IMPROVEMENTS IN STEAM ENGINES AND PROVISIONAL SPECIFICATION
Year: 1860

page_text: LETTERS PATENT to Francis Alton Calvert, of the City of Manchester,
Engineer, for the Invention of "IMPROVEMENTS IN STEAM ENGINES AND
PROVISIONAL SPECIFICATION left by the said Francis Alton Calvert
at the Office of the Commissioners of Patents, with his Petition, on the
14th September 1860.
I, FRANCIS ALTON CALVERT, of the City of Manchester, Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN STEAM
ENGINES AND BOILERS. AND IN VALVES FOR STEAM AND OTHER FLUIDS," to be
as follows:-
The object of my Invention of improvements in steam engines is to
utilise high-pressure steam in the most economical manner, without the
aid of a condenser.
In performing my Invention I admit the steam to the cylinder through
apertures near the end thereof, the said apertures being placed at intervals
nearly round the circumference to equalize the action of the steam on the
piston. Similar apertures in communication with a jacket are placed near
the other end of the cylinder to admit and discharge air.
The steam admission valve consists of a perforated cylindrical shell, working
within a case placed in the steam chest; this case is also perforated, but the
[Price 8d.]

page_text: perforations are so small that by turning the shell three-sixteenths of an
inch, or other small distance, the ports are either opened or closed. The
passages for admitting the steam from the chest to the interior of the shell
are considerably larger than the perforations communicating from the valve
to the cylinder, and by moving the shell until those passages are not in
line with each other, the steam is shut off, and the valve is thus made to
answer as a stop valve. The exhaust valve is made in the following
manner: The lower end of the cylinder is perforated with small holes,
and a sliding plate with corresponding holes is placed above the said end,
by moving the sliding plate until the holes coincide, the valve for the
exhaust is opened, and it is closed by moving the plate until the holes
come over the blank spaces in the end of the cylinder.
The admission and exhaust valves are worked by a rod suspended to
the beam or connected to any other part of the engine; the motion of
the admission valve is regulated by an inclined piece, acted upon by the
governor, thereby giving more or less steam according to the load on the
engine. When the steam is admitted below the piston it impels the piston
to the top of the cylinder, and the air above the piston escapes into the
jacket, and then into the hot well through the upper perforations before
referred to; but when the piston covers the said upper perforations the air
above it becomes compressed and forms a cushion, the reaction of which
and the momentum of the fly-wheel assist in bringing the piston down again
during the descent of the piston; the exhaust valve is opened to allow
the steam and air to escape into the hot well, where it is met by a jet
of water, which is injected by a plunger on the end of the rod for working
the valves, or otherwise. When the piston in its descent arrives at the lower
perforations, the exhaust valve is instantly closed, and the air below the lower
perforations is compressed in the manner before described; when the piston is
down the steam is admitted into the steam chamber, and as soon as the piston
in rising has passed the lower perforations, the steam passing through the
perforations enters the cylinder below the piston, and gives it the requisite
impetus. After the steam has acted on the piston with its full force, it
continues to act by expansion until the entire force of the steam is expended;
and in order to prevent a vacuum being formed below the piston, the
sliding plate of the exhaust valve is lifted off its face, and allows the air from
the hot well to pass through the perforations in the end of the cylinder and in
the sliding plate.. By means of these improvements the piston may be
worked advantageously at a very great velocity, as little motion is given to the
valves, and the passages for the admission and escape of the steam are large.

page_text: I wish to remark that these improved steam engines may be made to
supply and exhaust the steam at both ends of the cylinder, also that the
valves may be applied to other descriptions of steam engines, and to water
and other fluids.
My improved steam boilers are constructed in the following manner :-
Within the outer shell of the boiler is a conical dome; the water surrounds
and covers this dome, and the fire-grate is placed at the lower end thereof.
Under the fire-grate is a box, into which the air is admitted by a damper in
communication with a cylindrical valve; this valve works in a case surrounded
by steam to equalize the expansion. The fire-grate is made in two or more
parts for the purpose of being able to lower one part at a time to remove
clinkers. The boiler is surrounded by a jacket, into which the products of
combustion that are not absorbed by the water surrounding the dome are
conveyed through an aperture above the fire-hole. This jacket communicates
with the chimney through an opening at the bottom; the jacket may be en-
closed in a water chamber. The steam dome is at the top of the boiler, and the
man-hole, when removed, affords access to all parts for cleansing. The water
supply is self-acting, and consists of a float with a hollow rod. The upper end
of this rod is connected to two levers, which are in communication with two
valves similar to the admission valve described in reference to the steam
engine. One of these valves admits steam from the boiler to a cistern, and
the other, when opened, admits water to the boiler from the cistern. When
the water is too low the steam passes up the hollow spindle of the float, and
enters a pipe which is brought near the fire-hole to give notice to the fireman
or engine driver, and the escape of the steam may also sound a whistle.
The main feature of novelty in my improved steam boilers consists in
forming chambers for the accumulation of the rarefied and inflammable
gases, while the openings into the flue are placed at the bottom of such
chambers, and the details given may be considerably modified.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
the said Francis Alton Calvert in the Great Seal Patent Office on
the 13th March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANCIS
ALMON CALVERT, of the City of Manchester, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent,bearing date the Fourteenth day of September,in the year of our Lord

page_text: 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
Francis Alton Calvert, Her special licence that I, the said Francis Alton
Calvert, my executors, administrators, and assigns, or such others as I, the said
Francis Alton Calvert, 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 "IMPROVE
MENTS IN STEAM ENGINES AND BOILERS, AND IN VALVES FOR STEAM AND OTHER
FLUIDS," upon the condition (amongst others) that I, the said Francis Alton
Calvert, my executors or 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 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 Francis Alton Calvert, do hereby
declare the nature of my 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
two Sheets of Drawings, and to the figures and letters marked thereon,
that is to say:--
On Sheet 1, Figure 1 is an elevation of a single-acting steam engine con-
structed according to my improvements; Figure 2 is a sectional elevation
of part of the same; Figure 3 is a plan in section of the cylinder, the steam
admission valve, and part of the hot well; Figure 4 is another section of
the steam admission valve; and Figure 5 is a detached view on an enlarged
scale of the valve motion.
a is the steam cylinder; a', the piston; a2, the piston rod connected to the
cross head a³; a4 is the connecting rod; and a5, the beam, which, in order to
combine strength with lightness,I make with cast-iron ends and centre pieces,
united by wrought-iron tubes; the crank arm a is connected in the usual
manner to the crank shaft a7. At the lower end of the steam cylinder a are
the apertures b, through which the steam enters. These apertures are placed
at intervals nearly round the circumference to equalize the action of the steam
on the piston a¹. Similar apertures, marked c in Figure 6, but not shewn in
Figure 1, are made through the cylinder near the upper end to admit and
discharge air from and into the passage d, which communicates with the

page_text: hot well o; e is a passage or chamber, into which the steam enters previous
to entering the cylinder.
The steam admission valve consists of a perforated cylindrical shell f
working within a case g, placed in the steam chest h; the case g is provided
with perforations corresponding to those in the shell f, and these perforations
are all so small that by turning the shell three-sixteenths of an inch, or other
small distance, the ports for the passage of the steam are either opened or
closed. i, i, are the openings for admitting the steam from the chest h to the
interior of the shell f; these openings are considerably larger than the per-
forations communicating from the valve to the passage or chamber e.
The mode of constructing the exhaust valve is as follows:-The lower end
or lid of the cylinder marked jis perforated with small holes, as shewn best in
Figures 2 and 3, and the sliding plate k, having corresponding holes, is placed:
above the end; the sliding plate k is moved to and fro, so as to open and
close the perforations in the end j, by means of the tappet 7 on one of the
rods ; these rods are connected to the crosshead a³. The tappet / acts
alternately on the upper and lower arms. of the double lever m, which is
fixed to the rocking shaft m¹; to this shaft is fixed the lever m², the lower end
of which passes through a slot in a rod attached to the under side of the
sliding plate . To one of the rods is also fixed the tappet 12 for working
the steam admission valvef; at one end of this valve is the spindle f¹, to
which is fixed the lever f2; to this lever is jointed the lower end of the link f³,
the upper end of which is hinged to a stud passing through a slot in the
weighted lever /4, to which is attached the plate f5, on which the tappet 12
acts to open the valve f; the valve is closed or the steam cut off by the same
tappet 2 acting on the adjustable piece f6, which is fixed to the lever f4 by a
set screw; this piece can be moved to suit the quantity of steam required.
The position of the link f³, and consequently the position of the stud to which
it is hinged in the slot leverf, is varied by means of the governorshewn at n,
in Figure 1; the spindle n' of the governor acts on the elbow lever n², to the
upper arm of which is jointed one end of the link n³, the other end being
connected to the link f³. When the governor balls are down, as shewn in
the Drawing, the valve will be ready to give the greatest amount of steam to
the cylinder; but when the balls expand the stud of the link f³ approaches
the fulcrum of the lever f4, and consequently the traverse of the valve is
reduced, thereby admitting less steam. The framing of the beam, the pedestal
of the crank shaft, and the steam cylinder, are all supported by the chamber o,
which forms the hot well, the water from which is injected towards the lower
end of the cylinder a,.when the exhaust valve is open by the plungers pat the
Z2

page_text: ends of the rods 11; these plungers work in the barrels p¹, shewn best in
Figure 2; the water from both the barrels punite in a centre pipe p2, which
is furnished above with a perforated top or rose p³. Under the pipe p² is a
flat valve, through which the water enters from the hot well to supply the
plungers with a fresh charge of water at each stroke; by this means the
plungers are always supplied with the coldest water in the hot well to meet
the exhaust, thereby assisting condensation.
The Drawing, Figure 1, represents the parts in the positions they occupy
when the engine is at half stroke, and the mode of operation is as follows:-
The piston is now supposed to be ascending, the steam having been admitted
below the piston and cutoff, is now impelling the piston upwards by its elastic
force, and the air above the piston is escaping through the upper apertures c
and passage d into the hot well o, but when the top of the piston has passed
beyond the said apertures, the air in the space above them becomes compressed
(between the piston and the cylinder lid), and forms a spring cushion, the
reaction of which when the crank has turned over the centre, and the
momentum of the fly wheel, bring the piston down again. When the piston is
at the top of the cylinder the tappet, acting on the leverm, opens the exhaust
valve, which remains open during the descent of the piston, to allow the
steam and air under the piston to escape into the hot well, where it is met by
the water injected through the rose p³, as above described; the exhaust valve
remains open until the lower part of the piston has about half covered the
apertures b, when the tappet l, acting on the lower arm of the lever m, moves
the plate k, and closes the valve; as soon as the piston covers the apertures b,
the air between the lower part of the piston and the bottom of the cylinder
becomes compressed, and forms an elastic cushion, the action of which assists
in moving the piston upwards. When the piston in descending has closed the
apertures b, the tappet 12, acting on the plate f³, opens the ports of the steam
admission valve f, to admit the steam into the passage or chamber e, and as
soon as the crank has turned over the centre, and the piston in rising uncovers
the apertures 6, the steam rushes into the cylinder through the said apertures,
and impels the piston upwards with the full force of the steam; when the
piston has been raised through the space between the plate f5 and the tappet/²,
the said tappet acts on the piece fo, and closes the admission valve, thereby
cutting off the steam, which then acts expansively until the entire force is
expended. In order to prevent a vacuum being formed below the piston, the
sliding plate of the exhaust valve is loose on the end j, and it is capable of
being lifted off its face for about an eighth of an inch, to allow air from the
hot well to pass into the cylinder through the perforations of the exhaust valve.

page_text: E
When it is requisite to stop the engine the attendant draws back the the
plate f by means of the handle f7, until the tappet 72 can pass without
influencing the weighted lever f. In starting the engine the plate f³ is
brought back to its original position, care being taken that the tappet 12 is
above the plate at the time.
By means of these improvements the full expansive force of the steam can
be utilised; steam at a high pressure can be advantageously used, and the
velocity of the piston may be greatly increased, owing to the moist condition
of the cylinder, caused by the piston taking in and discharging air from the
hot well to the upper part of the cylinder at each stroke; also by the piston
forming a vacuum when the steam has expanded it to its full extent.
I wish to remark that the valves above described may be applied to
steam engines of the present construction, and in other cases as a steam
valve. Figure 6 is a section of part of a double acting steam engine con-
structed according to my improvements; in this case the cylinder is placed
horizontally, and the exhaust valves k are in communication with the hot
well by means of the passages q.
On Sheet 2, Figure 7 is an elevation of the outside, and Figure 8,a sectional
elevation of my improved steam boiler; and Figure 9 is a plan of the same.
A is a conical dome with a hemispherical top; this dome is placed above the
fire grate B, which is supported at the upper part of the ash-pit C,into which
air is admitted by the damper 1); the fire grate B is made in two parts, which
are hinged to the ash-pit C; each part can be lowered independently of the
other by the eccentrics B', for the purpose of removing clinkers; the dome A
is surrounded by the cylindrical shell E, the space between the two being
filled with water; Fis the casing around the shell E, into which the products
of combustion enter from the dome A, and G is the outer casing of the boiler,
the upper portion of which forms the steam chamber; the fuel is supplied to
the fire grate B through the door H, and passage I, the products of com-
bustion after rising in the dome A, where the greater portion of them are
absorbed by the water surrounding it, are conveyed through the passage I into
the hot air chamber between the shell E and casing F, where they again rise
and give off their heat into the surrounding water, while the draught is con-
tinued forward uninterruptedly around each side, and at the bottom of the
hot air chamber and of the water jacket, through the flue J to the chimney.
From the foregoing description and Drawing it will be seen that the dome
A, and the space between the shell E and casing F, form chambers for the
accumulation of rarefied air and inflammable gases, which chambers are entirely
surrounded by water, by which the heat is absorbed, while the opening.into

page_text: the flue is placed at the lowest possible level, in order that the heavier gases
may be carried readily forward to the chimney.
The mode of feeding the boiler with water is as follows:-K is a cistern
which is in communication with the boiler by means of the two pipesL and M,
the former opening into the steam chamber, and the latter into the water;
the valves L' and M' are very similar to the steam admission valve described
in reference to the steam engine; the valves L¹ and M₁ are connected so as to
act simultaneously by the rod N, which is jointed to the lever N1; this lever
vibrates on the fulcrum N2, and its other extremity enters between two
adjustable fingers fixed to the rod O of the float 01. The rod O is hollow and
passes through the cylinder O2 fixed on the boer; the hollow rod O has a
small hole through it, at that part where it works through the cylinder O2,
and on the top of the rod is a steam whistle. When the water in the boiler
descends to the desired level, the float O' descends also, and the upper finger
of the rod O,acting on the lever N¹,opens the valves L' and M', the former of
which admits steam from the boiler above the water in the cistern K, while
the latter allows the water in the cistern to be forced into the boiler through
the pipe M, as soon as the level of the water in the boiler is raised sufficiently;
the float O¹ in rising closes the valves L' and M¹,and the steam which is thus
shut in the cistern, on becoming condensed, forms a partial vacuum, which
raises the water from the hot well of the engine or from any convenient tank
or reservoir, which is in communication with the cistern through the pipe K¹.
In case of the non-supply of water to the boiler, the float01, descendingbelowits
proper level, then brings the hole in the pipeObelow the end of the cylinderO2,
thereby allowing steam to pass through the rod O to the whistle. The
requisite quantity of air for supporting combustion is admitted to the ash-pit
C thro' the damper D in the following manner:-The cylindrical valve P
working in the case F¹ is acted upon by the steam in the boiler, and the case
P1 is surrounded by steam to equalise the expansion of the parts; the valve P
is connected to the damper D by the rod D¹; when the steam is at its proper
pressure the damper is held open to the requisite extent for admitting as
much air as is necessary for combustion, but if the pressure of steam increases
beyond its proper limit, the valve P in rising closes the damper D, and reduces
the quantity of air admitted to the fire or shuts it off entirely; the contrary
action takes place when the pressure of steam is reduced. It is evident that
the boiler must be provided with the ordinary man-hole safety valve, and the
usual apparatus to render it complete. The feed apparatus above described
is applicable to boilers of the ordinary construction. This improved steam
boiler when properly used is capable of rendering available the whole heat of

page_text: the fuel employed; the boiler is also lighter, cheaper, stronger, easier to
clean, and less liable to corrode than boilers of the ordinary construction,
and it is peculiarly adapted for heating purposes on account of the sim-
plicity of its construction and automatic arrangements.
Having thus described the nature and particulars of my improvements
in steam engines and boilers, and in valves for steam and other fluids, I
wish it to be understood that I do notclaim any of the well-known parts, which
are shewn and referred to for the purpose of illustrating my Invention;
but I declare that I claim the various improvements herein-before described
and shewn in the Drawings.
In witness whereof, I, the said Francis Alton Calvert, have hereunto
set my hand and seal, this Second day of January, in the year of
our Lord One thousand eight hundred and sixty-one.
F. A. CALVERT. (L.S.)