Im- PROVEMENTS IN THE CONSTRUCTION OF PISTONS FOR STEAM ENGINES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO AIR AND LIQUID PUMPS
Year: 1862

page_text: LETTERS PATENT to Abraham Ripley, of Brook Street, West Square,
Lambeth, in the County of Surrey, Engineer, for the Invention of "Im-
PROVEMENTS IN THE CONSTRUCTION OF PISTONS FOR STEAM ENGINES, WHICH
Sealed the 24th April 1863, and dated the 29th October 1862.
PROVISIONAL SPECIFICATION left by the said Abraham Ripley at the
Office of the Commissioners of Patents, with his Petition, on the 29th
October 1862.
I, ABRAHAM RIPLEY, of Brook Street, West Square, Lambeth, in the
County of Surrey, Engineer, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS FOR STEAM ENGINES,
WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO AIR AND LIQUID PUMPS," to be as
follows, that is to say :-
My Invention consists in causing the rings composing the packing of the
piston to expand so as to exactly fit the cylinder by means of the pressure of
the steam, air, or liquid. To effect this I form on the periphery of the block
or portion into which the piston rod is fitted a double cone, the exterior
packing ring I place over this, leaving a small space between the two; within
this space is another ring, the interior having the same angle, and accurately
fitting one of the cones before mentioned, the outside pressing against the
exterior packing ring; a corresponding ring is fitted to the other cone, which
also presses against the outside packing ring. Through each cover of the
piston are several studs or projections (preferably 3), which touch the edges of

page_text: the inside rings, so that when the steam is admitted on either side of the
piston it will press the studs down, thus acting upon and enlarging the inner
rings by forcing them further over the cone, and consequently the exterior
packing ring. By calculating the surface of the studs or projections any
degree of pressure can be obtained.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Abraham Ripley in the Great Seal Patent Office on the 29th
April 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ABRAHAM
RIPLEY, of Brook Street, West Square, Lambeth, in the County of Surrey,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of October, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Abraham Ripley, Her special licence that I, the said Abraham Ripley,
my executors, administrators, and assigns, or such others as I, the said
Abraham Ripley, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times.there-
after 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 "IMPROVE-
MENTS IN THE CONSTRUCTION OF PISTONS FOR STEAM ENGINES, WHICH IMPROVE-
MENTS ARE ALSO APPLICABLE TO AIR AND LIQUID PUMPS," upon the condition
(amongst others) that I, the said Abraham Ripley, my executors or adminis-
trators, 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 Abraham Ripley, 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 state-
ment, that is to say:-
This Invention relates to the pistons of steam engines, air, and other
pumps, and consists of certain improvements in the construction of the said

page_text: pistons, and the object of the said Invention is the production of a piston
which shall permanently possess a self-maintaining steam-tight expanding
metal packing, the expansion being constantly maintained by the pressure of
the steam, air, or other fluid itself. To effect this, on the periphery of the
block or solid portion of the piston into which the piston rod is fitted, I turn
or form a double cone, upon this cone I fit two expanding cone rings or ring
wedges, which rings are cut through at one side, or formed into segments,.to.
allow them to expand as they are pressed over the solid cone before mentioned;
on the outside of these cone rings, wedges, or segments I fit the metal. packing
ring, and cover the whole above and below, or on both sides of the piston. with
covering plates, or "jonk ring plates," which plates are fixed upon the solid
portion of the piston, and bolted thereto and together by suitable bolts passing
through the whole in the usual way; round the edges of these plates, and
immediately over the coned ring wedges I insert a number of small pressure-
studs or minature pistons, which are fitted steam, air, or liquid-tight therein.
by packing or otherwise; these studs or minature pistons rest upon the coned
ring wedges inside, and are either flush with or project a little beyond the
jonk plates outside the piston, so that when the steam, air, or fluid is
admitted on either side of the piston in the cylinder, pump, or other vessel,
it will press upon the studs, and driving them inwards, will force them against
the coned ring or segment wedges, and causes them to expand as they are
pressed over the solid cone of the piston, and thus expand the outer metal
packing until it fills and exactly fits the cylinder on all sides, and as both sides
of the piston are similarly fitted, the moving force will maintain the air,
vapour, liquid-tight condition from the commencement to the termination
of every stroke effectually and permanently. The working pressure of the
steam being known, the size of the studs may be calculated, so as to obtain
any degree of packing pressure required.
awing
strate
the mode of constructing the improved piston described in the foregoing
statement.
Fig. 1 shews an outside view of one of these pistons; Fig. 2, a section
through the centre thereof; and Fig. 3, a sectional plan with half of one of
the covering or jonk ring plates removed, to shew the top of the solid cone,
expanding or ring wedges, and also shews the line of section A, B, through
which Fig. 2 is taken; Fig. 4 is an enlarged section through the edge of the
piston, and shews the form of the pressure studs or minature pistons.

page_text: The following reference applies to Figs. 1 to 4 inclusive. a is the solid
plug or body of the piston, upon the periphery of which the double cone is
formed for expanding the ring wedges; b, b, the cone rings or inner expanding
ring wedges; c, the outer metal packing ring; d, d, the covering plates or
jonk rings in which the miniature pistons e, e, are fitted; f, opening left
between the coned ring to allow for this being pressed inwards and expand
over the solid cone when impelled by the force at the steam or fluid acting
upon the miniature pistons, thus causing the outer packing ring also to expand
and take the exact form of a transverse section of the cylinder at all parts of
the stroke, thereby maintaining the steam or liquid-tight condition, notwith-
standing any irregularities in the cylinder arising from imperfect boring,
previous unequal wearing, or other causes. When necessary the miniature
piston heads may be fitted with flexible diaphragms for increasing their power,
and increasing their steam or vapour-tight action.
Figs. 5, 6, and 7.shews a modification of my improvements in which the
inner expansion rings are formed in segments, and the miniature pistons are
coupled by an adjusting screw. g, the body of the piston; h, h, h, the
segmental expanding rings; i, i, the coupled miniature pistons acted upon by
the steam or fluid, as before described; k, the coupling and adjusting screw
for setting the said pistons when required to compensate for the wear of the
outer expansion ring. This adjusting screw k is fitted into one of the
miniature piston heads, and is free to turn therein; the opposite piston head is
tapped to receive the screw, which on being turned to the right or left
increases or diminishes the distance between their surfaces for expanding the
inner pressure rings h, h. In the head of the adjusting screw a square hole is
sunk to receive a key for turning it, and in the hole immediately above it a
screw clamping collar with a similar but rather lather keyway is fitted;
this collar when screwed down upon the head of the adjusting screw prevents
it from turning by the motion of the piston or its parts when it is required to
move the screw; this collar is turned and first raised by its key, when the
screw key being passed through the keyway in the collar turns it as required,
this done, it is again fixed by screwing down the collar upon it, as before
described.
Fig. 8 shews another modification of my said improvements, in which
instead of turning the solid centre of the piston at the periphery in the form
of a double cone, I give it the segmental form here shewn, and between this
centre m and the packing ring o I insert an expanding ring of segments n;
which are actuated by a miniature piston p, p, as before explained. The least
thickness of the segments is in the centre at 1, 1, and as their thickness

page_text: increases towards 2, 2, and 3, 3, it will be evident that any motion thereof
towards either sides of the piston from the position shewn will cause the ring o
to expand and fit the cylinder, as before described.
Having thus described and ascertained the nature of my said Invention,
and illustrated the manner the said improvements may be carried into effect in
practice, I hereby further declare that I do not absolutely restrict myself to
the precise forms and dimensions shewn upon the Drawings; but I include all
such modifications in design in the various details as the principle of my said
Invention will admit.
In witness whereof, I, the said Abraham Ripley, have hereunto set my
hand and seal, this Twenty-ninth day of April, One thousand eight
hundred and sixty-three.
A. RIPLEY. (L.S.)