○ NOW KNOW YE, that we, the said John Thornborrow Manifold
and Charles Spencer Lowndes, do hereby declare the nature of our said
Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement,
reference being had to the accompanying Drawings, and to the letters
and figures marked thereon, that is to say:
.
Figure 1, on our Sheet of Drawings is a side elevation of one of our
combined expansion" engines arranged as an oscillating marine engine.
Figure 2, is a corresponding plan of the same. The entire engine is
carried by the main base plate A, resting on the ship's 'floor or kelson B,
in the usual way; on this base are cast the two trunnion bearings C, D,
for carrying the trunnions of the high and low pressure cylinders E; F.
As regards all its general features the engine is constructed in the usual
way, the two cylinders being so set with regard to each other and to the
main crank shaft G, that their rods shall each act upon a single crank
pin with the same effective operation as a common double engine with
two cranks at right angles to each other. With this view the trunnion
journals are so arranged that the axes of the two cylinders shall work
at or near a right angle with each other. For example, in the position
delineated in our Drawings the piston rod H, of the small high pressure
cylinder E, is in a line coincident with the longitudinal centre: line of
the crank I, whilst the piston rod J, of the larger low pressure cylinder
which is jointed to the same crank pin is at or near a right angle with
the longitudinal centre line of the crank. The initial high pressure
steam from the boiler is led into the trunnion of the small cylinder by
the pipe K, and the power thus obtained is transmitted, from, this,

page_text: cylinder to the crank on the main shaft through the piston rod E...As
the parts stand in our Drawings, the high pressure steam having carried
the piston of the cylinder E, up to the top of its stroke, the used steani
is just being discharged from the lower end of the cylinder for expansion
in the larger cylinder F.; 'and as the slide valve of the. latter-cylinder:is
at this moment full or nearly full open, it follows that the exhausting
steam passes into this larger cylinder; and acts upon its piston at the
most effective part of its stroke. The high pressure slide valve is at L,
and the exhaust steam passes from it along the horizontal pipe M, and
enters the valve chest N; of the larger-cylinder, the final discharge from
this cylinder taking place through the pipe O, into the condenser. Aš
the crank. goes round the reverse 'exhaust action obviously occurs,' and
steam from the top side of the small cylinder passes off to the "reverse
side of the low pressure piston. In this way the arrangement is in
reality a high and low pressure engine combined, each exerting the same
power or nearly so upon the crank, and each therefore acting so as to
turn the crank at a regular uniform rate-without unduly straining any
part of the machinery.....
•
;.
Having now described and particularly ascertained the nature of our
said Invention, and the manner in which the same is or may be used or
carried into effect, we would observe; in conclusion, that we do not con-
fine or restrict ourselves to the precise details or arrangements which
we have had occasion to describe or refer to, as many variations may be
made therefrom without deviating from the principles or main featurės
of our Invention; but what we consider to be novel and original, and
therefore claim as the Invention secured to us by the herein-before in
part recited Letters Patent,.is,
First, the general arrangement and construction of steam engines,-as
herein-before described..-
Second, the system or mode of combining a single high pressure
engine with a single low pressure engine on what is known as the Woolf
principle, so that the two may actuate a single crank, each-engine giving
out the same or nearly the same amount of power to secure uniformity
of motion and strain,

page_text: Third, the system or mode of constructing an oscillating double
cylinder expansion or Woolf's engine with the axes of the cylinders at
an angle with each other, and both pistons working on one and the
same crank.
In witness whereof, we, the said John Thornborrow Manifold
and Charles Spencer Lowndes, have hereunto set our hands and
seals, the Ninth day of July, One thousand eight hundred and
JOHN T. MANIFOLD.
(L.B.)
CHARLES S. LOWNDES. (L.S.)
JOHN T. MANIFOLD.
(1.8.)
CHARLES S. LOWNDES. (L.S.)