IMPROVEMENTS IN STEAM ENGINES
Year: 1856

page_text: LETTERS PATENT to James Gray Lawrie, of Glasgow, for the Invention of
"IMPROVEMENTS IN STEAM ENGINES."
PROVISIONAL SPECIFICATION left by the said James Gray Lawrie at
the Office of the Commissioners of Patents, with his Petition, on the
8th May 1856.
I, JAMES GRAY LAWRIE, of Glasgow, do hereby declare the nature of the
Invention for "IMPROVEMENTS IN STEAM ENGINES," to be as follows:-
This Invention partly consists in working the expansion valves of steam
engines by means of links, rods, or levers, connecting the same with reciprocating
parts of the engine, such as the side levers of the air pump.
The Invention also consists in so connecting the expansion valves with re-
ciprocating parts of the engine, or with links, rods, levers, or other instruments
used for the purpose of working the valves, that the extent of motion or stroke
of the expansion valve may be varied as required; and this may be done by the
use of a grooved course on the link, rod, lever, or other instrument from which
the motion is taken, in which grooved course the part of the machinery which
communicates the motion to the valve slides, so as to effect an increase or dimi-
nution of the extent of motion communicated to the valve.
The Invention also consists in giving motion to expansion valves (when such
valves are used) in connection with engines in which the cylinders are placed
above the level of the crank shaft, by means of a stem, which passes through
the opposite end of the valve box to that through which the stem of the
ordinary valve passes.

page_text: The Invention also consists in admitting steam to both the cylinders of a
pair of engines by means of a single valve, perforated with suitable passages,
and revolving on an axis continually in one direction; also in mounting.
revolving conical valves used for admitting steam to the cylinders of steam
engines on axes, which axes are set up by screws or otherwise, so as to adjust
the friction of the valve on its seat.
SPECIFICATION in pursuance of the conditions of the Letters Patent; filed.
by the said James Gray Lawrie in the Great Seal Patent Office on the
6th November 1856.
1
TO ALL TO WHOM THESE PRESENTS SHALL COME; I, JAMES
GRAY LAWRIE, of Glasgow, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her, Letters
Patent, bearing date the Eighth day of May, in the year of our Lord One
thousand eight bundred and fifty-six, in the nineteenth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said James
Gray Lawrie, Her. special licence that I, the said James Gray Lawrie, my
executors, administrators, and assigns, or such others as I, the said James
Gray Lawrie, 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,
upon the condition (amongst others) that I, the said James Gray Lawrie, my
executors or administrators, by an instrument in writing under my, or their,
or one of their bands and seals, should particularly describe and ascertain, the
nature of the said Invention, and in what manner the same was to be per
formed, 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 James Gray Lawrie 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 thereof, that is to say:
The first part of my Invention relates to working the expansion valves of
steam engines by means of links, rods, or levers, connecting the same with
reciprocating parts of the engines, such as the side levers of the air pump, and

page_text: in so connecting the expansion valves with reciprocating parts of the engine, or
with links, rods, levers, or other instruments used: for the purpose of working
the valves, that the extent of motion or stroke of the expansion valve may 'be
varied, as required.
1,3.
The Drawing annexed-shows the application' of this part of my Invention to
a form of engines in which there are two steam cylinders placed over the crank
shaft, and which is a very usual form of engine applied to work, the screw
propeller 'of steam vessels...
Figures 1, 2, 4, 9, 10, 11, Sheet 1, show one mode in which this part of my
Invention may be carried out; Figures 3, 5, 7 show another. way; and
Figures 6 and 8 show a third-arrangement for the same purpose."
In Figures. 1, 2, 4, 9, 10, 11, A, A, are the steam cylinders; B, the levers,
which work the air pumps; C, the crank shaft'; G, the valve, applied to.
regulate both the induction and eduction of the steam; H, the expansion valve;
or 'the valve applied to regulate the 'admission of the steam to the valve. G
when working the steam expansively, 'and so on. The valve G is so constructed;
that in its action or motion all the steam which obtains access to the steam
cylinders must pass through the ports or passages G, G¹, and the valve H
during its action, by 'covering or closing those ports G¹, G¹, at the proper times;
excludes the steam from the steam cylinder during the portions of the stroke,
which are to be performed by the expansive action of the steam. The valve G
receives its action from one or more excentrics as usual by means of link
motions or 'otherwise, and the valve H receives its motion as follows:-The
stems H of the valves 'H are "carried upwards through the casing cover, and
are connected by means of the shafts D¹ and the levers E, E, with the rod K,
which rod, by means of the arc or link U, attached to the lever B, receives
motion from the lever B. The rod K at the bottom end is split or forked, and
embraces within the fork the arc or link U, as shown in Figure 11. The
slide block' U', shown in Figure 11, which works in or traverses the grooved
course or oblong opening in the link or arc U, carries a pin L, which pin L has
on it two excentrics L, L, and a worm wheel M, into which the worm N.gears
or works, and this worm N, by means of the spindle or handle N, which is
capable of a rotary motion, affords the means of placing the eccentricity of the
excentrics Labove or below the centre of the pin L. The spindle or handle N¹³;
besides being capable of a rotary motion, can be pulled or pushed in the direc
tion of its length, so that by its means the 'block U₁ can be traversed in the
grooved course or oblong opening of the link or are U, in order that the
rod K may receive a motion corresponding with that of certain different.parts
of the levers B. With this arrangement and connection of parts, means are
+

page_text: provided by which the steam can be excluded from the steam cylinders during
certain parts or portions of the stroke of the piston; and the following are the
relative principal dimensions, such as I use in my own practice, in the con-
struction of such machinery :-
Length of stroke of valve G = 1; cover on steam side =
=
cover on
eduction side = 0; advance of excentrics for valve G=1; width of ports
G, G', distance over the ports G', G', measuring on the back of the
valve G, that is, from the point G2 to the point G2, shewn on Figure 2 = a
length which may be represented by d, and which may be taken equal to
about 2 length of extreme stroke of valve H=1; total breadth of
valve II, that is, from H to H = distance d, minus, or in the case when
d=2, the breadth from H' to H2 minus = 1; width of
port (measuring in the direction from H₁ to H¹), which is a port through
the centre of the valve, Hd, minus 1, when dis made =
23;
excentricity of excentrics L', L' = ; length of lever E = length of lever E';
length of rod K, that is, from the point K, being the centre of the pin
through the end of the lever E to the centre of the pin L; when the excen-
tricity of the excentrics L, L', is placed below, the pin L is made so as to have
the portions of the up stroke and down stroke of the piston, during which the,
steam is admitted to the cylinder, nearly equal.
The link or arc U is of such dimensions, and so placed on the levers B; as
shown on the Drawing, that the valve H may receive a stroke equal in length
to that of the valve G, or may have little or no stroke or motion at all, if the
centre of the pin L be placed coincident or nearly so with the centre upon or.
about which the lever B vibrates or oscillates. When the valve H is worked
with a stroke equal in length to that of the valve G, the steam cylinder receives
steam for a considerable length or portion of the stroke, and if the stroke be
reduced, by the slide Ubeing traversed along the arc U, so as to be nearer
the centre about which the lever B vibrates, the steam is admitted to the steam
cylinder for a less portion of the stroke, depending upon the position which the
block U occupies in the oblong opening of the arc U. If it be desired to
have the valve H out of gear altogether, that is, to have it so that it does not
exclude the steam from the cylinder during any portion of the stroke, that can
be done by placing the centre of the pin L as nearly as possible coincident with
the centre about which the lever B vibrates, and by placing the excentricity of
the excentrics L, L', above the pin L.
In Figures 3, 5, 7, which show another mode of accomplishing the same
object, the letters A, B, C, D, E, E, F, G, G, G, H, H1, H2, represent the same
parts as before. D) is a shaft; which may be called a wypur shaft, carrying

page_text: three levers K, K³, K³, of which K³, K³, carry each at their outer end levers
or rods K', K', each valve II having one lever K³ and one rod K¹; K, K, are
rods, one for each valve H, connecting a pin in the lever B with one end of
the link or arc U, which link or are U is carried at the other end by the upper
end of the rod or lever K'. Each rod or lever K¹ is provided with a rod and
handle N2, which, by being pushed or pulled in the direction of its length,
affords the means of traversing the arc or link U upon the pin in the outer end
of the lever E', and in that way the action or motion of different parts of the
link U can be imparted to the valve H. Similarly in this arrangement, to that
adopted in the former, if it be desired to put the valve H out of operation, that
is, to put it so as not to exclude the steam from the cylinder during any portion
of the stroke, the link or are is traversed so as to place that part of the oblong
opening which is opposite the upper end of the rod K¹ on the pin in the outer
end of the lever E¹, and at the same time, by means of the levers K, K³, the
rod K' is raised and the valve H depressed by the amount, about of the unit,
adopted in the scale of principal dimensions already given.
The link or arc U is of such dimensions, and so placed, that by means of the
pin in the lever B the valve H may receive a stroke equal in length to that of
the valve G, when the pin in the outer end of the lever E' is in gear with the
end of the link U at the rod K, or the valve may have little or no stroke
ór motion at all if that pin in the outer end of the lever E¹ be in gear with the
end of the link or are U at the rod K¹. When the valve H is worked with a
stroke equal in length to that of the valve G, the steam cylinder receives steam
for a considerable length or portion of the stroke; and if the stroke be reduced,
by traversing the link or are U the steam is admitted for a less portion of the
stroke, depending upon the position which the pin in the end of the lever E¹
occupies in the oblong opening of the arc U.
In Figures 6 and 8, which show the method in which the principle of
raising or lowering the expansion valve to throw it out of action, may be
applied to expansion valves worked by a link motion, as described in the
Specification of a Patent granted to me, and dated the Nineteenth July, One
thousand eight hundred and fifty-five. The letters A, C, G, G', G², II, H¹, H³,
represent the same parts as before. I, I, are excentrics and rods, to which
are attached one end of the arcs U; 1' are rods to which the other end of the
links U are attached, and these rods I' (one being for each valve H) are
carried by the outer ends of the levers K³, which levers K, K³, together with
the levers 1, are upon a wyper or weigh shaft D, and which afford means
similarly to the arrangement in Figure 5, by which the valve H can be

page_text: lowered of the unit, adopted in the following scale of parts, when it is desired,
to put the valve; H out, of, operation.
.In, this arrangement; of; parts the following are, the relative principal,
dimensions such as I use in my own practice:
Length of, stroke of valve G=1; cover on steam. side=14;, cover on,
eduction side=0; advance of, excentrics for valve G1; width of ports.
GG, distance over, the ports G, G', length of stroke of valve H; total
breadth,of, valve II, and width of port Hs through the valve H, the same as
in, the, arrangements already explained, and shown in the other Figures;
length of rods I, I', what is necessary in order that the valve H may exclude.
the steam, from, the steam cylinder, about equally in the up and down strokes:
of the piston; the centre of the excentrics I, I, and the centre of the crank
pin of the engine or steam cylinder, to which each excentric I belongs, to be,
in, a straight line with the centre of the crank shaft, and on opposite or dif-
ferent sides of the centre of that shaft; the link or are U is of such dimensions,
and so placed, that by means of the excentric. I the valve H may receive a
stroke equal in length to that, of the valve G when the end of the arc U at the
rod I is in gear with the valve, and may have little or no stroke or motion at
all if the end of the arc U at the rod I is in gear with the valves. When
the valve His worked with a stroke equal in length to that of the valve G,
the, steam cylinder receives steam for a considerable, length or portion of the
stroke, and if the stroke be reduced, by traversing the link or arc. U the
steam is admitted for a less portion of the stroke, depending upon the part of,
the link or arc U which is in gear with the valve H.
"
Sheet 2 is explanatory of another part of my Invention, which consists in;
admitting steam to both the cylinders of a pair of engines by means of a single
valve, perforated with suitable passages, and revolving on an axis continually
in one, direction; also in mounting revolving conical valves, used for admitting
steam, to the cylinders of steam, engines, on axes, which are set up by screws
or otherwise, so as to adjust the friction of the valve on its seat.
Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 17, 18, show one mode by which I carry
into effect this part of my Invention, and Figures 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, show, another mode.
In Figures 1, 2,3, 4, 5, 6, 7, 8, 9, 17, 18, A, B, are the steam cylinders.
S, a part of the steam pipe through which the steam passes to the cylinders;
V, a part of the exhaust pipe or passage through which the steam passes from
the cylinders to the condenser; C, a. vertical spindle or shaft on which the
part of the machinery marked D is fixed, and which is the main or principal

page_text: part of the valve arrangement... The shaft Cin the action; of the engine-is
made to revolve continuously in one direction by means of the toothed wheels:
E, E, of which E is placed on the shaft C, and E, on the crank, or other shaft
of the engine. The piece, D, which is secured to C, is round or circular at its
outer circumference, and revolves within a chamber of or belonging to the
steam cylinders, which chamber is made, as shownion, the Drawing, to fit it.
closely. The piece D is extended upwards beyond the chamber of the steam
cylinders; and. this upper part of the piece D revolves within a cylinderor
cliamber G, which can be turned round in either direction by means of i the.
hand-wheel. I, turning the spindle H on which is the toothed wheel H;
gearing or working into a toothed wheel, placed on the, outside, and at the
upper end of the chamber or cylinder, G. The steam in passing to the.
cylinders enters S, passes through the ports:G, Figure 4, which are made.in
the cylinder G, enters the passages D!; D; Figure 4, which two passages:D!
and two passages: D³, Figure 4; respectively joinzand: become the single:
passages D, D, Figure 5, from which passages:D, D, Figure 5, the steam:
issues through the ports made in the outer circumference of the piece D. into
the passages A'; B', A2, B2, as the piece D. revolves. The passages A', 'B¹,
A, B, Figure 5, are respectively connected, and communicate with the
passages. A, B, A, B, Figure: 1; and thus afford, means. of access for: the
steam to the steam-cylinders. In like manner the steam obtains egress from
the steam cylinders by passing through the passages A, B, A', B¹, Figure-1,
which are respectively part of the passages A, B, A, B, Figure 5, and by
entering the passages D3, D, Figures 1,. 3, 5, pass, through the.. pipe :or:
passage V, Figures 3, 5, which conduct: the steam to the condenser. Through
the chamber or cylinder.G there are two ports G. which at the same time
are open to the passage D, and also two ports G, which in like manner are
open at the same time to the passage: D. The. ports G are doubled in
number to afford larger access for the steam than is given through. one port
with the same size: of pieces D and G. The ports G, Figure 4, are placed:
on the Drawing equidistant in the circumference of G, and the width of these
ports.. G¹ circumferentially; as, also the placing and the width of the ports.
through the outside of D, which lead into the passages D', D', Figure 14,
require to be adjusted, so as to admit the steam: into the passages. D³, D²,
suitably for..its delivery into the passages A, B, A, B, Figure 5, and .to
admit a continuous passage of the. steam into the steam cylinders during such
short portion of the stroke as it may be desired to give steam to the cylinders:
The duration of the free influx of steam into the cylinders can be altered
somewhat by changing the position in a circumferential direction of the

page_text: chamber G, so as to keep open longer or close sooner the passage of the
steam through G into. D, D². The steam being admitted suitably into the
passages D', D, Figure 5, passes into the passages A, B, A3, B2, Figure 5,
by means of the ports, shown on the Drawing, which are provided for the
purpose, and these posts, which on the Drawing, Figure 5, are placed equi-
distant in the chamber belonging to the cylinder, must: in width, as also the
width and place of those in the piece D, be adjusted so as to admit the steam
properly at the commencement of each stroke of each piston, and during such
small portion of the stroke of the piston as may be desired. The piece D is
shown on the Drawing tapered or conical externally, and in Figures 1, 3, 8, 9,
is shown the provision made by which the piece. D can be adjusted, accu-
rately into its seat.. In Figures 1, 3, a pinching screw with jam nut is
shown, by which the, shaft C is prevented from being raised higher than is
desired; and in. Figures 8, 9, a wedge piece. marked C is shown, which is
adjustable to raise the shaft C. When the engines are in a position with one.
of the pistons at the commencement of a stroke, the valve piece D is in a
position with the proper port and passage open to the extent of the amount
of lead to admit steam, upon the piston, and the opening of the steam
passage increases as the piston begins the stroke; but if it be desired to
reverse the motion of the engine, that is, to make it move or work in a reverse
direction, the valve piece D, must be thrown.round circumferentially; so as to
have the opening of the steam passage; which is the lead for the commence-.
ment of a stroke, at the other side of the ports G¹, A', &c. and for that purpose
the spindle c is provided with a spiral or rather, angled feather, which projects
into a recess cut on the inside of the. tube or clutch F, which tube or clutch
F has a feather on its outside, placed parallelly with itself, and projecting
into a feather seat cut in the inside of the eye of the wheel E. The lever F,
Figures 1, 7, provides means by which the tube F3 can be withdrawn from or
pushed into the eye of the wheel E, and revolve or twist round. with it
circumferentially the shaft C, in the direction and to the extent necessary for
giving the valve piece D the change of position corresponding with the change
of. direction in. which the engine is to move. Figures 17, 18, explain a
mode of facilitating.. and perfecting the fit of the piece D: in its seat.
spindle C, at its upper end and lower end, where it bears in the collar bushes,
is made tapered, as shown.at C3, C4, Figures 17, 18, and the collar bushes,
which are parallel outside, are conical or tapered within, and wlien the piece
D with its. spindle C is placed properly in its seat, these conical collar bushes
can be fitted down. on their respective seats with the utmost accuracy, and
retain the piece D with the same accuracy in its position and place.
The

page_text: In Figures 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, which show another
mode of carrying out this part of my Invention, A, B, are the steam cylinders ;*
S, a part of the steam pipe through which the steam passes to the cylinders;
V, a part of the exhaust pipe or passage through which the steam passes fromi
the cylinders to the condenser; C, a vertical spindle or shaft on which the part
of the machinery marked D is fixed, and which is the main or principal part
of the valve arrangement. The shaft.C in the action of the engine is made
to revolve continuously in que direction by means of the toothed wheels E, E;.
of which E is fastened on the spindle C, and E' on the crank or other shaft of
the engine. The piece D, which is secured to and on C, is round or circular at
its outer circumference, and revolves within a piece or cylinder marked I. This
piece I is also round at its outer circumference, and is capable of revolution in `
either direction within the chamber of ór belonging to the steam' cylinders
which encloses it. Provision is made, as shown in Figure 12, to give this
piece I revolution, which provision consists of the hand wheel II', hollow
spindle II, and toothed wheel H on the hollow spindle.H, gearing or working
in a toothed wheel attached to the bottom of the picce I: The picce D is ex-
tended upwards beyond the piece I, and this upper part of the piece D revolvės
within a cylinder or chamber G, which can be turned round in either direction,
as shown in Figure 12, by means of the hand wheel. H', turning the spindle H
which passes up through the hollow spindle H on which spindle II! is
secured, the toothed wheel H gearing or working into a toothed wheel fastened
to the upper part of the cylinder or chamber G. The steam in passing to the
cylinders enters S, passes through the ports G', Figure 13, which are made in
the cylinder G, enters the passages D'; D, Figure 13, which two passages D
and two passages D2, Figure 18, respectively join and become the single
passages D', D, Figure 14, from which passages D', D3, Figure 14, the steam
issues through the ports made in the outer circumference. of the piece D as it
revolves into the passages A¹; B1, A2, B2, formed in the piece I. The passages
A', B', A2, B2,. Figure 14, which are in the piece I, respectively conimunicate
with the ends of the steam cylinders by opening into the passages A¹; B, A; B³
formed in the steam cylinders, and shown in Figure 10. In like manner the.
steam obtains egress from the steam cylinders by passing through the passages
marked A, B, A', B', in Figures 10, 14, into the passages D³, Ds, Figures 10,
12, 14, and thence through the pipe or channel V into the condenser. Through
the chamber or cylinder G there are two ports G¹, which at the same time are
open to the passage D¹, and also two ports G', which in like manner are open
at the same time to the passage D². The ports G¹ are doubled in number in
that way to afford larger access for the steam than is given through. one port

page_text: with the same size of pieces D'and G. The ports G₁, Figure 13, are placed
on the Drawing equidistant in the circumference of G, and the width of these
ports G₁ circumferentially, as also the placing and the width of the ports
through the outside of D, which lead into the passages. D', D', 'Figure 18,
require to. be adjusted so as to admit the steam into the passages D¹, D', suit-
ably for its delivery into the passages A, B, A3, B2, Figures 14, 10, and to
admit a continuous passage of the steam into the steam cylinders during such
short portion of the stroke as it may be desired to give steam to the cylinders.
The duration of the free influx of steam into the cylinders can be altered some-
what by changing the position in a circumferential direction of the chamber G,
so as to keep open longer or close sooner the passage of the steam through
Ginto D, D. The steam being adimitted suitably into the passages D', D
Figure 14, passes into the passages A, B, A, B, Figure 14, by means of the
ports; shown on the Drawing, which are provided for the purpose, and these
ports, which on the Drawing are placed equidistant in the piece. I, must in
width, as also the width and place of those in the piece D, be adjusted so as
to admit the steam properly at the commencement of each stroke of each
piston, and during such small portion of the stroke' of the piston as may be
desired. The passages A¹, B', A, B, in the piece I open into the several
passages.on or in the steam cylinder having the same marks by means of the
ports, for the purpose shown in Figure 10. The piece D is shown on the
Drawing tapered or conical externally, and by the provision, already described
it can be adjusted accurately in its seat, as shown in Figures 8, 9, 10, 12;
the same means also which are shown in Figures 17, 18, can be used for the
purpose of perfecting the fit of the piece D. in its seat. The piece I also is
tapered or conical externally; and the, pinching screws.L, L, afford the means
of adjusting it accurately into its seat.
:
In the mode shewn in Figures 1, 2, 3, 4, 5, 6, 7, 8, 9, 17, 18, of carrying out
this part of my Invention, I explained, that to reverse the motion of the engine.
provision is made by which the piece D is shifted in position, so as to, bring. the
ports formed in it to their proper places; insrelation to the ports shown in
Figure 4 and 5, formed in the chamber G, Figure 4, and in the passages A, B,
A2, B2, Figure 5; but in. the mode, which is shown in Figures 8, 9, 10, 11, 12,
13, 14, 15, 16, 17, 18, of carrying out my Invention,: I provide, that to reverse
the motion of: the engine, instead of changing the position; of the ports in the
piece D; I give the necessary change of position to: the ports formed in the
passages: A, B, A,B³, Figure 14, and when doing so the openings from these
passages into the passages' of the same marks, Figure 10, are not interfered
with, because these openings, Figure 10, are of such dimensions circumferentially

page_text: as to prevent it. As already explained, means are provided by which the piece I
can get a circumferential motion.
Having thus described the nature of my Invention, and the manner of per-
forming the same, I would have it understood that I do not confine myself to
the exact details described; but what I claim is,-
Firstly, the working the expansion valves of steam engines by means of
links, rods, or levers, connecting the same with reciprocating parts of the
engine, such as the side levers of the air pump, and also the making the con-
nection with such parts in such a manner that the extent of stroke of the
expansion valve may be varied as required. I also claim the giving motion to
expansion valves, when such valves are used in connection with engines in
which the cylinders are placed above the level of the crank shaft, by means of
a stem, which passes through the opposite end of the valve box to that through
which the stem of the ordinary valve passes.
Secondly, I claim the admitting steam to both the cylinders of a pair of
engines by means of a single valve, perforated with suitable passages, and
revolving on an axis continually in one direction. Also, the mounting revolving
conical valves used for admitting steam to the cylinders of steam engines on
axes, which axes are set up by screws or otherwise, so as to adjust the friction
of the valve on its seat.
In witness whereof, I, the said James Gray Lawrie, have hereunto set
my hand and seal, this Fourth day of November, in the year of our
Lord One thousand eight hundred and fifty-six.
Witness,
FRED. HARRIS.
J. G. LAWRIE. (L.S.)