IMPROVEMENTS IN LOCOMOTIVE STEAM ENGINES (PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO OTHER ENGINES).
Year: 1872

page_text: LETTERS PATENT to William Dawes, of Kingston Grove, Leeds, in
the County of York, Engineer, for the Invention of "IMPROVEMENTS
IN LOCOMOTIVE STEAM ENGINES (PARTS OF WHICH IMPROVEMENTS ARE ALSO
APPLICABLE TO OTHER ENGINES)."
Sealed the 13th August 1872, and dated the 20th June 1872.
PROVISIONAL SPECIFICATION left by the said William Dawes at the
Office of the Commissioners of Patents, with his Petition, on the
20th June 1872.
I, WILLIAM DAwes, of Kingston Grove, Leeds, in the County of York,
3 Engineer, do hereby declare the nature of the said Invention for "IM.
PROVEMENTS IN LOCOMOTIVE STEAM ENGINES (PARTS OF WHICH IMPROVEMENTS ARE
ALSO APPLICABLE TO OTHER ENGINES)," to be as follows :—
The first part of my Invention has reference to economy in the
quantity of steam required for a given load, speed, and distance, and
consequently in the quantity of both fuel and water necessary for
producing the same, and it may be understood from the following
description, viz. :-I so arrange the cylinders and valves of my engines
as to obtain an average expansion of about eight to twelve times

page_text: "
"exhaust" steam of both the small cylinders passes into a general receiver
or other equivalent, and thence to both the larger cylinders, making
"
as it were a pair of small "high pressure" cylinders for one driving
axle and pair of wheels, and a pair of larger and lower pressure
cylinders for the other driving axle and pair of wheels, the cranks in
each pair or engine being as usual set at "right angles," or 90 degrees
from each other. To insure in this arrangement a proper maintainance of
the steam pressure between the two pairs of cylinders, or in other words,
between the two engines, I sometimes construct or "finish" the driving
wheels of the larger cylindered engine somewhat larger in diameter
(say one-eighth of an inch) than those of the smaller cylindered engine,
.and I attach a safety or "relief" valve in connection with the before-
named "receiver" or "mid exhaust" steam to prevent excessive or
accumulative pressure therein.
The third part of my Invention consists in part in a modified
application or arrangement of the first and second parts either jointly or
separately according to circumstances, and whether the before-named
results or effects are to be realized in entirely new or in previously
made engines altered to embody my improvements. It may be thus
described Instead of employing my two pairs of cylinders as or in
the manner herein-before described, I sometimes constitute one small
and one large cylinder a "pair" (i.e. one engine), and the other two
(also one small and one large) the other "pair" or engine, each of these
pairs or engines being coupled or attached ("geared") to its own
driving axle and wheels; then to ensure a good position of each (as the
pistons in each pair of cylinders then work simultaneously) I couple
the two driving axles and their wheels by mechanical means, such as
" bands," chains, or "connecting rods," and in all cases where it is
possible I prefer to do this inside the wheels and framing of the engine
or "from axle to axle" instead of "from wheel to wheel" outside as
heretofore, and for further insuring the perfect balance and freedom
from rocking or oscillation which this and the second part of my
Invention are intended to produce (by dispensing with the outside
couplings) I prefer when using the "connecting rod" and crank
method to balance the weight of these by projections or weights upon
the back ends or "cheeks" of the cranks to which the connecting or
'coupling" rods are attached. Also, I sometimes prefer to connect,
couple, or "gear" all my cylinders (as two pairs, each pair being one
65

page_text: small and one large) to one of the driving axles, and to work or actuate
the other driving axle and wheels from this by any of the before-named
inside methods of "coupling" or by the ordinary method where these
may not be convenient. I also in some cases employ an automatic
arrangement of parts, cocks or valves, whereby the engine driver can
cause (at certain times, such as starting from stations, "shunting," or
other similar occasions) the steam to act direct upon all the pistons, but
this only with a slow movement or action of the pistons and engine,
and therefore available only for the before-named times and purposes
and no other, as the arrangement of these parts and their connection
with the "reversing lever" render compulsory.
:
cross
"
The fourth part of my Invention may be thus described :-In "carrying
out," arranging, or constructing my herein-before described "four
cylindered expansive locomotive engine," I sometimes find it desirable
to use or adopt the "oscillating cylinder" principle to one or both pairs
of cylinders for the sake of compactness, and dispensing with "
head slides or guides, and in so doing I use for the "trunnions in
lieu of the "packing boxes" heretofore employed, and considered as
indispensable in oscillating cylinders, an elastic ring or diaphragm of
thin metal uniting a stronger or rigid metal ring to either the stationary
or the oscillating part or collar of the pipe or trunnion," the latter and
the corresponding part or collar against which it rests and works being
"faced" and made "steam-tight" (similar in section to the relief part
or portion of the slide valve for which I obtained Letters Patent, No. 35,
A.D. 1869), and I thus obtain a permanent elastic and steam-tight
onnection or "packing box substitute" between the cylinders and the
steam and exhaust pipes, and in thus dispensing with the "trunnion
packing boxes" heretofore employed I render the oscillating cylinder
principle available as herein-before explained. I also in some cases
employ the before-named "packing box substitute" to the rods or
'spindles" of the main or cylinder valves of my engines, giving them
a vibratory or oscillatory movement from the excentric rods, and coupling
or connecting them to the valves (to impart the necessary
"travel" or
"to-and-fro" motion) by inside "links" or any other similar or con-
venient means or method. It will be evident that this (fourth) part
of my Invention is also applicable to other engines as well as to
"locomotives."
"

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Dawes in the Great Seal Patent Office
on the 20th December 1872.
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 niost Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of Junc, in the year
of our Lord One thousand eight hundred and seventy-two, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, 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 exe-
cutors, 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
LOCOMOTIVE STEAM ENGINES (PARTS OF WHICH IMPROVEMENTS ARE ALSO APPLICABLE.
TO OTHER 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 par-
ticularly 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 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 Drawings,
and to the letters of reference marked thereon, that is to say :-
The first part of my Invention has for its object increased economy
in the quantity of steam required for a given load, speed, and distance
travelled, and consequently in the quantity of both fuel and water
necessary for producing the same, and it may be understood from the
following description, viz.:-I so arrange the cylinders and valves of my
engines as to obtain an average expansion of about eight to ten times
(instead of 4 to 6 times as heretofore) from the original volume and

page_text: pressure of steam during its passage through or time of use or duty
in the said engines, and to accomplish or realize and render practical
this increased rate or ratio of expansion, which is the necessary and
only means of obtaining the required degree or amount of economy
(and which is impracticable in any previous or existing "type" or
"make" of locomotive engine) I use in lieu of the one pair of cylinders
and pistons heretofore employed two pairs of cylinders and pistons so
arranged or used, and proportioned as regards their "strokes" and
areas, that a difference of about "four or five to one" exists between
the areas and capacities of each pair, or between the small and
large cylinders of each pair as the case may be or require, and thus
(the steam passing from the smaller to the larger) according to this
difference and the time of "cutting off" the steam in the smaller
cylinders will be the entire rate, ratio, or degree of expansion produced,
"half stroke" giving an expansion of eight to ten times, and one-
third that of twelve to fifteen times as before explained, and as will
be understood by all engineers. I also encase or "steam jacket
"
at least the smaller of the steam cylinders to prevent undue or objec-
tionable condensation, and in altering or "converting " the present or
existing engines into my "compound economic " engines, this may be
done by retaining the present cylinders for the outer casing or "jacket
of the smaller cylinders, and fitting as a "shell" or plain tube the
11
"

page_text: entire revolution of the "driving wheels" (which are presumed to be
the same diameter in each case), and thus with exactly 3rds the quantity,
of steam of the same pressure 426 lbs. more force is obtained, making the
result not less than as 3 to 2 or 3rd saved or 150 miles travelled (with
the same load and speed) with the same consumption of fuel and water
which has heretofore been required for 100 miles; and it may be well to
mention that this reduction in the demand upon or "forcing" of the
"fire box," bars, and boiler will effect a still greater saving in the
wear and tear" of these latter parts. Another incidental advantage is
also palpable, viz., a less "percussive" and more even or uniform power
upon the driving wheels and consequently less liability to "slip" and
more tractive power.
"E
"
.
"
The second part of my Invention has reference more especially to the
stability or steady running at high speeds of what are now known as
coupled engines," and is to a certain extent, when fully carried out,
dependant or consequent upon the first part of my Invention. When so
carried out I attach or gear" my two before-named pairs of cylinders
in manner following, viz. :-I cause both of the two smaller ones to work
upon or give the power or "thrust" of their pistons to the cranks of one
of the "driving wheel" shafts or "axles," and I cause both of the two
larger cylinders to work upon or give the power or "thrust" of their
pistons to the other "driving wheel shaft or "axle;" and I thus constitute
each pair of wheels so worked or acted upon ("actuated") a complete
and independent pair of driving or "traction" wheels capable of
doing its "duty" or share of propulsion more thoroughly, evenly, and
efficiently (uncoupled except by the steam) than when coupled by the out-
side "coupling" or connecting rods heretofore employed for increasing
the adhesive and tractive power of such engines and which are productive
of instability, wear, and danger. It may be well to explain that when my
cylinders are so used or arranged (i.e. for two pairs of "driving wheels" to
be actuated by the steam without the intervention or use of "coupling"
or connecting rods) the "mid exhaust" steam from both the smaller
cylinders passes into a general receiver or other equivalent and thence
to both the larger cylinders, making as it were a pair of small "high
pressure" cylinders for one driving axle and pair of wheels, and a pair
of larger and lower pressure cylinders for the other driving axle and pair
of wheels, the cranks to each pair or "engine" being set at "right
angles" (or 90 degrees) from each other as usual.

page_text: "
The third part of my Invention consists in part in a modified appli-
cation or arrangement of the first and second parts, either jointly or
separatily, according to circumstances, and whether the before-named
results or effects are to be realized in entirely new or in previously made
("existing ") engines altered to embody my improvements. It may be
thus described :-I so arrange or employ my four cylinders that the power
or thrust of their pistons is given in the first instance entirely to one
driving axle" and pair of wheels, say, the "leading" wheels, and in
such a manner that the next or "centre" pair of wheels and axle can be
coupled to and worked or actuated by or from the first pair, and that by
inside "coupling or connecting rods and cranks, and thus I obtain the
additional tractive power without outside "coupling rods," and secure
greater stability and less strain and "wear and tear," as herein-before
explained. I also in some cases employ one or more small valves (either
"slide" or "lifting ") in connection with the boiler, steam, and the steam
chest or chests of the larger cylinders, whereby the engine driver can
cause at certain times (such as starting from stations, "shunting," or
other similar occasions) the steam to act direct upon all the pistons;
but I not only keep this valve and aperture very small (say, th of a
square inch), but I also arrange it so that the "starting" or "reversing"
lever only, or some other part of the valve gear connected therewith,
shall be able to open this valve and communication, and it or they shall
only be able to do so when pushed to the extreme distance or limit for
either "forward" or "backward movement of the engine, which occurs
only at such times as the before-named, and this valve being self-closing-
and therefore "shut" at all other times no danger can accruce from

page_text: "
sides between) being "faced" and made " steam-tight" (similar in
section and arrangement to the relief frame and diaphragm shown in
my Patent, No. 35, 1869), and I thus obtain a permanent clastic and
steam-tight connection ("trunnion") or 'packing box substitute”
between the cylinders and the steam and exhaust pipes, and in thus
dispensing with the "trunnion packing boxes" heretofore employed I
render the "oscillating cylinder" principle or "make" of engine available
for locomotive engines as herein-before explained, I also in some cases
employ the before-named permanent "packing box substitute" to the
valve rods or "spindles" of the main or cylinder valves, giving them
a vibratory or oscillating movement from the eccentric, and coupling
them to the valves by links or otherwise inside the steam chest. It
will be evident that this (fourth) part of my Invention is also applicable
to other engines as well as to locomotives.
In consideration of the somewhat peculiar nature of my Invention,
and the fact of its applicability to existing engines, and their great
number and variety, I have preferred to use as illustrations in my
Drawings such arrangements as will suit generally both these and
entirely new ones, stating only that Fig. 1 shows an arrangement
applicable to "inside cylinder" engines, Fig. 2, an arrangement appli-
cable to "outside cylinder" engines, Fig. 3, an arrangement with the
'oscillating cylinders" and inside coupling rods, and Fig. 4, an enlarged
section of the permanent elastic" trunnion."
"
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I wish it to be understood that I do not confine or
restrict myself to the precise details or arrangements which I have
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 hercin-before in
part recited Letters Patent is,—
Firstly. Increasing the economic working of locomotive engines by
increasing the practical ratio or degree of steam expansion by the use
of additional or "compounding" cylinders and retaining with them the
use of the "blast muzzle" for increasing the fire draught in lieu of
condensing the final exhaust steam which appears to have been hereto-
forc considered essential in all "compound" expansive engines.

page_text: Secondly. Improving the stability of "coupled engines" (so called)
by causing the steam to act upon two pairs of "driving wheels" and
thus give the tractive power without actual coupling by rods or other
mechanical means.
Thirdly. An arrangement of engine wherein two pairs of driving |
wheels can be coupled by inside coupling rods in lieu of the outside ones
heretofore employed.
Fourthly. The arrangement and construction of a permanent elastic
metallic "packing box substitute" for the "trunnions" of oscillating
cylinders, and the valve rods of all engines essentially as or after the
manner of the foregoing descriptions and accompanying Drawings.
In witness whereof, I, the said William Dawes, have hereunto set
my hand and seal, this Seventeenth day of December, in the year
of our Lord One thousand eight hundred and seventy-two.
Witness,
J. W. HARDING,
Engineer & Patent Agent,
2, East Parade,
Leeds.
WILLIAM DAWES. (L.S.)