IMPROVEMENTS IN ROTATORY ENGINES
Year: 1860

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in
the County of Middlesex, and of 166, Buchanan Street, in the City of
Glasgow, North Britain, Gentleman, for the Invention of "IMPROVEMENTS
IN ROTATORY ENGINES."-A communication from abroad by Edward
Scheutz, of Stockholm, in the Kingdom of Sweden, Civil Engineer.
Sealed the 26th February 1861, and dated the 30th October 1860.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson, at
the Office of the Commissioners of Patents, with his Petition, on the
30th October 1860.
I, JO IN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North Britain,
Gentleman,do herebydeclare the nature of the said Invention for "IMPROVE-
MENTS IN ROTATORY ENGINES," a communication from Edward Scheutz, of
Stockholm, in the Kingdom of Sweden, Civil Engineer, to be as follows:-
This Invention relates to a peculiar constructionand arrangement of rotatory
engines, whereby greater facility is afforded for tightening or setting up the
rubbing surfaces, whilst at the same time the efficiency and economy of such
engines are greatly increased.
According to this Invention the cylinder is made slightly conical, and the
internal rotatory piston is of a corresponding form so that by setting up or
adjusting the piston longitudinally inside the cylinder by means of an end
Price 8d.1

page_text: adjusting screw, the rubbing surfaces of the piston and cylinder may be fitted
accurately together when any perceptible wear takes place. The interior of
the cylinder is provided with two or more diametrically disposed stops which
serve to divide the otherwise continuous or annular steam space existing
between the surface of the piston which is grooved or channelled circumfer-
entially for that purpose and the interior cylinder. The grooving of the piston
is so arranged as to leave a projecting flange at each end of the piston and
these flanges alone form the actual contact surfaces between the cylinder
and piston, the grooved part forming a steam space between the two surfaces.
In the interior of this piston are fitted four or more diametrically disposed
radiating slides or diaphragms which are pressed outwards against the inner
sides of the cylinder by spiral or other springs. As these diaphragms pass the
stops above referred to they are gradually forced inwards, and are as gradually
allowed to protrude again after passing the stops by the aid of suitable guide
pieces placed inside the cylinder which act as inclinesto force in the diaphragms.
The steam or other elastic vapour or gas is admitted from a steam chest
formed on the upper surface of the cylinder and provided with a circular slide
valve which is turned by means of a lever handle in such a manner as to
allow of the engine being worked in either direction or stopped as the case
may be. By making the bottom of the groove in the piston of a corresponding
taper to the piston and having the edges of the stops and sliding diaphragms
also inclined so as to correspond to the general taper of the cylinder and piston,
it follows that the whole of the rubbing surfaces may be set up or tightened
with the greatest ease and accuracy by the simple longitudinal adjustment of
the piston as herein-before described.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 30th April 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN HENRY
JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and of 166,
Buchanan Street, in the City of Glasgow, North Britain, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of October, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her reign
did, for Herself, Her heirs and successors, give and grant unto me, the said

page_text: John Henry Johnson, Her special license that I, the said John Henry Johnson,
my executors, administrators, and assigns, or such others as I, the said
John Henry Johnson, my executors, administrators, or 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 "IMPROVE
MENTS IN ROTATORY ENGINES," a communication from abroad by Edward
Scheutz, of Stockholm, in the Kingdom of Sweden, Civil Engineer, upon the
condition (amongst others) that I, the said John Henry Johnson, my
executors, or administrators, by an instrument in writing under my hand
and seal, or under the hand and seal of one of them, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be 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 John Henry Johnson, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the follow-
ing statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say :-
The said Invention relates to a peculiar construction and arrangement of
rotatory engines, whereby greater facility is afforded for tightening or setting
up the rubbing surfaces, whilst at the same time the efficiency and economy
of such engines are greatly increased.
According to this Invention the cylinder is made slightly conical; and the
internal rotatory piston is of a corresponding form, so that by setting up or
adjusting the piston longitudinally inside the cylinder, by means of an' end
adjusting screw, the rubbing surfaces of the piston and cylinder may be fitted
accurately together when any perceptible wear takes place. The interior of
the cylinder is provided with two or more diametrically disposed stops, which
serve to divide the otherwise continuous or annular steam space existing
between the surface of the piston, which is grooved or channelled circumn-
ferentially for that purpose, and the interior cylinder. The grooving of the
piston is so arranged as to leave a projecting flange at each end of the piston,
and these flanges alone form the actual contact surfaces between the cylinder
and pistou, the grooved part forming a steam space between the two surfaces.
In the interior of this piston are fitted lour or more diametrically disposed
radiating slides or diaphragms, which are pressed outwards against the inner

page_text: sides of the cylinder by spiral or other springs. As these diaphragms pass the
stops above referred to they are gradually forced inwards, and are as gradually
allowed to protrude again after passing the stops by the aid of suitable guide
pieces placed inside the cylinder, which act as inclines to force in the
diaphragms. The steam or other elastic vapour cr gas is admitted from a
steam chest formed on the upper surface of the cylinder, and provided with a
circular slide valve, which is turned by means of a lever handle in such a
manner as to allow of the engine being worked in either direction, or stopped
as the case may be. By making the bottom of the groove in the piston of a
corresponding taper to the piston, and having the edges of the stops and
sliding diaphragms also inclined so as to correspond to the general taper of
the cylinder and piston, it follows that the whole of the rubbing surfaces may
be set up or tightened with the greatest ease and accuracy by the simple
longitudinal adjustment of the piston, as herein-before described.
purpose
I
And in order that the said Invention may be fully understood, I shall
now proceed more particularly to describe the saine, and for that
shall refer to the several Figures on the Sheets of Drawings hereunto
annexed thesameletters of referenceindicatingcorresponding parts throughout
all the Figures.
Figure 1 of the Drawings represents a longitudinal section of the improved
rotatory engine taken along the line V-X in Figure 3; Figure 2 is a
transverse vertical section of the same taken along the line y-, in Figure 3;
Figure 3 is a side elevation of the engine; Figure 4 is a detail plan of the
slide valve chamber and circular slide valve, by which the steam or gas may
be alternately conducted to or from the engine, or shut off entirely, as
required, and Figure 5 represents a detached view of one of the fixed stops,
with its curved or inclined guides.
"
A is the cylinder," which is made slightly conical, and encloses the
correspondingly tapered piston B. 3A, 3A, represent the two stops, which
subdivide the otherwise continuous or annular steam space formed by the
recessed or grooved surface of the piston and the interior of the "cylinder" or
outer cone. Any number of pairs of stops may be used, but they should
always be placed diametrically opposite to each other. 'A, 'A, 'A, 'A₁, are
the inclined or curved guides, which are intended to gradually force inwards
the sliding diaphragms of the piston, so as to permit of their passing the stops,
and to allow them to be as gradually protruded again after passing the stops.
B is the conical piston, with its groove or sunk portion B fitting partly against
the stops ³A, 3A, and partly against the inner surface of the "cylinder" when
tightened up by the end screw D and nut D¹; B₁, B₁, Ba B, are the arms

page_text: of the piston B. In small engines these arms may also be used as cases or
sockets for the reception of the sliding diaphragms. 'B₁, 'B., 'B₂, 'B,, are
the cases or sockets of the slides, of which sockets the notches "B,, 'B., "B₂, "B₁,
in the end flanges or collars of the piston are continuations; B is the main
shaft of the engine upon which the piston is keyed; "B₁, 'B₂, 'B, B4, are the
sliding diaphragms, which work easily in their cases or sockets 'B₁, 'B, 'B₁, 'B..
The number of these slides may vary at pleasure. B₁, B2, B3, B4, are the
pins for guiding the helical springs, which tend to force out the slides. These
pins may be either fixed in the slides, as shown in the Drawing, or in the
piston itself. C is the valve chamber, the steam pipe leading from the
boiler, and C3 is the eduction or exhaust pipe leading either to the free
atmosphere or to a condenser, as preferred; C' is the circular or discoidal
slide valve. It is so constructed that by turning it a quarter of a revolution
the engine will be reversed, and by turning it only one-eighth of a revolution
the steam will be shut off, and the engine stopped. This will be easily under-
stood on referring to the plan view, Figure 4. A chamber or recess formed
on the under side of the valve for the escape of the steam to the eduction
pipe, such chamber being made to connect any opposite two of the four pipes
C1, C2, C3, C4, which connect the bottom of the valve chamber or face with
the cylinder. Two apertures are made through the disc of the valve on
diametrically opposite sides thereof, and in such positions as to coincide with
any opposite two of the four openings of the pipes, so as to allow the steam
from the boiler to pass through those two pipes which are thus left open,
whilst the other two pipes or orifices communicate with the exhaust port, as
shown, through the recessed or chambered portion of the valve. By imparting
a quarter of a revolution to the valve, the communications will obviously be
changed, those pipes previously in communication with the exhaust being
now in communication with the steam from the boiler, and vice versa, the
motion of the engine being thereby reversed. One-eighth of a revolution of
the valve will have the effect of closing all the four orifices or pipes, and of
stopping the engine, as will be clearly understood on referring to the Drawing.
C is a branch steam pipe, communicating with the valve chest and with each
end of the cylinder, the object of this pipe being to effect a more equal and
rapid warming of the cylinder on first starting the engine. Any wear of the
rubbing surfaces of the piston and cylinder may be readily compensated by
simply setting up the conical piston longitudinally inside its slightly conical
cylinder, and this I accomplish by means of the end set screw D (Figures 1
and 3). E, E, are the end covers of the cylinder, serving partly to strengthen
it, and partly to support the main shaft "B. When steam is employed as the

page_text: motive power, I propose to connect the spaces left at each end of the cylinder
between the covers and the ends of the piston by means of two pipes joined
together, and provided with a stop-cock for the purpose of carrying off any
superfluous steam or hot water collected therein.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent is, the general construction,
arrangement, and combination ofapparatus or mechanical parts for obtaining
motive power, as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto
set my hand and seal, this Twenty-ninth day of April, One thousand
eight hundred and sixty-one.
J. HENRY JOHNSON. (L.S.)