IMPROVEMENTS IN STEAM ENGINES
Year: 1875

page_text: LETTERS PATENT to Thomas Moy, of 37, Farringdon Street, in the
County of Middlesex, Engineer, for the Invention of "IMPROVEMENTS
IN STEAM ENGINES."
Sealed the 22nd February 1876, and dated the 25th August 1875.
PROVISIONAL SPECIFICATION left by the said Thomas Moy at the
Office of the Commissioners of Patents, with his Petition, on the
25th August 1875.
·I, THOMAS MOx, of 37, Farringdon Street, in the County of Middlesex,
Engineer, do hereby declare the nature of the said Invention for " IM-
PROVEMENTS IN STEAM ENGINES," to be as follows:-
My Invention relates to that class of steam engines described in the
Specification of a Patent granted to me and one Richard Edmund Shill,
bearing date October 18th, 1871, No. 2762, and consists in adapting and
applying to such engines the arrangements herein-after stated.
LA frum the sides of the steam

page_text: are arranged on one or more sides or faces of the water chamber, hent
tubes being fitted to each plate so as to admit of their becoming heated
as required.
The steam and water chamber are combined in one metallic structure,
which is bolted to the bottom or end plate of the casting containing the
cylinders, valve chest, and their appurtenances, and the said structure
with the tube plate or platės applied thereto forms an enclosure for the
cylinders, valve chest, and appurtenances.
The bottom or end plate to which the said structure is bolted is
supported on pillars or on any suitable frame. One tube plate only is
used in preference to 2 or more plates in cases wherein sufficient
heating surface can be obtained thereby. Such tube plate may be either
circular, square, or otherwise in form, with the tubes arranged as closely
together as practicable, in order to arrest and utilise the heat applied
thereto.
The only necessary fittings to the steam and water chamber are tho
safety valve, the pressure and water gauges, and the tube plate and
fire-box casing.
Framings of various forms may be used to suit the position of the
cranks and axle.
Two cylinders are sometimes used double acting and of suitable sizes
to form compound engines, the steam being admitted to the small
cylinder by means of a semicircular valve in a circular valve box, and
the cut off or amount of expansion being effected by a flat plate or flat
plates on the back thereof. No receiver is required when the cranks
are placed at a distance of 180 degrees apart, as the steam passes
directly from the high-pressure cylinder to the low-pressure cylinder.
When however the cranks are placed at right angles to each other a
receiver is necessary, and two valve boxes are preferred, cutting off the
steam in each cylinder at the same portion of the stroke.
In some cases 3 cylinders are made use of, being of 3 different
sizes and double acting, but of the same length of stroke. With 3
cylinders 2 receivers are employed, and the cranks may be set at
angles of 120 degrees in relation to each other, and the cut off effected
with common slide valves or with the above-named semi-cylindrical
valves, or with Moy's expanding ring valves, as described in the Speci-
fication No. 977 (1874).

page_text: In other cases where a high speed is required in the revolutions of the
shaft, 2 or three single acting cylinders are used, so as to have the
pressures always in one direction to the crank shaft, and thereby effect
a high speed without noise. I also pass the steam over a considerable
portion of tube surface on its way to the cylinder, in order that it may
expand to its proper capacity, and to reduce its saturation.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Moy in the Great Seal Patent Office
on the 25th February 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
Moy, of 37, Farringdon Street, in the County of Middlesex, Engineer,
send greeting.
1.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of August, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Thomas Moy, Her special
licence, that I, the said Thomas Moy, my executors, administrators,
and assigns, or such others as I, the said Thomas Moy, 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
Thomas Moy, 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 Thomas Moy, do hereby declare
the nature of my said Invention, and in what manner the same is to

page_text: be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the Drawings here-
unto annexed, and to the letters and figures marked thereon (that is to
say)
My Invention of "Improvements in Steam Engines" relates to that
class of steam engines described in the Specification of a Patent granted]
to me and one Richard Edmund Shill, bearing date October Eighteenth,
One thousand eight hundred and seventy-one, No. 2762, and consists in
adapting and applying to such engines the arrangements herein-after
stated.
Instead of making the tube plates to form the sides of the steam
generator as described in the said Specification, one or more plates is or
are arranged on one or more sides or faces of the water chamber, bent
tubes being fitted to each plate so as to admit of their becoming heated
as required.
The steam and water chamber are combined in one metallic structure,
which is bolted to the bottom or end plate of the casting containing the
cylinders, valve chest, and their appurtenances, and the said structure
with the tube plate or plates applied thereto forms an enclosure for the
cylinders, valve chest, and appurtenances.
In cases wherein such structure would be inconveniently large in one
piece, it may be put together in any of the ordinary modes employed in
boiler making.
The bottom or end plate to which the said structure is bolted is sup-
ported on pillars or on any suitable frame. One tube plate only is used
in preference to two or more plates, in cases wherein sufficient heating
surface can be obtained thereby. Such tube plate may be either circular
or square, or otherwise in form, with the tubes arranged as closely
together as practicable, in order to arrest and utilize the heat applied
thereto.
The only necessary fittings to the steam and water chamber are the
safety valve, the pressure and water gauges, the tube plate, and fire-box
casing, and ordinary lagging.
Framings of various forms may be used to suit the position of the
cranks and axle.
Two cylinders, are sometimes used double-acting, and of suitable sizes

page_text: to form compound engines, the steam being admitted to the small
cylinder by means of a semicircular valve in a circular valve box, and
the cut-off or amount of expansion being effected by a valve, which may
be either flat or semicircular in form on the back thereof. No receiver
is required when the cranks are placed at a distance of one hundred and
eighty degrees apart, as the steam passes directly from the high-pressure
cylinder to the low-pressure cylinder. When however the cranks are.
placed at right angles to each other a receiver is necessary, and two
valve boxes are preferred, cutting off the steam in each cylinder at the
same portion of the stroke. When a receiver is used it is contained
within the steam and water chamber.
In some cases three cylinders are made, use of, being of three different
sizes and double-acting, but of the same length of stroke. With three
cylinders two receivers are employed, and the cranks may be set at
angles of one hundred and twenty degrees in relation to each other, and
the cut-off effected with common slide valves, or with the above-named
semi-cylindrical valves, or with Moy's expanding ring valves, as described
in the Specification, No. 977 (1874).
In other cases, where it is desirable that a very high speed is required
in the revolutions of the shaft, two or three single-acting cylinders are
used, so as to have the pressures always in one direction to the crank-
shaft, and thereby effect a high speed without noisć. I also pass the
steam over a considerable portion of tube surface on its way to the
cylinder in order that it may expand to its proper capacity and to reduce
its saturation.
Having thus stated the nature of the said Invention, I will proceed
to describe more particularly in what manner the same is to be performed
by the aid of the accompanying Drawings, in which are represented the
parts of a steam engine above referred to.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is an elevation of so much of the engine and generator as is-
essential for the present purpose. 7 is the reservoir for steam and
water, in which the cylinders, valve chest, valves, and steam pipe are
contained.

page_text: Fig. 4 represents the tube plate shewing one arrangement of the
tubes.
Fig. 5 is a horizontal section on the line a, b, of Figures 1 and 2. c¹ is
the small steam cylinder; c is the large steam cylinder; d is the valve
chest, and e is the eduction passage; fis the regulator..
Fig. 6 is a section on the line g, h, of Fig. 1 showing the framing
and cylindrical guides for the cross heads and guide for the valve
rods.
Fig. 7 is an external elevation of the reservoir as sometimes formed
for horizontal engines.
The water level in the reservoir is kept a little bigher than the tubes,
so that all the tubes may be kept full of water. Heat being applied to
the external surfaces of these tubes causes the water to circulate therein,
entering at the lower end and passing out as water and steam at the
upper end, as in the said former Patent.
The arrangement shown in Fig. 1 is for a series of gas burners as the
source of heat, but other forms are used for other 'kinds of fuel, as
described in the former Patent.
The Drawings here shown represent a compound engine with two
cylinders, the cranks of which are one hundred and eighty degrees apart.
Steam enters the small cylinder through the steam pipe n, and is cut off
at any suitable portion of the stroke by the valves, and passes directly
from one cylinder to the other by means of the arrangement of valves
and ports as shown in Figures 8 to 19.
I have described in the Provisional Specification the valve as being
semi-cylindrical with a flat back, and having a flat cut-off valve working
on its back, and I sometimes use such valves, but I prefer valves being
formed after the manner shown in Figures 9 to 18.
The valve rods are shown of a semi-cylindrical form, two such rods
placed together, as in Fig. 18, are employed to work the valves, the
rod o actuating the main valve, and the rod p the expansion valve.
Fig. 9 is a side view of the main valve with the valve rod o in situ ;
Fig. 10 is a longitudinal section of the same without the valve rod; and

page_text: does not cool down and condense, such engines may be stopped and
started with great facility by means of a stop-cock or valve fitted upon
the eduction pipe, such means being used for short stoppages and for
starting quickly, leaving the ordinary induction steam cock or regulator
open.
Under my present Invention the particular improvements consist
mainly in the greater facility afforded of constructing the cylinders and
valves and working parts generally, independently of and unencumbered
by the reservoir, and in making the several parts more portable and
divisible than by the several modes of construction described in the
Specifications of the Patents herein-before referred to, while at the same
time retaining the advantages thereof.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I hereby declare that I do not
claim any particular proportion of expansive action of the steam, or any
particular number of cylinders or valves, but what I do claim as of my
Invention is,—
First. The mode of constructing the reservoir independently of the
engine hercin-before described, as an improvement on the modes
described in the Specifications of former Patents referred to.
Secondly. The mode described of working the valves and the two
semicircular valve rods.
And, lastly. The stop-cock or valve on the eduction pipe for the
purpose described.
In witness whereof, I, the said Thomas Moy, have hereunto set a
my hand and seal, the Twenty-third day of February, in the year
of our Lord One thousand eight hundred and seventy-six.
Witness,
WILLIAM SPENCE,
8, Quality Court,
Chancery Lane.
THO. MOY. (L.S.)