IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS
Year: 1868

page_text: LETTERS PATENT to Joseph Quick, the younger, of Sumner Street,
Southwark, in the County of Surrey, Civil Engineer, and John
Sampson, of Battersea Park, in the same County, Engineer, for the
PROVISIONAL SPECIFICATION left by the said Joseph Quick and John
Sampson at the Office of the Commissioners of Patents, with their
Petition, on the 17th December 1868.
We, JOSEPH QUICK, the younger, of Sumner Street, Southwark, in the
County of Surrey, Civil Engineer, and JOHN SAMPSON, of Battersea Park,
in the same County, Engincer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS," to be
as follows:-
This Invention has for its object improvements in the construction of
pistons.

page_text: In pistons of many descriptions at present in extensive use metallic
or other packing is employed in such manner as to require frequent
adjustment by screws or other means provided for that purpose, which
adjustment besides requiring great skill and extreme care must always
be more
or less uncertain and consequently unsatisfactory, as the
workman performing the operation under ordinary circumstances has
no reliable indication of the extent of compression of the packing.
The result often is that pistons are at first starting so tightly packed as
to cause great waste of power by friction, besides occasioning rapid
wear of the piston and cylinder, so that leakage quickly follows, thereby
necessitating the repacking of the piston at frequent intervals, an
operation which usually involves considerable expense and loss of time.
Now our Invention consists in a peculiar combination of devices for
obviating these scrious evils by causing the ring or rings of the piston
to press constantly against the inner surface of the cylinder with a force
which shall vary in proportion to the extent of variation between the
pressures on the respective sides of the piston, the packing being so
adjusted as to form a good but not unnecessarily tight joint at a
minimum pressure, to force the piston ring or rings more and more
tightly against the inner surface of the cylinder as thic pressure upon
the side of the piston increases, and to correspondingly reduce the
force with which the ring or rings so presses or press against the cylinder
in proportion as the pressure-against-the-piston's-side.diminishes.
According to our Invention the block or body of the piston is formed
with small holes or passages; the number of which may be varied to
suit the size of the piston, and these small holes or passages are fitted
with corresponding small pistons properly packed and capable of moving
therein when influenced by any excess of pressure at one side of the
piston over that at the other side. The apparatus is so arranged that
in the normal position of these small pistons, that is, when there is au
equal pressure on both sides of the main piston, the latter will lie
perfectly easy within the cylinder, but, that any change in pressure on
the respective sides of the piston will cause the small pistons to move
endwise within their respective holes or passages in the block or body
of the main piston, and such movement of the small pistons will be
communicated from them through the cap, top plate, or junk ring of the
main piston or through suitable feathers, T pieces, or equivalent devices
'

page_text: to the packing ring or rings so as to force the latter against the inner
surface of the cylinder.
In constructing pistons according to our Invention for single-acting
condensing engines, we prefer to bevil both edges of the packing ring,
and to interpose a second ring (bevilled at its under edge) between it and
the top plate, cap, or junk ring, which is connected to the small pistons
by means of small bolts or otherwise.
In pistons for double-acting or high-pressure engines the top plate,
cap, or junk ring is fixed, and the small pistons pass through it, the
block or body of the piston being formed to receive small feathers, T pieces,
or equivalent devices actuated by the small pistons so as to force the
packing ring or rings against the inner surface of the cylinder; or in
some cases, as for instance, in double-acting, condensing, pumping, or
marine engines, the moveable junk ring attached to the small pistons
and the feathers or equivalent devices for communicating motion from
the small pistons to the packing rings may be used in combination.
If desired india-rubber or other packing may some instances be
interposed between the top plate, cap, or junk ring and the packing
ring or rings.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Quick and John Sampson in the Great Seal
Patent Office on the 17th June 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOSEPH
QUICK, the younger, of Sumner Street, Southwark, in the County of
Surrey, Civil Engineer, and JOHN SAMPSON, of Battersea Park, in the
same County, Engineer, send greeting.
WHEREAS Her most Excellent. Majesty Queen Victoria, by: Her
Letters 'Patent, bearing date the Seventeenth day of December, in:ithe
year of our Lord One. thousand eight hundred and sixty-eight in the
thirty-second year of Her reign, did, for. Herself, Her.. heirs and
successors, give and grant. unto us, the said Joseph Quick and John
Sampson, Her special licence that. we, the said Joseph Quick and
John Sampson, our executors, administrators, and assigns, or such.
others as. we, the said Joseph Quick and John Sampson, our

page_text: tors, 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
THE CONSTRUCTION OF PISTONS," upon the condition (amongst others) that
we, the said Joseph Quick and Jolin Sampson, our executors or adminis-
trators, by an instrument in writing under our or their hands and
seals, or under the hand and seal of one of us or them, 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 Scal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Joseph Quick, on behalf of myself
and the said Jolin Sampson, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement
thereof (that is to say):-
This Invention-has-for-its-object-improvements-in-the-construction of
pistons:
In pistons of many descriptions at present in extensive use metallic or
other packing is omployed, and frequently in such manner as often to
require adjustment by screws or other means provided for that purpose,
which adjustment besides requiring great skill and extreme care must
always be more or less uncertain, and consequently unsatisfactory, as
the workman performing the operation under ordinary circumstances has
no reliable indication of the extent of compression of the packing. The
result often is that pistons are at first starting so tightly packed as to
cause great waste of power by friction, besides occasioning rapid wear
of the piston and cylinder, so that leakage quickly follows, thereby
necessitating the repacking of the piston at frequent intervals, an
operation which usually involves considerable expense and loss of time.
Now our Invention consists in peculiar devices for obviating these
serious evils by causing the ring or rings of the piston to press con-
stantly against the inner surface of the cylinder with a force which shall
vary in proportion to the extent of variation between the pressures on
the respective sides of the piston, the packing being so adjusted as to

page_text: form a good but not unnecessarily tight joint at a minimum pressure to
force the piston ring or rings more and more tightly against the inner
surface of the cylinder as the pressure upon the side of the. piston
increases,, and. to correspondingly reduce the force with which the ring
or rings so presses or press against the cylinder in proportion as the
pressure against the piston's side diminishes, and we attain these results
without the direct action of the steam or. other. actuating fluid behind
the packing rings..
According to our Invention the block or body of the piston is formed
with small holes or passages, the number of which may be varied to suit
tlic size of the piston, and these small holes or passages are fitted with
corresponding small pistons properly packed and capable of moving
therein when influenced by any excess of pressure at one side of the
piston over that at the other side. The apparatus is so arranged that in
the normal position of these small.pistons, that is, when there is an equal
pressure on both sides of the main piston,. the latter will lie or move
perfectly easy within the cylinder, but that any change in pressure on
the respective sides of the piston will cause the small pistons to move
endwise within their respective holes or passages in the block or body of
the main piston, and such movement of the small pistons will be com-
municated from them through the cap, top plate, or junk ring of the
main. piston, or through suitable T pieces or equivalent devices to the
packing ring or rings, so as to force the.latter against the inner surface
of the cylinder..
In constructing pistons according to our Invention for single-acting.
condensing engines we prefer to bevil both edges of the packing ring,
and to interpose a second ring (bevilled at its under edge) between.it
and the top plate, cap; or junk ring; which is connecteds to the small
pistons by means of small bolts or otherwise. In pistons for double-
acting or high-pressure engines the top plate, cap, or junk ring is fixed.
aud the small pistons pass through it, the block or body of the piston
being formed to receive small T pieces or equivalent devices actuated by
the small pistons, so as to force the packing ring or rings against the
inner surface of the cylinder; or in some cases, as, for instance, in
double-acting, condensing, pumping, or marine engines, the movable
junk ring attached to the small pistons and the T pieces or equivalent
devices for communicating motion from the small pistons to the packing.

page_text: rings may be used in combination. If desired india-rubber or other
packing may in some instances be interposed between the top plate, cap,
or junk ring and the packing ring or rings.
DESCRIPTION OF THE DRAWINGS.
The same letters of reference are used to denote corresponding parts
in all the views.
On Sheet 1 our Invention is shewn as applied to the piston of a
single-acting condensing engine, the cylinder being about 55 inches
in diameter.
Fig. 1 is a plan of the piston drawn to a scale of three inches to a
foot; Fig. 2, a transverse section through the line A, B, of Fig. 1;
Fig. 3, a full-size cross section of part of the block or body of the piston
and junk ring with the packing ring and intermediate ring in position;
and Fig. 4, a reduced view of parts of the intermediate ring and the
packing ring showing their slits.
a is the block or body of the piston; it is formed with three holes or
passages a', which are provided with gun-metal linings as to receive the
small pistons 6 which work therein, and are made to fit accurately by
means of packing springs 6'. The pistons 6 are connected to the junk
ring c by small rods or bolts d, as shown. The packing recess formed in
the block a is in this case furnished with a gun-metal facing a³, in order
to increase the durability of the piston, but in cases where a reduction in
first cost is important this facing may be dispensed with.
e is the gun-
metal packing ring, whose edges are bevilled, and f is the intermediate
ring having only its lower edge bevilled. The bevilled surfaces of the
rings e and fand facing a³ should be ground so as to fit one another
accurately. Any excess of pressure on the upper side of the piston has
the effect of causing the junk ring c to press against the intermediate
ring f, thereby forcing the bevilled packing ring e against the inner
surface of the cylinder by compressing it between the bevilled surfaces
of the block a and intermediate ring f.
.:
On Sheet 2 of the Drawings our Invention is illustrated as applied to
the pistons of locomotives and other high-pressure double-acting engines,

page_text: Fig. 5 representing a plan view of the piston, partly in section, and
Fig. 6 a transverse section thereof thro' the line C, D, of Fig. 5.
a is the block or body of the piston; it is made with four holes or
passages a fitted with corresponding pistons b; these pistons pass
through suitable holes formed for that purpose in the cap or junk
ring c, which is in this case fixed to the block or body a of the piston
by means of bolts c³, as shewn; e, e', are the packing rings. They are
kept pressed against the interior of the cylinder by means of the
T pieces g which are fitted into the block a; the ends g¹ of these
T pieces pass through holes a' in the block a, and are let into recesses
in the sides of the small pistons b. These recesses must be of sufficient
size to allow for the necessary motion of the T pieces when actuated
by the movement of the small pistons, and for the same reason the
It will be
edges g, g, of the T pieces should be slightly bevilled.
evident that when the pressure of the steam is on the upper side the
small pistons will act against the ends g¹ of the T pieces, and cause
their edges to describe the arc of a circle whose centre is at x, as
shewn dotted in red, and thus to force the lower packing ring e' against
the interior of the cylinder, and that when the pressure is on the under
side the edges g³ of the T pieces will be caused in like manner to
describe the arc of a circle having its centro at a³, so as in turn to force
the upper packing ring e against the interior of the cylinder to form
the joint.
Fig. 7 is a cross section of part of a piston resembling the foregoing
in its action, but specially designed to prevent any jarring of the parts
at very high pressures. In this case instead of forming the small
pistons with recesses to receive the ends g¹ of the T pieces, we employ
two separate small cup-shaped pistons to each T piece, one of such
pistons being situated at the lower side and the other at the upper side
of the end g¹ of the T piecc. These separate cup-shaped pistons are
kept up to the ends of the T picces by means of spiral springs h, as
shewn. It may in some cases be found convenient to employ a.com-
bination of solid and cup-shaped pistons acting directly upon the junk
rings of the main pistons..
On Sheet 3, Fig. 8 is a plan view, partly in section, and Fig. 9 a cross
section shewing our Invention as applied with very satisfactory results
to a direct-acting pumping engine having pistons about 70 inches in

page_text: diameter, and working at an average steam pressure of about 20 pounds
per square inch.
This arrangement may also be applied with great
advantage to double-acting, condensing, pumping, or marine engines.
a is the block of the piston; it is formed with four holes suitably lined
with gun metal to receive the four small pistons b, which are connected
by rods or bolts d to the junk ring c, as shewn. The block a is further-
more formed to receive T pieces whose ends g' take into recesses
formed in the sides of the small pistons b. When the pressure of the
steam is on the under side the small pistons b act against the ends g' of
the T pieces, and cause their edges to describe the arc of a circle, as
shewn dotted in red, and so to force the packing ring e against the
interior of the cylinder, but when (in double-acting engines) the steam
pressure is against the upper part of the piston then the junk ring c
presses against the intermediate ring f, so that the bevilled packing
ring e is forced against the interior of the cylinder by being compressed
between-the bevillod-surfaces of the block a and intermediate ring f
On Sheet 4, Fig. 10 is a plan view, and Fig. 11 a cross section showing:
an arrangement of piston similar in its main features to that represented
on Sheet 1, but modified for the interposition of india-rubber-or-other
packing, as shewn at i, between the junk ring-c-and-the-packing
ring e.
And having now described the nature of our said Invention, and in
what manner the same is to be performed, we would have it distinctly
understood that we do not confine or limit ourselves to the precise
arrangements described and illustrated in the accompanying Drawings,
as the same admit of being variously modified to suit the requirements
of particular cases without departing from the distinctive features of our
Invention, with reference to which we claim,-
1st. The use and application of small pistons or surfaces 6 for actuating
the packing ring or rings, and causing it or them to press against the
interior of the cylinder with a force varying in proportion to the pressure
on the side of the main piston.
2nd. The means for transmitting motion from the pistons b to the
packing rings e, substantially as shewn on and described with reference
to Sheets 1 and 4 of the accompanying Drawings.

page_text: 3rd. The use or employment of the T pieces g, or their equivalents, in
combination with the pistons 6 and packing rings e, substantially as
described for the purposes specified.
4th. The combination and arrangement of devices whereby motion is
transmitted from the pistons b to the packing ring e, substantially as
shewn on and described with reference to Sheet 3 of the accompanying
Drawings.
In witness whereof, I, the said Joseph Quick, the younger, have
hercunto set my hand and seal, this Sixteenth day of June, in
the year of our Lord One thousand eight hundred and sixty-
nine.
JOSEPH QUICK, JUN. (L.S.)
Witness,
J. E. MAYNE,
Clerk to F. Wise & Co.,
Patent Agents,
.Buckingham St., Adelphi, W.C.