IMPROVEMENTS IN STEAM ENGINES
Year: 1874

page_text: LETTERS PATENT to Frederick Arthur Paget, of 1, Seymour Chambers,
York Buildings, Adelphi, London, and of 13, Riemer Gasse Stadt,
Vienna, for the Invention of "IMPROVEMENTS IN STEAM ENGINES.”—A
communication from Friedrich Wannieck and Hermann Köppner,
residnig in the City of Brünn, Moravia, in the Empire of Austro-
Hungary. Engineers and Manufacturers.
Sealed the 15th June 1875, and dated the 17th December 1874.
PROVISIONAL SPECIFICATION left by the said Frederick Arthur Paget
at the Office of the Commissioners of Patents, with his Petition,
on the 17th December 1874:
I, FREDERICK ARTHUR PAGET, of 1, Seymour Chambers, York Build-
ings, Adelphi, London, and of 13, Riemer Gasse Stadt, Vienna, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
STEAM ENGINES," a "communication to him from Friedrich Wannieck
and Hermann Köppner, persons resident in the City of Brünn, Moravia,

page_text: in the Empire of Austro-Hungary, Engincers and Manufacturers, to be
as follows:-
:-
These improvements relate to engines in which the steam is to be
used expansively, and the degree of expansion regulated by the engine
governor acting on cut-off expansion valves according to the variations
in the load on the engine.
The kind of valves used are, by preference slide valves of the known
form, consisting of a pair of steam boxes sliding on the cylinder port
surfaces, and plate slide valves working on the backs of such main slide
valves. The steam flows into the cylinder ports from the back of the
steam box or main valve, which valve is alternately covered and
uncovered by the plate or cut-off expansion valve. There are two pairs
of each of these valves working upon the inlet and exhaust ports at the
ends of the steam cylinder. The two main slide valves are held together
by a rod so as to be worked together by an excentric, a cam, or other
suitable mechanism. On this main valve is a double cross head. One
head of this double cross head is keyed on the main valve rod, the other
parallel head can slide on the two separate parallel rods for working the
two cut-off valves, and it carries two tappets oscillating on pins and
fitted below with catches. Between these tappets are two stops in
connection with and actuated by the governor.
The ends of the rods for working the plate cut-off valves are fitted
with heads of steel hardened and suitably shaped so as to butt against
the appropriate catch when the same drops down. On each of these
same expansion valve rods there is also fixed a plunger which can slido
to and fro in a bush fitted on the valve chest, the inner end of the said
plunger being under the pressure of the steam. On each of the opposito
ends of the expansion slide rods is further a small piston fitting into an
air-tight cylinder closed at the outer end, and arranged in such wise
that the motion outside of the piston compresses the air contained within
the same.
By means of the arrangement as described on the main valve boxes or
main valves being moved by the centric, the plate valves on their backs
participate in this motion and without changing their positions
relatively to the main valves as long as the tappets catch the heads of
the expansion valve rods. But as soon as one of the tappets comes in

page_text: contact with its appropriate stop the tappet is lifted up past the head
of its expansion valve rod, the valve rod is unlocked, the valve thereby
released, and the pressure of the steam acting on the plunger propels
back the rod and cut-off valve, thereby closing the steam inlet in the
main valve. The exact instant when this takes place depends upon the
actual position of the stop when coming into contact with the tappet,
and this position itself depends upon the action of the governor.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Arthur Paget in the Great Seal Patent,
Office on the 17th June 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
ARTHUR PAGET, of 1, Seymour Chambers, York Buildings, Adelphi,
London, and of 13, Riemer Gasse Stadt, Vienna, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventeenth day of December, in the
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Frederick Arthur Paget,
Her special licence that I, the said Frederick Arthur Paget, my
executors, administrators, and assigns, or such others as I, the said
Frederick Arthur Paget, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN STEAM ENGINES," a com-
munication to me from Friedrich Wannieck and Hermann Köppner,
persons resident in the City of Brünn, Moravia, in the Empire of Austro-
Hungary, Engineers and Manufacturers, upon the condition (amongst
others) that I, the said Frederick Arthur Paget, my executors and
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be

page_text: performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Frederick Arthur Paget, do hereby
declare the nature of my said Invention, and in what manner tho
same is to be performed, to be particularly described and ascertained
in and by the following statement :—
These improvements relate to engines in which the steam is to be
used expansively, and the degree of expansion regulated by the engine
governor acting on cut-off expansion valves according to the variations
in the load on the engine.
The kind of valves used are, by preference slide valves of the known
form, consisting of a pair of steam boxes sliding on the cylinder port
surfaces, and plate slide valves working on the backs of such main slide
valves. The steam flows into the cylinder ports from the back of the
steam box or main valve, which valve is alternately covered and
uncovered by the plate or cut-off expansion valve. There are two pairs
of cach of these-valves-working-upon-the inlet and exhaust ports at the
ends of the steam cylinder. The two main slide valves are held together
by a rod so as to be worked together by an excentric, a cam, or other
suitable mechanism. On this main valve rod is a double cross head.
One head of this double cross head is keyed on the main valve rod, the
other parallel head can slide on the two separate parallel rods for working
the two cut-off valves, and it carries two tappets oscillating on pins and
fitted below with catches. Between these tappets are two stops in
-connection with and actuated by the governor.
The ends of the rods for working the plate cut-off valves are fitted
with heads of steel hardened and suitably shaped so as to butt against
the appropriate catch when the same drops down. On each of these
same expansion valve rods there is also fixed a plunger which can slide
to and fro in a bush fitted on the valve chest, the inner end of the said.
plunger being under the pressure of the steam. On each of the opposito
ends of the expansion slide rods is further a small piston fitting into an
air-tight cylinder closed at the outer end, and arranged in such wise
that the motion outside of the piston compresses the air contained within
the same.

page_text: By means of the arrangement as described on the main valve boxes or
main valves being moved by the excentric, the plate valves on their
backs participate in this motion, and without changing their positions
relatively to the main valves as long as the tappets catch the heads of
the expansion valve rods. But as soon as one of the tappets comes into.
contact with its appropriate stop, the tappet is lifted up past the head,
of its expansion valve rod; the valve rod is unlocked; the valve thereby.
released, and the pressure of the steam acting on the plunger propels
back the rod and cut-off (valve, thereby closing the steam inlet in the
main valve. The exact instant when this takes place depends upon the
actual position of the stop when coming into contact with the tappet,
and this position itself depends upon the action of the governor.
Having now set forth the nature of this Invention, the exact mode
of carrying it out will be further explained by means of Drawings.
Fig. 1 in the accompanying two Sheets of Drawings is the side
elevation; Fig. 2, the longitudinal cross section; Fig. 3, the cross
section; and Fig. 4, the plan of the steam cylinder of a horizontal engine
fitted with valve gear on this system.
The Figures A, B, C, and D, indicate the more important positions of
the main slide valves a, a', and cut-off expansion valves c, c'.
.
In Fig. 2, the main slide valves a, a', are shewn held together by
means of the rod b. They can be worked by an ordinary excentric, a
cam, or other suitable mechanism. In the same Figure c, c¹, are
common plate cut-off expansion valves working on the backs of the said
valves in the manner well known to engincers. d is a cross head or
cross piece, one head of which is keyed or otherwise fixed on the main
valve rod b, but the other head sliding on the ends of the separato
rods e, et, for working the cut-off slides. This cross head carries two
tappets g, g', (Fig. 1) oscillating on pins f, f¹, and fitted below with
catches. On the inner ends of the two expansion valve rods e, e¹, which
ends can slide within the cross head d are secured or otherwise fixed
heads h, h', (Figs. I. and II.) of steel hardened. On each of the outer
ends of the said valve rods are small pistons which slide in air-tight
cylinders i, . These pistons slide to and fro within the cylinders i, i,
and the back stroke of the said pistons can be regulated by means of the
set screws k, k', according as the said screws are set to let more or less.

page_text: or no air out. On the said expansion valve rods there are further
plungers,, which can slide to and fro in the bushes m, m¹. The said
bushes are fitted steam-tight on the valve chest. Instead of two shorter
plungers or pistons with an intermediate space, as shewn in Fig. 2, a
single solid plunger as indicated in the separate Figs. x and z may be
employed. A rod n (Figs. 1, 3, and 4, connected with the governor of
the engine conveys its motion to the stops o, o¹.
The action of the valve gear above described is now as follows:—If
the pair of valves a and c in Fig. 2, which are shewn at the centre of
the stroke, be supposed to be at the beginning of the stroke of the valve
(as in Fig. A), then the passage for the inlet of the steam in steam
valve a is quite open, and the tappet 9 has by means of its own weight
fallen down behind the steel head h. On the forward motion of the
main valve a to the right, the cut-off valve c is forced to go with it, and
without changing its position relatively to the valve a as long as the
tappet g does not come in contact with the stop o. When this does
take place the tappet g with its catch is lifted past the steel head h and
unlocked. At this instant the pressure of the steam in the steam chest
acting on the plunger 7 releases the cut-off valve c, propelling back the
rod and valve, and thereby closes the steam inlet in the main valve a.
This unlocking and closing of the valve will necessarily take place earlier
or later, according as the stop pin o of the tappet g has a lower or higher
position respectively. As the position of the stop depends upon
the action of the governor the amount of expansion is therefore
regulated by the same, and the supply of steam at once adjusted to the
actual load on the engine. On the release and running back of the cut-
off or expansion valve c, the steam valve a necessarily continues to slide
back below the said valve c to the end of the stroke, returning to the
beginning of the stroke as described. The steam inlet of the main
valve a is then again left open by the expansion valve, the tappet g falls
with its catch behind the steel head has before, and so on.
It need scarcely be observed that what has been described applies as
well to the other end of the cylinder and to the other half of the valve
gear belonging thereto.
1 T

page_text: that what is claimed as novel in the same is the arrangement as
described for effecting a variable expansion in steam engines or any
colourable imitation thereof.
In witness whereof, I, the said Frederick Arthur Paget, have
hereunto set my hand and seal, this Fifth day of June, in
the year of our Lord One thousand eight hundred and seventy-
five.