MENTS IN STEAM ENGINE CYLINDERS
Year: 1864

page_text: Sealed the 8th August 1864, and dated the 8th February 1864.
PROVISIONAL SPECIFICATION left by the said Thomas Snowdon at
the Office of the Commissioners of Patents, with his Petition, on the
8th February 1864.
IMPROVE
I, THOMAS SNOWDON, of Stockton-on-Tees, in the County of Durham,
Engineer, do hereby declare the nature of the said Invention for
MENTS IN STEAM ENGINE CYLINDERS," to be as follows, that is to say :-
This Invention has for its object improvements in the cylinders of steam
engines, and consists,-
First, in making the cover or covers instead of the usual flat form with a
recess or inverted disk, having sufficient space above, beyond, or outside the
flange (where the covers are usually bolted to the cylinder flange) to receive
the piston, making these covers in fact to form part of the cylinder, so that
when the improved covers are detached the piston can be examined, repaired,
or the rings and plates taken out and replaced without otherwise removing
the piston from its position or from the cylinder altogether.
נם.
IMPROVE
Engineer, do hereby declare the nature of the said Invention for
MENTS IN STEAM ENGINE CYLINDERS," to be as follows, that is to say:-
This Invention has for its object improvements in the cylinders of steam
engines, and consists,-
First, in making the cover or covers instead of the usual flat form with a
recess or inverted disk, having sufficient space above, beyond, or outside the
flange (where the covers are usually bolted to the cylinder flange) to receive
the piston, making these covers in fact to form part of the cylinder, so that
when the improved covers are detached the piston can be examined, repaired,
or the rings and plates taken out and replaced without otherwise removing
the piston from its position or from the cylinder altogether.
D

page_text: And, secondly, in making the steam ports in such cover or covers by placing
them at each end.
And, thirdly, in so forming the said covers that the waste steam is con-
ducted over them through suitable apertures or perforations to keep the parts
in contact with the interior of the cylinder hot.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Snowdon in the Great Seal Patent Office on the
8th August 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
SNOWDON, of Stockton-on-Tees, in the County of Durham, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of Feby, in the year of our Lord
One thousand eight hundred and four, in the 26th year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me,
the said Thos. Snowdon, Her special licence that 1, the said Thos.
Snowdon, my exccutors, administrators, and assigns, or such others as
I, the said Thos. Snowdon, 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 ENGINE CYLINDERS," upon the condition (amongst
others) that I, the said Thos. Snowdon, 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 Thos. Snowdon, do hereby declare
the nature of I 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:
This Invention relates to steam and blowing engines, and has for its object
improvements in the cylinders, cylinder lids, and cylinder connections,
the said improvements consist,--

page_text: Firstly, in an improved cylinder cover, and consists in making the cover in
the form of an inverted dish, the recess of which (from the flange of the
cylinder where the ordinary flat covers are usually bolted on) is of a depth
equal to the thickness of the piston, and into which the piston works when at
the end of the stroke, so that when it is necessary to examine the piston by
placing the engine on the centre or end of the stroke, and then removing the
cover, the piston, packing ring or rings are out of the cylinder, and can be
examined or removed, be repaired, or replaced without detaching the piston
rod from the cross head.
Secondly, in forming the steam and other ports in the said lids, and in
fitting an improved slide or equilibrium valve upon the port connection, by
which arrangement and improved valve all the advantages of the ordinary flat
side are obtained (viz.), large areas of steam and exhaust ports, and at the
same time the rubbing surface on the face of the valve is greatly diminished,
and in addition to which the pressure in the back of the slide is considerably
relieved if not entirely obviated by a loose jacket.
Thirdly, in an improved air and steam superheating and atmospheric
cylinder or "surface condensing cylinder. This cylinder is fitted with a number
of tubes, the united areas of which ought to be equal to the outlet passages
from the blowing cylinder to which it is proposed one end of the said cylinder
shall be attached, the other end to be fixed to the air main or tube; thus the
whole of the air discharged from the blowing cylinder will pass through the
tubes in the condensing cylinder, whilst the exhaust steam (in whole or in
part from one or both the steam cylinders) being discharged into the body of the
condenser will be brought in contact with the surface of the tubes (which said
surface should be equal to the heating surface of the boilers used), and will
be condensed by the refrigerating action caused by the passage of the air from
the blowing cylinder to the air main or tube before mentioned, a supply of
pure water will at the same time thus be obtained for the use of the boilers,
and at the same time the temperature of the air from the blowing cylinder
will be considerably increased previously to its entering the hot air stoves, the
condensed water, and any gases arising therefrom, may be extracted from the
condensing cylinder by an air pump attached to the engine.
Fourthly, in placing a steam cylinder on each side of the air or blowing
cylinder.
In carrying out these improvements, I do not confine myself to having both
the steam cylinders of equal dimensions (as shown in the Drawing, they are
intended to work as high-pressure engines), but I prefer that only one

page_text: cylinder shall take the steam direct from the boiler, and that the steam shall
be cut off at such part of the stroke as may be found most suitable; then the
exhaust steam may be made to pass through the fixed cylinder, which acts as
a superheater, and heats the steam before it enters the second cylinder, which
I propose shall be of a larger area than the first cylinder, and then be used in
the ordinary manner. The cubical content of the steam space of the super-
heater ought to be at least equal to the cubical content of the second steam
cylinder, and which superheater I prefer to heat with the waste or other gas
from the blast furnaces.
The general forms of the said improved cylinders, lid, and valves, and
mode of forming a blowing engine therewith are shewn upon the accompanying
Drawings, lettered A, B, and C respectively.
EXPLANATION OF THE DRAWINGS.
Drawing A. Figure 1 is an elevation, Fig. 2 a vertical section, and Fig. 3.
a plan of the top of the improved cylinder and cover. a is the recess formed
in the lid; b, the cylinder flange; c, the lid flange; d, the piston shewn as at
the top of the stroke, and where it is out of the cylinder when the lid is
removed.
The other Figures on this Drawing relate to the valve, which forms one of
the improvements in the said cylinders or engines.
Fig. 4 is a longitudinal section of the steam chest; Fig. 5 is a sectional
plan thereof, shewing the cylinder end arrangement; Fig. 6, an inside view
of the loose jacket of the valve; and Fig. 7, an elevation of the slide. a is
the cylinder; b, the enlargement; c, the valve: d, the loose jacket;
e, e, springs between the outer and loose jacket for keeping the latter up to
the face and also to allow the valve to be pushed off the face when there is
any water in the cylinder, and so prevent any breakage arising therefrom;
f, f, steady pins to keep the jacket in position.
Drawing B.-This Drawing shews one of the improved steam and air
heating condensing cylinders, which may form a part of the steam cylinder, or
be attached thereto or connected therewith.
Fig. 1 is a plan, and Fig. 2 a cross section, through the line A, B, Fig. 1,
and shews the mode of fitting the heating and condensing tubes. a is the inlet;
b, the outlet; c, the exhausting inlet; e, the outlet junction to attach to
pump; f, f, the pipes.
Drawing C. This Drawing shews a three-cylinder engine in which the
cylinders are placed side by side.

page_text: Fig. 1 is a front elevation, and Fig. 2 a side elevation.
a is the first or
high-pressure cylinder; b, the low-pressure cylinder; c, the blowing cylinder;
and d, the condensing cylinder.
Having thus described, illustrated, and explained the said improvements, I
hereby further declare that I do not absolutely restrict myself in practice
to the precise details shewn upon the Drawings, as these may be variously
modified when required without departing from the integrity and principle of
my said Invention.
In witness whereof. I, the said Thomas Snowdon, have hereunto set my
hand and seal, this 25th day of July, in the year of our Lord One
thousand eight hundred and sixty-four.
THO. SNOWDON. (L.S.)