AN IMPROVED METHOD FOR TIGHTENING PISTON RINGS TO THE CYLINDERS OF STEAM OR OTHER ENGINES
Year: 1869

page_text: LETTERS PATENT to Thomas Henry Martin, of Swansea, in the
County of Glamorgan, Engineer, for the Invention of "AN IMPROVED
METHOD FOR TIGHTENING PISTON RINGS TO THE CYLINDERS OF STEAM OR
OTHER ENGINES."
Sealed the 3rd August 1869, and dated the 18th February 1869.
PROVISIONAL SPECIFICATION left by the said Thomas Henry Martin
at the Office of the Commissioners of Patents, with his Petition,
on the 18th February 1869.
I, THOMAS HENRY MARTIN, of Swansea, in the County of Glamorgan,
Engineer, do hereby declare the nature of the said Invention for "Ax
IMPROVED METHOD FOR TIGHTENING PISTON RINGS TO THE CYLINDERS OF STEAM OR
OTHER ENGINES," to be as follows:-
This Invention consists of an improved mode of tightening the piston
rings of pistons so as to make them fit more exactly in the cylinders,
thereby keeping their places better and exerting more power than
hitherto.

page_text: This is accomplished by placing a movable valve or valves in the
body of the piston, which valves are opened and closed by the working
pressure (of whatever kind, whether of air, steam, water, or gas, or of
other fluids or liquids) on either side of the piston, thereby causing a
continual pressure (equal to the working pressure on either side of the
piston) to act against the inner sides of the metallic rings composing the
piston, thus continually pressing them against the sides of the cylinders
whilst the engine (to which the piston is attached) is at work. The
piston may or may not be made with or without the top or lug ring,
and the circumference of the rings may be in one or more parts and
secured by tongue pieces. The valve or valves may be made either
single or double, and placed opposite to each other or otherwise as may
be found most convenient.
The advantages gained by this Invention comprise the following
amongst the chief features:-The economizing the entire cost of the top
or lug ring, dispensing with the bolts, nuts, and such like fastenings,
also with the springs and bolts used in the construction of ordinary
spring pistons, and with the common packing with white yarn, vul-
canized india-rubber, and lead, and there will be great saving in labor;
prevention of delays in opening the cylinder and of the loss of power to
the engines on account of the springs, rings, and packing losing their
elasticity.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Henry Martin in the Great Seal Patent
Office on the 4th August 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
HENRY MARTIN, of Swansea, in the County of Glamorgan, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of February, in the
year of our Lord One thousand eight hundred and sixty-nine, in
the thirty-second year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Thomas Henry Martin,
Her special licence that I, the said Thomas Henry Martin, my execu-
tors, administrators, and assigns, or such others as I, the said Thomas

page_text: Henry Martin, 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 "AN IMPROVED METHOD FOR TIGHTENING PISTON RINGS TO THE
CYLINDERS OF STEAM OR OTHER ENGINES," upon the condition (amongst
others). that I, the said Thomas Henry Martin, 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 Henry Martin, 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 in writing, and on reference being had to the
accompanying Sheet of Drawings, that is to say :-
This Invention consists of an improved mode of tightening the piston
rings of pistons so as to make them fit more exactly in the cylinders,
thereby keeping their places better and exerting more power than
hitherto.
:
This improved method is accomplished by placing a movable valve or
valves in the body of the piston, which valves are opened and closed by
the working pressure (of whatever kind, whether of air, steam, water, or
gas, or of other fluids or liquids) on either side of the piston, thereby
causing a continual pressure (equal to the working pressure on either
side of the piston) to act against the inner sides of the metallic rings
composing the piston, thus continually pressing them against the sides
of the cylinders whilst the engine (to which the piston is attached) is at
work. To allow for the wear of the outer rings, and to prevent noise,
the inner ones are made with a little spring, i.c., they are made a
little larger in diameter, and a piece cut out, so that they can be placed
or forced within the outer ones, and continually press them against the
side of the cylinder. The piston may or may not be made with or
without the top or lugg ring, and the circumference of the rings may be
in one or more parts and secured by tongue pieces. The valve or valves

page_text: may be made either single or double, and placed opposite to each other
or otherwise as may be found most convenient.
The advantages gained by this Invention comprise the following
amongst the chief features:-The economizing the entire cost of the
springs, bolts, and nuts used in the construction of ordinary spring
pistons, and with the common packing with white yarn, vulcanized
india-rubber, and lead, and there will be great saving in labor, also in
fuel, and prevention of delays in opening the cylinders and of the loss,
of power to the engines on account of the springs, rings, and packing
losing their clasticity.
Such being the nature and object of my said Invention for "An
Improved Method for Tightening Piston Rings to the Cylinders of Steam
or other Engines," I will now proceed to describe more in detail the
manner in which the same is to be or may be performed or carried into
practical effect; and in order that the same may be distinctly understood
I have annexed hereunto a Sheet of Drawings illustrative thereof, and
have marked with Figures and letters of reference corresponding with
those in the following explanation thereof, that is to say :-
On the accompanying Sheet of Drawings Figure 1 represents a plan
of piston with a top or lugg ring and fitted with my improvements;
Figure 2, a vertical section (through the line A, B, Figure 1) of the
same; and Figure 3 a side elevation of the valve.
a is the valve placed in the body of the piston, having chambers 6
(Figure 2) formed in its interior. Around the walls of these chambers
and communicating with the interior of the piston are any convenient
number of ports or openings c, d; these, as the piston is forced up or
down, alternately communicate with the interior of the piston, and the
water, air, gas, steam, or whatever the working pressure may be first
enters either of the chambers b, and then passes through either the
parts c or d (as the piston is being forced up or down) into the interior e
of the piston, and there presses or tightens the rings f of the piston
against the sides of the cylinder.
Having now described the nature and object of my said Invention for
"An Improved Method for Tightening Piston Rings to the Cylinders of
Steam or other Engines," together with the manner in which the same
is to be or may be performed or carried into practical effect, I would
remark in conclusion that I claim as my Invention, the improved
method and means of tightening piston rings, substantially as herein-

page_text: before described and illustrated on the accompanying Sheet of Drawings,
or any mere modification or variation thereof in shape or otherwise.
In witness whereof, I, the said Thomas Henry Martin, have
hereunto set my hand and seal, this Twenty-eighth day of July,
in the year of our Lord One thousand eight hundred and sixty-
nine.
THOMAS HENRY MARTIN. (L.S.)