IMPROVEMENTS IN PISTONS FOR STEAM ENGINES DRIVEN BY STEAM OR ANY OTHER ELASTIC FLUID, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO THE PISTONS OR PLUNGERS OF PUMPS
Year: 1858

page_text: LETTERS PATENT to Edward Wilson, of 9, Rainbow Terrace, Worcester,
for the Invention of "IMPROVEMENTS IN PISTONS FOR STEAM ENGINES
DRIVEN BY STEAM OR ANY OTHER ELASTIC FLUID, WHICH IMPROVEMENTS ARE
ALSO APPLICABLE TO THE PISTONS OR PLUNGERS OF PUMPS."
Sealed the 25th June 1858, and dated the 19th January 1858.
PROVISIONAL SPECIFICATION left by the said Edward Wilson at the
Office of the Commissioners of Patents, with his Petition, on the 19th
January 1858..
I, EDWARD WILSON, of 9, Rainbow Terrace, Worcester, do hereby declare
the nature of the Invention for "IMPROVEMENTS IN PISTONS FOR STEAM ENGINES
DRIVEN BY STEAM OR ANY OTHER ELASTIC. FLUID, WHICH IMPROVEMENTS ARE ALSO
APPLICABLE TO THE PISTONS OR PLUNGERS OF PUMPS," to be as follows:-
My improvements consist in applying one metallic packing ring only, the
joint or opening of which is a compound half-lap joint, and may be placed in
any position of the piston or plunger, and prevented or not moving therefrom
by a tong or stop-pin. The packing ring is placed in a recess turned or formed'
in the piston head or plunger, and is forced against the internal surface of the
cylinder, and rendered steam, air, or water-tight by its own elasticity, which is
obtained by slightly hammering the internal surface of the packing ring, or
by placing a light metallic spring against the internal surface of the packing
ring.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Wilson in the Great Seal Patent Office on the
15th July 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
WILSON, of No. 9, Rainbow Terrace, Worcester, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of January, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Edward Wilson, Her special licence that I, the said Edward Wilson, my
executors, administrators, and assigns, or such others as I, the said Edward
Wilson, 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 PISTONS
FOR STEAM ENGINES DRIVEN BY STEAM OR ANY OTHER ELASTIC FLUID, WHICH
IMPROVEMENTS ARE ALSO APPLICABLE TO THE PISTONS OR PLUNGERS OF PUMPS,"
upon the condition (amongst others) that I, the said Edward Wilson, 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 Edward Wilson, do hereby declare
the nature of the 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 thereof, that is to say:-
My improvements consist in applying one-metallic packing ring only, the
joint or opening of which is a compound half-lap joint, and -may be placed in
any position of the piston or plunger, and prevented or not moving therefrom
by a tong or stop pin. The packing ring is placed in a recess turned or
formed in the piston head or plunger, and is forced against the internal surface
of the cylinder and rendered steam, air, or water-tight by its own elasticity,
which is obtained by slightly hammering the internal surface of the packing
ring, or by placing a light metallic spring against the internal surface of the
packing ring.

page_text: And in order that my said Invention may be fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plan, partly in section, of a piston constructed according to
my Invention; Figures 2, 3, and 4 are transverse sections, showing different
modes of applying my improvements; Figure 5 is an edge view, partly in
section, shewing an adaptation of my improvement to an ordinary piston head;
Figures 7, 9, and 10 are plans; and Figures 12, 13, 14, and 15 are edge
views, and Figures 6, 8, 11, and 16 are transverse sections, all drawn full size,
of different modifications of my compound lap joint for the packing ring.
a, a, is a piston head, furnished with a groove or recess e, e, around its peri-
phery for the reception of the packing ring c, c; b, b, is a portion of the piston
rod, which may be firmly attached to the piston head by a screw and lock nut,
as shown, or in any other convenient and ordinary manner; f,f, (Figures 1, 3,
4, 9, and 10) is a light metallic spring, which may be introduced as shewn, if
desired, to assist in keeping the packing ring in contact with the cylinder.
The sides of the packing ring c, c, should be made a good working fit to the
sides of the groove e, e, and the outer circumference turned or otherwise made
to fit the cylinder truly.
I will now proceed to describe my compound lap joint, one modification of
which is shewn by Figures 6, 7, 8, 9, 12, and 13; the packing ring is halved
or scarped for a portion of its depth or thickness, as shewn at 9, g, Figures 7,
8, 9, 12, and 13, for about half the length of the joint and for the remaining
length of the joint, as well as below the scarp of the other end, one of the ends
of the packing ring is furnished with an under horizontal lap, as shewn
at h, h.
Figures.6, 7, 8, 9, 12, and 13: this compound lap joint will be clearly under-
stood by examining Figure 6, which is a cross section of the joint at y, y,
Figure 7; and Figure 8, which is a cross section at z, z, Figure 7; the surfaces
of these laps and scarps should be made a good working fit, so that when the
ring expands, by wear or otherwise, the surface of such laps and scarps may
remain in perfect contact with each other.
Figures 11, 15, and 16 shew another modification of my compound lap
joint, in which the one end of the packing ring is furnished with two sides or
jaws i, i, Figures 11, 15, and 16, and with an under lap k, k, Figures 11, 15,
and 16, forming a recess for the reception of the other end of the packing
ring. The under lap in all modifications may be either recessed into the other
end, as shewn in Figures 7 and 9, or left in excess of the depth of the packing

page_text: ring, as shewn in Figure 11. Where this modification is used it is necessary
that the groove e, e, should be made with an enlarged space for receiving the
jaws i, i, as shown at 1, 1, Figure 5.
When it is desired to prevent the packing ring c, c, turning in the groove e, e,
a stud or studs may be introduced, attached either to the inner circumference
of the packing ring c, c, and fitting into corresponding holes made in the piston
head a, a, or attached to the piston head a, a, and working in corresponding
holes made in the packing ring. In pistons working horizontally it may be
advantageous to have two such studs placed upon the opposite sides, so that
they will support the weight of the packing ring, and so prevent undue pressure
upon the under side of the cylinder.
Where it is desired to apply my improvements to ordinary piston heads, it
may easily be effected by introducing a cast or other metallic block, as shewn
at d, d, Figure 5, to fill up the space occupied by the ordinary packing rings;
in the periphery of this block the groove c, c, is formed, and my packing ring
introduced, in the same manner as before described. This arrangement is
shewn in Figure 5..
Having thus described the nature of my Invention, and the manner of per-
forming the same, I would have it understood that I do not confine myself to
the exact details described; but what I claim is, the constructing metallic
packings or packing rings with a compound half-lap joint, as herein described.
In witness whereof, I, the said Edward Wilson, have hereunto set my
hand and seal, this Fourteenth day of July, in the year of our Lord
One thousand eight hundred and fifty-eight.
Witness,
RICHARD WOOD,
of the City of Worcester,
Gentleman.
EDWARD WILSON. (L.S.)