IMPROVEMENTS IN OSCILLATING STEAM. : ENGINES. A communication
Year: 1855

page_text: LETTERS PATENT TO
Avery, or 32, Essex Street, Strand, London,,
Patent Agent, for the Invention of "IMPROVEMENTS IN OSCILLATING STEAM.
: ENGINES. A communication."
PROVISIONAL SPECIFICATION left by the said John Avery at the Office
of the Commissioners of Patents, with his Petition, on the 13th June
1855.
I, JOHN AVERY, of 32, Essex Street, Strand, London, Patent Agent, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
OSCILLATING STEAM ENGINES," a communication, to be as follows; and con-
sists in an improved method of cutting off the steam from the cylinders
of oscillating engines, at such point in the stroke as may be desired for
employing the expansive force of the steam to complete the stroke ;* also in
an improved valve-for stopping, starting, reversing, and, if desired, also govern-
ing, either a single or double; engine; and also in constructing or applying the
steam pipes or passages, which connects the pillow blocks of the trunion bear-
ings, which in this case also serve as steam chests, so that a proper provision is
made for the lateral expansion of the cylinders and other working parts of the
engine by causing the framing to expand in the same ratio.

page_text: A bed plate is provided to support all the working parts of the engine, in
which are placed pillow blocks, containing the bearings for the solid cylinder
trunions, and serve at the same time as steam chests and stationary induction
& eduction valves to supply the cylinders with steam at opposite points at
the same time by their own oscillation.
There is in the steam chambers a partition dividing the induction and
eduction chambers, which chambers are extended to such a length as to bring
the stationery valves near the ends of the steam cylinders, so that the ports of
the chambers may communicate with ports which lead from the valve seats
outside the cylinder without any passages leading along the sides of the
cylinder, and by the extension of the chambers and shortening of the passages
a saving of steam is effected at every stroke of the piston. There are two cut-
off valves, each in the form of a ring, the full size of the cylinder, one being
fitted to each end of the cylinder, having two stems working through the
cylinder head. These valves are made slightly conical externally to enter cor-
responding seats. When in these seats the valves close the ports. The valves
are actuated to cut off the steam by the following means:-Opposite the ends
of the cylinders there are two transverse shafts supported in fixed bearings.
These shafts each carry double arms or bars, one opposite to each valve rod;
and also carry levers, which are connected by rods with opposite arms of a
lever, so that when the shaft at the end of the cylinder is moved to give the
arms of the lever an inclined position, the other shaft moves simultaneously, to
give its arms a corresponding inclination in an opposite direction. At a certain
point in the stroke of either piston the oscillation of the cylinder brings the
stems of the cut-off valve belonging to that end of the cylinder which is
receiving steam into contact with the inclined faces of the corresponding arms,
-and-thie continuous-movement of the cylinder causes the-valve which has up-to
this time been confined in the cavity in the cylinder head by the pressure of
the steam on its face to be moved to close the ports. It is not necessary that
the valve shall be moved the whole distance necessary to close the ports, but
will be sufficient to move it only so far as to allow the steam-to-get-behind-it.
As soon as the steam gets behind it the valve is balanced by the equal pres-
sure of the steam on all sides of it, but the steam following the piston assumes
the character of a current, and by this action the valve when it is properly
balanced will be caused to follow the piston and close the ports. As soon as
the crank passes the centre, the valve will be instantaneously opened again by
the pressure caused by the commencement of the return movement of the
piston, and a full opening of the ports for a free exhaust will be immediately

page_text: obtained. The time of cutting off the steam is varied by varying the inclina-
tion of the arms, a greater inclination causing the cutting off to take place
earlier in the stroke, and a less inclinature to take place later. By bringing
the arms perpendicular to the central positions of the cylinder they will be
inoperative, as the valve stems will work clear of them, and the induction of
steam to the cylinder will continue through the whole of the stroke.
The valve by which the engine is started, stopped, and reversed, and has its
speed governed, consists of a hollow cylinder, with a partition dividing it into
two chambers, the former of which may be termed the induction and the latter
the eduction chamber. The induction chamber has a slotted opening through
the periphery of the cylinder, and the eduction a similar opening opposite; both
openings lead into a chamber in a fixed casing, which surrounds the valve,
liaving on it the induction and eduction pipes. The valve is arranged concen-
trically to the cylinder trunions, and short projections, serving as journals,
are made on either end to enter corresponding cavities or bearings in the
contiguous faces of the pillow blocks, the ends of the valve being faced to
fit steam-tight, between the faces of the pillow blocks. In the ends of the valve
there are two ports opposite to each other, communicating with the induction
chamber, and two other ports, also opposite each other, communicating with
the eduction chamber, the ports being as close as possible to the partition, and
being diametrically opposite. Those faces of the pillow blocks between which
the valve works are each provided with four parts, viz., two leading into the
upper chamber of the steam chest, and two leading to the lower chamber of
the same.
The ports are diametrically opposite each other, so as to bring one
of the chambers or passages into communication with the induction chamber,
and the other passage into communication with the eduction chamber; and by
a proper movement of the valve from one passage to the other the action of
the steam is reversed, and hence the direction of revolution of the engine.
By bringing the ports of the valve opposite the spaces in the casing, the
induction and eduction of steam is caused to cease altogether, and the engine
is stopped. The valve also serves as a throttle valve, and may have a governor
applied to its lever. The valve operates alike on both steam cylinders, and
a valve of similar construction with one end closed would operate in the
same manner upon a single-cylinder engine.
. There are pipes or passages cast in the bed plate of the engine to connect
the lower-chambers-in the pillow blocks or steam chests with the correspond-
ing chambers of the pillow blocks, to convey the steam from the former to the
latter to supply the steam to the cylinder on opposite sides at the same time.

page_text: These pipes or passages serve as expanding braces to the bed plate, expanding
by the heat of the steam in the same degree as the cylinders, and therefore
preserving tight-working joints between the valves on the steam chests and
the valve seats on the cylinders. There is also a strong pipe or casting con-
taining passages, to connect the upper chambers of the pillow blocks or steam
chests, serving as an expanding brace to the upper parts of the pillow blocks or
steam chests, and producing a similar effect on the pipes or passages below.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Avery in the Great Seal Patent Office, on the 11th
December 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
AVERY, of 32, Essex Street; Strand, London, Patent Agent; send greeting.
WHEREAS Her most,Excellent Majesty. Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of June, in the year of our Lord,
One thousand eight hundred and fifty-five, in the eighteenth year, of Her.
reign, did, for Herself, Her heirs and, successors, give and grant unto me,i
the said John Avery, Her special licence that I, the said John Avery, my
executors, administrators, and assigns, or such, others as I, the. said John.
Avery, 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 termi
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 OSCILLATING.
STEAM ENGINES," (a communication,) upon the condition (amongst others) that
1, the said John Avery, by an instrument in writing under my hand and seal,
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 Avery, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, that is to say:
This Invention relates to certain improvements on a. former Patent for

page_text: oscillating engines, dated 5th March 1855, granted to Auguste Edouard Lora-
doux Bellford, as a communication from the same Inventor; and consists,-
Firstly, in a simple and effective method of cutting off the steam from the
cylinders of oscillating engines at such point in the stroke as may be desired
for the purpose of employing the expansive force of the steam to complete the
stroke..
Secondly, in an improved valve for stopping, starting, reversing, and, if
desired, also governing, either a single or double engine.
Thirdly, in constructing or applying the steam pipes or passages which
connect the pillow blocks of the trunnion bearings, which in this case also
serve as steam chests, so that a proper provision is made for the lateral
expansion of the cylinders and other working parts of the engine, by causing
the framing of the engine to expand always in about the same ratio with the
cylinders and working parts.
"
:
i
The accompanying Drawings represent a double horizontal oscillating
engine, which exhibits the three features of the Invention.
'
Fig. 1 is a vertical section, taken directly through the centre of one of the
cylinders..
Fig. 2, a transverse vertical section, directly, through the cylinder trunnions
and the induction and eduction pipes.
Fig. 3, a central longitudinal section of one of the 'cylinders, in a plane
passing through its axis of oscillation, showing also sections of the steam chests
and trunnion bearings.
Fig. 4 is a side view of one of the cylinders, showing the arrangement of
the ports.
:
Fig. 5 represents one of the pillow blocks, which contain the trunnion
bearings, and also serve as steam chests and induction and eduction valves, the
side here shown being that next the cylinder.
Fig. 6 is an opposite side view of the pillow block.
Fig. 7 is a transverse section, in the line *,, of Fig. 2, of the valve, by
which the starting, stopping, reversing, and governing the engine are effected.;
Fig. 8 is an end view of the same.
t
Fig. 9 represents one of the cut-off valves detached from the engine.
Similar letters of reference indicate corresponding parts in the several Figures.
A is the bed. plate_or_frame, which supports_all_the_working parts of the
engine; B, B, B',.B, are the pillow blocks which contain the bearings a for
the solid cylinder. trunnions a; a, and serve at the same time as steam chests
and stationary induction and eduction-valves to supply the cylinders.C, C; with

page_text: steam at opposite points at the same time by their own oscillating movement.
The internal. construction of the steam chests is shown by the dotted lines; in
Fig. 5; where b, b, represents a partition between the steam chambers c and d, of
which one is an induction chamber and the other an eduction chamber, which
are extended to such a length as to bring the stationary valves e, e, near the ends
of the steam cylinders, so that the ports f, f, and g, g, of the chambers c.and d
may communicate with ports h, h, which lead from the valve- seats outside the
cylinder directly into the cylinder, as shown in Fig. 3, without any passages
leading along the sides of the cylinder. By this extension of the induction and
eduction chambers and shortening of the passages in the cylinder, a saving of
steam is effected at every stroke of the piston. D, D', are the cut-off valves,
each in the form of a ring of the full size of the cylinder, one being fitted to
each end of the cylinder, and having two stems i, i, working. through the
cylinder head. The valves are made slightly conical externally to enter
corresponding seats, which are produced by a slight conical enlargement of the
ends of the cylinder; when in these seats the valves close the ports. Each
cylinder head has an annular cavity inside it to receive the valves when they
are open, as shown in Fig. 3. The valves are actuated to cut off the steam
by the following means:-Opposite the ends of the cylinders there are two
transverse shafts E, E', supported in fixed bearings G, G, in positions opposite
the centres of the cylinders. These shafts each carry double arms or bars j or
j', one opposite to each valve rod i. The two shafts carry levers K, K', which
are connected by rods 1, 1, with opposite arms of a lever m, so that when the
shaft E is moved, by the engineer applying his hand to the lever 1 to give the
arms j.j, an inclined position, the shaft E¹ moves simultaneously with E, to
give the arms j', j', a corresponding inclination in an opposite direction. This
is illustrated in, Eig. 1, where the arms j, j, and j, j, are shown at corre-
-sponding-inclinations-in-opposite-directions. At a certain point in the stroke
of either piston, the oscillation of the cylinder brings the stems of the cut-off
valve belonging to that end of the cylinder which is receiving steam, into
contact with the inclined faces of the corresponding arms j, j, or j',, and the
continuous movement of the cylinder causes the valve, which has up to this
time been confined in the cavity in the cylinder head, by the pressure of the
steam on its face, to be moved to close the ports h, h.. It is not, however,
necessary that the valve shall be moved the whole distance necessary to close
the ports, but will be sufficient to move it only so far as to allow the steam to
get behind it. As soon as the steam gets behind it, the valve is balanced by
the equal pressure of the steam on all sides of it, but the steam following the

page_text: piston assumes the character of a current, and, by the action of this current,
the valve when it is once properly balanced will be caused to follow the piston
and close the ports h, h. As. soon as the crank passes the centre, the valve
will be instantaneously opened again, by the pressure caused by the commence-
ment of the return movement of the piston, and a full opening of the ports for
a free exhaust will be immediately obtained. The cut-off valves are balanced
laterally by the induction and eduction of steam on opposite sides of the
cylinders at the same time. The action of the cut-off valves is illustrated in
Fig. 1, where the valve D is represented as having been just started to cut off
by its stems coming in contact with the arms j, j, of the shaft E. The time.
of cutting off the steam is varied by varying the inclination of the arms j, j,
and j, j, a greater inclination causing the cutting off to take place earlier
in the stroke, and a less inclination to take place later. By bringing the
arms perpendicular to the central position of the cylinders, as shown by the.
dotted outlines in Fig. 1, they will be rendered inoperative, as the valve stems
will work clear of them, and the induction of steam to the cylinder will
continue through the whole of the stroke.
F, Figs. 2, 3, 7, and 8, in the valve by which the engine is started, stopped,
and reversed, and has its speed governed. This valve consists of a hollow
cylinder, with a partition n, dividing it into two chambers o, o'; the former of
which may be termed the induction chamber, and the latter the eduction
chamber. The induction chamber has a slotted opening p through the
periphery of the cylinder, and the eduction chamber a similar opening p²,
opposite to p, as shown in Figs. 2 and 7; the opening p leading into a
chamber s, and, the opening p¹ into a chamber s¹ in a fixed casing H, which
surrounds the valve, the said chamber s, receiving the induction pipe t, and
the chamber s the eduction pipe t¹. The valve F is arranged concentrically
to the cylinder trunnions, and short projections u; u, serving as journals, are
made on either end to enter corresponding cavities or bearings in the con-
tiguous faces of the pillow blocks B, B', as shewn in Figs. 2 and 3, the ends
of the valve being faced to fit steam-tight between the faces of the pillow
blocks. In the ends of the valve there are two ports q, q', opposite to each
other, communicating with the induction chamber o, and two other ports q¹
also opposite each other, communicating with the eduction chamber o; the
said ports being as close as possible to the partition N, and the ports q' being
diametrically opposite those q, as shown in Figs. 7 and 8. Those faces of the
pillow blocks B, B, between, which the-valve works, are each provided with
four ports, viz., two leading into the upper chamber cof the steam-

page_text: chest, and two 71, 7, leading to the lower chamber d of the same. The
ports and are diametrically opposite each other, so that the port.q of
the valve may stand opposite the port r, while the port q¹ stands opposite.the
port; so as to bring the chamber c into communication: with the induction
chamber of the valve, and the chamber d into communication with the
eduction chamber o¹; or, by a proper movement of the valve, to bring the port q
opposite the port, and the port q' opposite the port, to bring the chamber
d into communication with the induction chamber o' of the valve, and the
chamber c with the eduction chamber o¹, and thus reverse the action, of the
steam, and hence the direction of revolution of the engine. By bringing
the ports q, q', the one opposite the space between the ports and r¹, and. the
other opposite the space between the ports and, the induction and
eduction of steam is caused to cease altogether, and the engine of course is
stopped. The valve F also serves as a throttle valve, and may have a governor
applied to its lever v. It will be understood that it operates alike on both
steam cylinders, and that a valve of similar construction, with the exception
that it would have one end closed, would operate in the same manner upon a
single cylinder engine.
.
I, I, are pipes or passages cast in the bed plate of the engine to connect
'the lower chambers d, d, in the pillow blocks or steam chests B', B', with 'the
corresponding chambers of the pillow blocks B, B, to convey the steam from
the former to the latter to supply the steam to the cylinder on opposite sides
at the same time. These pipes or passages serve as expanding braces to the
bed plate, expanding by the heat of the steam. in the same degree as the
cylinders expand, and, therefore preserving tight-working joints between
the valves on the steam chests and the valve seats on the cylinders:
J; J, is a strong pipe or casting, containing passages to connect the upper
chambers c, c, of the pillow blocks or steam chests, and producing a similar
effect on the pipes or passages I, I, below.
Having thus fully described the particulars and nature of the said Invention,
and the manner in which the same is or may be carried into effect, I wish it
to be understood that what I claim is,-
First, the cutting off of the steam at such point as may be desired in the
stroke of the piston by means of ring valves D, D¹, fitted in the ends of the
cylinders and furnished with protruding stems i, i, which are to be acted upon
for the purpose of moving or starting the valve, substantially as herein described,
by arms or bars j, j', or their equivalents, occupying an inclined position out-
side the cylinder; or by valves applied on any equivalent mariner, that is to

page_text: say, between the main induction and eduction valve and the cylinder, in such
a way that when balanced by the admission of steam behind them they will be.
closed by the current of steam following the piston, and opened by the back
pressure before the piston.
Second, the double-chambered cylinder valve F, applied, as herein described,
to work within a casing H, which contains one chamber s communicating
with the induction pipe, and another s¹ communicating with the eduction pipe,
and to operate in connection with the within-described arrangement of ports
in the double-chambered steam chests B¹, B', for the purpose of starting,
stopping, reversing, and governing the speed of the engine.
Third, constructing or applying the steam pipes or passages, which form the
connections between the upper and lower chambers of the steam chests B
and B', in such a manner as to serve as expanding braces to the bed plate or
frame of the engine, whereby tight working joints are preserved under all
variations in the expansion of the cylinders or other working parts of the
engine, substantially as herein set forth.
In witness whereof, I, the said John Avery, have hereunto set my hand
and seal, this Tenth day of December, in the year of our Lord One
thousand eight hundred and fifty-five.
JOHN AVERI. (L.S.)