CERTAIN IMPROVEMENTS IN PISTONS FOR STEAM ENGINES OR OTHER PURPOSES
Year: 1859

page_text: LETTERS PATENT to Henry Critchley, of Bury, in the County of Lan-'
caster, Engineer, and Solomon Elston, of the same Place, Engineer, for
the Invention of "CERTAIN IMPROVEMENTS IN PISTONS FOR STEAM ENGINES
OR OTHER PURPOSES."
Sealed the 24th June 1859, and dated the 13th January 1859.
PROVISIONAL SPECIFICATION left by the said Henry Critchley and
Solomon Elston at the Office of the Commissioners of. Patents, with their
Petition, on the 13th January 1859.
We, HENRY CRITCHLEY, of Bury, in the County of Lancaster, Engineer,
and SOLOMON ELSTON, of the same Place, Engineer, do hereby declare the
nature of our said Invention for "CERTAIN IMPROVEMENTS IN PISTONS FOR STEAM
ENGINES OR OTHER PURPOSES," to be as follows:-
Between the top and bottom flanges or plates of the ordinary piston is
situate our improved arrangement of mechanism for equalizing and continuing
the pressure upon interior of cylinder, and the mode of confining such means
of pressure from the action of steam, &c., in which such said piston works, the
improvements being. as follows:-Secured to or cast with the body of the
piston are a series of small cylinders or recesses constructed in such a manner,
that they shall divide the piston directly across its diameter on either side of
the piston rod, equally situated above each other for the purpose hereafter
described. Inserted into each of these small cylinders or recesses is the-end

page_text: of a spindle or stem, having a V head, this spindle being made a perfect fit to
the bore of such cylinder or recess, forming thereby a steam-tight slide;
these said spindles bedding in the interior of such recesses against spiral
springs, such springs exerting their force against the outer rings of the piston
through the medium of the spindles and V's afore-named, such rings being so
constructed or placed one above another, each one being divided in two or
more parts or segments, so that each segment shall be acted upon by the
afore-named V's, these segments being at their point of contact beviled to the
required angle of the V's, consequently. transmitting such pressure of springs
to the outer segmented rings of piston, thereby causing a uniform pressure
being constantly exerted upon interior of cylinder in which such piston works.
The top flange or plate of piston can be secured down in the ordinary manner
or cast solid, the under side being surfaced to the top ring making a steam-
tight joint, thereby forming a double barrier or preventative against the steam,
.&c., entering the recesses or cylinders in which the springs are confined.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said, Henry Critchley and Solomon Elston in the Great, Seal
Patent Office on the 13th July 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, HENRY
CRITCHLEY, of Bury, in the County of Lancaster, Engineer, and SOLOMON.
ELSTON, of the same Place, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of January, in the year of our Lord
One thousand eight hundred and fifty-nine, in the 22nd year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
Henry Critchley and Solomon Elston, Her special license that we, the said
Henry Critchley and Solomon Elston, our executors, administrators, and
assigns, or such others as we, the said Henry Critchley and Solomon Elston,
our 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 "CERTAIN IMPROVEMENTS IN
PISTONS FOR STEAM ENGINES OR OTHER PURPOSES," upon the condition, amongst
others, that we, the said Henry Critchley and Solomon Elston, by an instru-
ment under our hands and seals, should particularly describe and, ascer-

page_text: tain 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 monthis next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that we, the said Henry Critchley and Solomon Elston;
do hereby declare the nature of our said Invention, and in what manner.the
same is to be performed, to be particularly described and ascertained in and
by the following statement and accompanying Drawings, that is to say:
Our improvements in metallic pistons relate more particularly to the novel
arrangement of a series of small cylinders or recesses contained within the
interior of piston, also the peculiar construction of the several parts connected
therewith, for the cause of isolating or confining from the action of steam, &c.;
the means whereby a uniform and continuous pressure is constantly exerted
upon interior of cylinder in which such piston works, our arrangement being
as follows: "Cast solid with or between the top and bottom plates of the
ordinary piston is situated our peculiar combination of small cylinders or
recesses constructed at certain angles so that they shall divide the piston
directly across its diameter. These cylinders are supplied with springs which
are confined from the action of the steam, &c., by means of a ram, the bore of
the cylinder being equal to the diameter of such ram, forming thereby a
steam, air, or water-tight joint. From this ram, protruding into the interior
of the small cylinder, and of less diameter, is a spindle, around which the
spring coils; the opposite end of this ram, outside the small internal cylinder,
being formed into a V or wedge fitting and bedding against the bevilled ends
of packing rings, allowing by such contact the action of the springs confined
the cylinder, and pressing against the rams, to distribute a continuous
uniform pressure against the bevilled ends of such packing rings, thereby
transmitting and exerting a force or friction against the interior surface of the
cylinder in which such piston works sufficient to form a perfect steam, air, or
water-tight joint. The packing consists of two rings placed together, each
ring being divided into two or more segments (each segment being acted upon
by the springs through the medium of rams and spindles afore-named,) such
rings being turned and ground to the top and bottom plates so as to prevent
the steam from passing into the interior of piston, thereby forming along with
the small cylinders, and there connecting mechanism a double barrier or pre-
ventative against the steam, &c., entering the afore-named cylinders or
recesses in which the springs are confined.
In order that our Invention may be more clearly understood, we have here-
unto attached a Sheet of Drawings made upon a scale of about three inches

page_text: to the foot, having similar letters of reference marked upon corresponding parts
of the apparatus in all the Figures alike.
Fig. 1 is the plan view of a piston having the top plate removed (the piston
in this case not being cast solid) shewing the internal arrangement of cylinders
with their V-headed rams in contact with the bevilled ends of packing rings;
Fig. 2 is a sectional elevation of same, shewing more particularly the position
and arrangement of small internal cylinders in respect to the top and bottom
packing rings, this view having the rams, &c., withdrawn; and Fig. 3 is an
enlarged sectional view of one of the small internal cylinders, shewing the
position of the several parts in working order."
a, a, is the body or block of piston, to which is cast or secured our novel
arrangement of small internal cylinders or recesses b, b, b, b, for the purpose
of containing the elastic medium c, shown more particularly in Fig. 3; these
springs are so confined within the cylinders b, &c., by means of the rams d,
that they are perfectly isolated from the action of steam, &c. The spindle f
of the ram around which the spring coils protrudes into the small cylinder b
allowing sufficient clearance in the said cylinder for any necessary compression
of springs by the rams d, the springs transmitting such pressure in a continuous
uniform manner through the medium of such rams d and V heads g to the
segmented packing rings h.
Having now described and fully illustrated our improvements, we, wish, in
conclusion, that it should be distinctly understood our claim consists of the
novel arrangement and construction of internal cylinders or recesses with the
connecting apparatus, as more particularly shown and described in Fig. 3, for
the purpose of isolating or confining from the action of steam, &c., the means
whereby a continuous uniform pressure is constantly exerted upon interior of
cylinder in which such piston works.
In witness whereof, we, the said Henry Critchley and Soloman Elston,
have hereunto set our hands and seals, this 6th day of July, in
the year of our Lord One thousand eight hundred and fifty-nine.
HENRY CRITCHLEY.
SOLOMON ELSTON.
(L.S.)
. (L.S.)
HENRY CRITCHLEY.
SOLOMON ELSTON.
(L.S.)
. (L.S.)