IMPROVEMENTS IN STEAM ENGINES
Year: 1871

page_text: LETTERS PATENT to William Dawes, of Kingston Grove, Leeds, in
the County of York, Engineer, for the Invention of "IMPROVEMENTS
IN STEAM ENGINES.”
Sealed the 14th November 1871, and dated the 16th May 1871.
PROVISIONAL SPECIFICATION left by the said William Dawes at
the Office of the Commissioners of Patents, with his Petition, on
the 16th May 1871.
I, WILLIAM DAWES, of Kingston Grove, Leeds, in the County of
York, Engineer, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN STEAM ENGINES," to be as follows :—
The first part of my Invention consists in an improved arrangement
or construction of steam engine, either vertical or horizontal, but is
more especially applicable to vertical "compound engines" for marine
purposes; it may be thus described :- Upon a pair of "A" or other
suitable standards or convenient "frame" I fix the two steam cylinders
" inverted," "side by side," and in such a position that their centres
and piston rods stand longitudinally over the crank shaft and at a.

page_text: bar or
"
proper height or distance from it for the action of the connecting rod
as in the ordinary "inverted engine," the ends of the piston rods being
fitted with adjustable "brasses' or brass bearings for encircling and
working upon "pins" or upon turned bearing surfaces at the ends of a
gudgeon" of a proper length for these "necks' or bearing
surfaces to " agree with" or work inside the said brasses of the piston
rods. I then construct a "reeling" or vibrating frame of sufficient
width (at the small or "free" end) to fit or work between the said
piston rod ends, and into this I fit and fix in a substantial manner
either the before-named "pins" or "gudgeon." The back end of this
' reeling or vibrating frame is somewhat wider, larger, and stronger
than the "free" or "
vibrating" end, and the whole must be of such
strength and construction as to be free from " spring" or
either at the starting or during the working of the engine.
68
"
" torsion'
"
The large
or back end of this reeling frame is also fitted with similar "pins" or
gudgeon" to the smaller end, and the distance between these, that is,
the length of the frame from "centre to centre" of the pins, may be
about once and one half that of the "stroke" of the engine; the said
reeling or vibrating frame is carried or supported at the larger end
by or upon a second reeling or vibrating frame, in this instance vertical,
and furnished at its top end with adjustable bearings or brasses to receive
or fit upon the said " pins' or gudgeon" in the larger end of the first
named (horizontal) reeling or vibrating frame, the bottom also of the
second or vertical reeling frame being furnished with
"pins or
gudgeon" and bearings ("pedestals") secured to the sole plate or
other convenient fixed part of the engine.
66
"
"
I must now explain that by fitting another pair of " pins" into the
sides of the first-named (horizontal) reeling frames, and a similar pair
into the sides of the "A frames" or standards, and by connecting these
pairs by a strong pair of "radius rods," I obtain a "parallel motion" and
true geometrical guide for the piston rod ends, in lieu of the slides and
sliding blocks generally used in "direct acting" engines, which for
vertical engines are objectionable on account of the exposed and down-
ward tendency of the oil or lubricating material, the extra quantity
required, and withal the amount of friction which ensues. The
connecting rod constructed as usual, and fitted to and working upon
the crank or "crank pin" in the usual manner, is attached at its upper
end to the said horizontal reeling frame, its adjustable "brasses"
encircling or fitting upon the middle part of the said bar or "gudgeon"
"

page_text: "
between the two piston rods, or upon an extra short pin or
gudgeon"
(when the separate pins are used) fixed to the reeling frame for this
purpose.
It may also be well to explain that this horizontal "reeling frame"
may be made available for working the "air pumps," "circulating
pumps," or "boiler pumps," and will do so in a simple, direct, and
efficient manner.
It will also be seen and understood that by this arrangement of parts
and the use and application of the "anti-torsion" reeling frame I avoid
double length piston rods and inside packing boxes, and the extra
height or length of engine which they require, I obtain a safe and
simultaneous action of the two pistons with one connecting rod, and at
the same time am enabled to dispense with slides and use in lieu thereof
a simple and efficient "parallel motion," which is especially preferable
in vertical engines as herein-before explained.
The foregoing description is that of one vertical "compound" engine,
which may be duplicated in the usual manner according to circumstances,
and it will be evident that the said "anti-torsion" frame may be advan-
tageously employed in other arrangements or kinds of engine as well as
in the herein-before described arrangement.
"
The second part of my Invention, though applicable in part to all
expansive steam engines, refers more especially to compound engines,
whether vertical or horizontal, and for whatever purpose they may be
required, and the improvement may be considered as a new method or
means of extending or further developing the combined effect or result
of the two principles of working steam expansively, single and com-
pound; it may be thus described:-After constructing my "compound
engine as herein-before described, or in any convenient manner as
regards the general arrangement of engine, I make certain alterations
in the "valves," "ports," and "passages of the cylinders, so as to
obtain an increased result or "duty" from a given quantity of fuel,
namely, I so arrange the valve or valves and ports of the high-pressure
cylinder that after admitting or escaping" its "exhaust steam," as
heretofore, into the steam chest of the low-pressure cylinder, say, when
the high-pressure piston has moved about one-eighth of its stroke, I
close this connection or direction of its exhaust, and whilst retaining
this exhaust steam as usual for its action upon the "steam side" of the
large or low-pressure piston, I open a connection between the front or
"

page_text: "
exhaust side of the high-pressure piston and the condenser, so as to
prevent the usual neutralizing effect of the small piston upon the large
one in compound engines, and also obtain the additional effect or result
of the "
vacuum action upon the small piston.
"
This part of these improvements may be realized or "carried out"
either by altering the usual slide valve or valves, or by the employment of
an additional valve, as the case may require.
" 66
Then, as a means of further carrying out these improvements and
increasing the efficiency and power of the engine, I allow each single
"stroke" of the engine a rapid or "momentary' puff" of steam at
the full pressure to enter the steam chest of the large or low-pressure
cylinder, for the double purpose of "superheating" or "reheating" and
expanding by direct contact and admixture the exhaust steam of the
small or high-pressure cylinder, and also of obtaining an increased
expansion, and therefore benefit or result from the "steam action" or
pressure (apart from the vacuum) in the large cylinder. I prefer that
this rapid or momentary "puff" of high-pressure steam should take
place at the same time that the "vacuum " is admitted upon the small
piston, or the moment after the exhaust steam has entered and is
secured in the low-pressure steam chest; and for this purpose I prefer
to use a separate "gridiron "slide valve with narrow ports and short
stroke or travel, actuated by a cam" and roller action for the purpose
of controlling this intermittent action or admission of steam, the valve
being caused to open and close again by one straight action or motion
each single stroke of the engine; and it will be evident that from the
great effect of this steam upon the large area of the low-pressure piston,
and the fact that the quantity of steam admitted each "puff" will depend
upon the speed at which the said "gridiron" valve passes from one side
to the other, and also that this speed must be according to that of the
engine itself, the faster the engine is running the less will be the
quantity of steam admitted, and "vice versa," and that therefore this
will constitute a kind of " self-governing" action or medium, and will
greatly assist in maintaining the "steady running" and speed of the
engine.
66
It may also be well to explain that this admission of high-pressure
steam upon the low-pressure piston takes place at such a time or
position of the engine, and is confined to such a small part or portion
of the full stroke of the piston, that no damage, strain, or breakage can

page_text: arise therefrom, also that the direct effect or "duty" obtained from
the steam thus used is (owing to its great expansion) fully equal to
that obtained from the other portion of the entire quantity of steam
consumed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Dawes in the Great Seal Patent Office
on the 15th November 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
DAWES, of Kingston Grove, Leeds, in the County of York, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of May, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Dawes, Her special licence
that I, the said William Dawes, my executors, administrators, and
assigns, or such others as I, the said William Dawes, 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
William Dawes, 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 William Dawes, 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
following statement thereof, that is to say:-
The first part of my Invention consists in an improved arrangement.
or construction of steam engine, more especially applicable to vertical

page_text: "
66
"
"
"
cr
"
compound engines" for marine purposes; it may be thus described :—
Upon a pair of "A" or other suitable standards or convenient frame a, a,
I fix the steam cylinders b, b, inverted "side by side" and in such a
position that their centres and piston rods stand longitudinally over the
crank shaft, and at a proper height or distance from it, for the action
of the connecting rod, as in the ordinary "inverted engine," the ends
of the piston rods being fitted with adjustable "brasses
or brass
bearings for encircling and working upon "pins," or upon turned
bearing surfaces at the ends of a bar or gudgeon" of a proper length
for the necks or bearing surfaces to agree with or work inside the said
brasses at the piston rod ends, see Figures 1 and 2, Sheet 1. I also
construct a reeling" or vibrating frame c, c, of sufficient width at the
small or free end to fit or work between the said piston rod ends, and
into this I fit and fix in a substantial manner either the before-named
pins" or gudgeon to receive the piston rods, and between them
the upper end of the connecting rod. The back end of this reeling or
vibrating frame is somewhat larger and stronger than the free or
vibrating end, and the whole must be of such strength and construction
as to be free from " spring" or " torsion' either at the starting or
during the working of the engine. The large or back end of this
reeling frame is also fitted with similar "pins or "gudgeon to the
smaller end, and the distance between these, that is, the length of the
said frame from centre to centre of the pins, may be about once and
one half that of the stroke of the engine. The said reeling or vibrating
frame is "carried" or supported at the larger end by or upon a second
reeling or vibrating frame d, d, in this instance vertical, and furnished
at its top end with adjustable brasses or bearings to receive or fit upon
the said pins or gudgeon in the larger end of the first-named (horizontal)
reeling an vibrating frame, the bottom also of this second or vertical
reeling frame d, d, being furnished with "pins" or "gudgeon" and
bearings (pedestals) secured to the sole plate or other convenient fixed
part of the engine.
"
"
"

page_text: piston rods, in lieu of the slides and sliding blocks generally used in
"direct-acting" engines, which for vertical engines are objectionable,
on account of the exposed and downward tendency of the oil or lubri-
cating material, the extra quantity required, and with all the undue
amount of friction which ensues. The connecting rod, constructed as
usual, and fitted to and working upon the crank or crank pin in the
usual manner, is attached at its upper end to the free end of the said
horizontal reeling frame c, c, its adjustable brasses encircling or fitting
upon the middle part of the said bar or gudgeon between the two piston
rods, or upon an extra short pin or gudgeon (when the separate pins
are used) fixed to the reeling frame for this purpose.
It may also be well to explain that this horizontal reeling frame and
the radius rods used as pump levers constitute a convenient means of
working the air pumps and boiler pump, and in such a manner that
their duty shall constitute a counterbalance to the weight of the pistons,
&c. instead of increasing the "want" or absence of " balance," as is the
case in the ordinary inverted engine.
It will thus be seen and understood that by this arrangement of parts
and the use and application of the "anti-torsion reeling frame" c, c,
I avoid double-length piston rods and inside "packing boxes," and the
extra height or length of engine which they require, I obtain a safe
and simultaneous action of the two pistons with one connecting rod,
and at the same time am enabled to dispense with "slides," and use in
lieu thereof a strong and efficient "parallel motion," which is especially
preferable in vertical engines, as herein-before explained.
"
The foregoing description is that of one vertical "compound engine,"
which may be duplicated in the usual manner, according to circum-
stances, and it will be evident that the said "anti-torsion reeling frame
may be advantageously employed in other arrangements of direct-acting
steam engines, as well as in the herein-before described arrangement.
The second part of my Invention, though applicable in part to all
expansive steam engines, refers more especially to "compound engines,"
whether vertical or horizontal, and for whatever purpose they may be
required; and the improvements may be considered as a new method
or means of extending or further developing the combined effect or
result of the two principles of working steam expansively, "single"
compound." It may be thus described, after constructing my
and "

page_text: compound engine as herein-before described, or in any convenient or
desirable manner as regards the general arrangement of the engine:
I make certain alterations in the "valves," 'ports," and "passages
of the cylinders, so as to obtain an increased result or "duty" from a
given quantity of fuel; namely, I so arrange the valve or valves and
"ports" of the high-pressure cylinder that after exhausting or escaping
its "exhaust steam," as heretofore, into the "steam chest" of the low-
pressure cylinder, say, when the piston has moved about one-sixth of its
stroke, I close this communication or direction of its exhaust, and
whilst retaining this "mid exhaust" steam as usual for acting upon the
"steam side" of the large or low-pressure piston, I open a communi-
cation between the front or exhaust side of the high-pressure piston and
the condenser, so as to prevent the usual neutralizing or retarding effect
of the small piston upon the larger one in compound engines, and
also obtain the additional effect or result of the vacuum action" upon
the front face or area of the small or high-pressure piston.
15
"
This part of these improvements may be realized or "carried out
either by altering the usual slide valve (see Figure 5, Sheet 2) or
valves, or by the employment of additional valves, as the case may
require.
"
66
Then, as a means of further carrying out these improvements and
increasing the efficiency and power of the engine, I allow each single
stroke of the pistons or engine a rapid, momentary, or "instantaneous "
"puff" of hot steam at the full pressure and temperature to enter the
steam chest of the large or "low-pressure" cylinder, for the double
purpose of "superheating or reheating" and expanding by direct
contact and admixture the exhaust steam of the small or high-pressure
cylinder, and also of obtaining an increased expansion, and therefore
benefit or result from the steam action or pressure (apart from vacuum)
in the large cylinder. I prefer that this rapid or instantaneous puff
of hot steam should take place at the same time that the vacuum is
admitted upon the small piston, or the moment after the "mid exhaust"
steam has entered, and is secured or
"caged " in the low-pressure
steam chest, and for this purpose I prefer to use a separate "grid-
iron slide valve with narrow "ports" or openings, and short stroke or
travel," actuated by a cam and roller action. For the purpose of
controling this intermittent action or admission of steam (see Figure 6,
Sheet 2), the said " gridiron" valve being constructed to open and
"
66
"

page_text: close again by one straight or single action or motion, each single stroke
of the engine, and it will be evident that from the effect of this combined
steam upon the large area of the low-pressure piston, and the fact that
the quantity of steam admitted each "puff" will depend upon or be
governed by the speed at which the said gridiron valve passes from side
to side, and also that this speed must be according to that of the engine
itself, the faster the engine is running the less will be the quantity
of hot or "
superheating" steam admitted, and "vice versa," and that
therefore this will constitute a kind of "self-governing" action or
medium to this half or part of the engine, and will greatly assist in
maintaining the "steady running" and speed of the engine.
It may be necessary to explain further that this admission or
"instantaneous puff" of hot or high-pressure steam upon the low-
pressure piston takes place at such a time or position of the engine,
and is confined to such a small part or portion of the full stroke of the
engine, that no damage, strain, or breakage can result therefrom, and
also that the ratio or proportion of effect or "duty" obtained from the
steam thus used is (owing to the number of times it is expanded) fully
equal to that obtained from the other portion of the entire quantity of
steam consumed.
Having now described and particularly ascertained and shown the
nature of the said Invention, and the manner in which the same is or
may be used or carried into effect, I wish it to be understood that
I do not confine or restrict myself to the precise details which I have
shown, described, or referred to, as many modifications and variations
may be made therefrom without deviating from the principles or main
features of the said Invention, but 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,―
Firstly. The improved arrangement and construction of direct-acting
compound engine, embracing especially the use and application of the
"anti-torsion reeling frame," for the purposes herein-before described
and set forth.
And, secondly. The improved arrangement or construction of the
valves and ports, and the use and application of the single motion
gridiron valve, for the purpose of reducing the conflicting or neutralizing
effect of the mid exhaust, and further improving (by the latter) the
general result and economy by the "instantaneous " 'puff" method

page_text: or principle of superheating and governing, essentially as or after the
manner of the foregoing descriptions and Drawings.
In witness whereof, I, the said William Dawes, have hereunto
set my hand and seal, this Fourteenth day of November, in
the year of our Lord One thousand eight hundred and seventy-
one.
Witness,
FRANCIS HENRY STUBBS,
Malvern Place,
Hunslet.
WILLIAM DAWES. (L.s.)