IMPROVEMENTS IN PISTON HEADS AND THEIR PACKING
Year: 1864

page_text: LETTERS PATENT to George Haseltine, of the "International Patent
Office," No. 12, Southampton Buildings, Chancery Lane, in the County
of Middlesex, Civil Engineer, for the Invention of "IMPROVEMENTS IN
PISTON HEADS AND THEIR PACKING."-A communication from abroad by
Henry Denison Dunbar, John Wesley Labaree, both of Hartland, Ver-
mont, and Hamilton Ela Towle, of New York City, all in the United
States of America.
PROVISIONAL SPECIFICATION left by the said George Haseltine at the
Office of the Commissioners of Patents, with his Petition, on the 8th
July 1864.
I, GEORGE HASELTINE, of the "International Patent Office," No. 12, South-
ampton Buildings, Chancery Lane, in the County of Middlesex, Civil Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN PISTON
HEADS AND THEIR PACKING," a communication, to be as follows:-
Segmental packing rings have heretofore been used on piston heads, and
the packing has been held out against the cylinder by steam and by springs,
but no provision has been made to entirely prevent the steam from passing
beyond the packing, so far as I am informed, and the object of my Invention
is to pack the joints by means of cut, uncut, and segmental rings held out by

page_text: variable pressure, without, however, a great amount of friction, and without
cutting the piston-head ring, which is formed solid.
These improvements relate, first, to combining with the solid piston-head
ring segmental packing rings breaking joints with each other, and one fitting
into an angle of the other; second, to the employment of a cut and uncut
packing ring combined, which rings are expanded by steam or other pressure
acting inside the cylinder, and may be constructed with the outside or wearing
surface either broader or of less breadth than the inside or pressure surface,
for the purpose of reducing the wear and friction on one side and graduating
the pressure at will on the other side, while a tight fit is obtained; third, to
the manner of covering the joint or joints in the expanding rings or segments
for the purpose of preventing any escape of steam. The ring upon the piston
head is uncut, and is formed with a shoulder upon one or both edges of its
exterior surface to receive the packing rings. The perimeter of this ring does
not necessarily work steam-tight against the cylinder, but in each of its
shoulders are placed two packing rings, both of which are cut into segments
so as to break joints with each other. One of these rings is made of an L or
angle iron form, and the other simply fits into the angle of the first, both
rings touching the interior surface of the cylinder. Behind these rings, but in
contact only with one, is placed a spring or springs for the purpose of holding
the rings in place when the steam or other pressure is removed. Steam or
other motive power employed is admitted behind the packing rings through
passages formed in either end of the piston head or in any other convenient
For the purpose of lessening the friction upon the interior surface
of the cylinder the surface of the packing rings in contact with the cylinder
may be made greater than the surface against which the outward pressure is
applied. In this case the rings are so arranged that the outward pressure
is exerted directly against both, and only the angle or L-shaped one comes in
contact with the interior surface of the cylinder. A second shoulder may be
cut on the piston-head ring sufficiently large to admit one part of the angle-
shaped ring to increase the surface of the packing ring in contact with the
cylinder. The L-shaped packing ring is cut, and has also a portion of the rim
cut away on both sides of the slot. The other ring is uncut, but has a portion
of its perimeter extended to fit into the cut away portion of the L-shaped
ring, and one end of the latter may be united to the former, the other end of
said ring being unconfined. By this arrangement the uncut ring resists a
portion of the pressure of the steam or other force employed, at the same time
decreasing the interior surface of the expanding ring and overlying the slot in
the latter, thereby preventing the steam from passing through said slot. The
manner.

page_text: relatively large exterior surface of the expanding ring which comes in contact
with the cylinder greatly diminishes the friction caused by the pressure against.
the interior surface of the said ring..
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed"
by the said George Haseltine in the Great Seal Patent Office on the
2nd January 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the "International Patent Office," No. 12, Southampton
Buildings, Chancery Lane, in the County of Middlesex, Civil Engineer, send
greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of July, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said George Haseltine, Her special license that I, the said George
Haseltine, my executors, administrators, and assigns, or such others as I, the
said George Haseltine, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and 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 "IMPROVE-
MENTS IN PISTON HEADS AND THEIR. PACKING," a communication, upon the
condition (amongst others) that I, the said George Haseltine, my executors or
administrators, by an instrument in writing under my hand and seal, or under
the hand and seal of one of 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 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 George Haseltine, 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, reference being had to the accompanying Sheet of Drawings making
a part of this Specification, in which Figure 1 is a view of a piston head and
rod, one half in elevation and the other half in longitudinal section, and also
the cylinder in section; Figure 2 is an end view of the piston head with the

page_text: end plate removed to show the interior; Figure 3 is a perspective view of the
body or hub of a piston with one end plate attached. Like letters refer to
corresponding parts in each of these Figures.
Segmental packing rings have heretofore been used on piston heads, and
the packing has been held out against the cylinder by steam and by springs,
but no provision has been made to entirely prevent the steam from passing
beyond the packing, so far as I am informed, and the object of my Invention
is to pack the joints by means of cut, uncut, and segmental rings, held out by
variable pressure, without, however, a great amount of friction, and without
cutting the piston-head ring, which is formed solid.
These improvements relate, first, to combining with the solid piston-head
ring segmental packing rings breaking joints with each other, and one fitting
into an angle of the other; second, to the employment of a cut and uncut
packing ring combined, which rings are expanded by steam or other pressure
acting inside the cylinder, and may be constructed with the outside or wearing
surface either broader or of less breadth than the outside or pressure surface
for the purpose of reducing the wear and friction on one side and graduating
the pressure at will on the other side, while a tight fit is obtained; third, to
the manner of covering the joint or joints in the expanding rings or segments
for the purpose of preventing any escape of steam.
A, Figure 1, is a piston rod, to which the hub, central portion, or head B
of the piston is securely attached. The solid or uncut piston-head ring T is
properly shouldered out to receive the packing rings L, R, L¹, R', and is
made to slip over the hub B; D is a cap plate that fits over the end of the
piston head, being held thereto by bolts and nuts or in any of the usual ways.
This cap has passages a, a, through it to admit the steam or other pressure
behind the packing rings at that end of the piston, and similar openings a¹, a¹,
are made through the other end of the piston head to let the steam, &c., in
behind the packing rings at that end. The piston-head ring T is in one piece
and of a "T" shaped form in cross section, and sets over and is supported in
its position by the arms B. The perimeter of this ring does not or need not
work steam-tight against the cylinder E, but in its angles are laid two rings
L and R, both of which are cut into segments so as to break joints with each
other. The ring L is made of an "L" or angle-iron form, and the other
ring R simply fits into the angle of the ring L. Behind these rings is placed a
spring S simply to hold the rings in place when the steam, &c., is shut off.
It will be perceived that there are packing rings on both sides of the solid
ring T, so that there is double security against any steam, &c., getting behind
the piston by passing the packed joint. One end or plate of the piston head

page_text: is represented as cast with or made a part of the hub and arms B. Both
ends may be made separate, like D, and be drawn and held up by a shoulder
on the piston rod and a nut on the end of the same, or by separate bolts
holding the two plates together.
It is clearly seen in Figures 1 and 3 how the steam, &c., gets in behind the
packing rings through the holes a, a, and a¹, a¹, to force them out against the
cylinder E. It can also pass in behind the packing rings through the slots o, o, o,
shown in Figure 1, but I prefer using the holes a, a¹, only. The springs S, S, to
the extent of their power, whatever that may be, act to press outward the
packing rings L, R, but the main force is applied by the steam itself. In a
locomotive on a descending grade, where the piston works by a momentum
of the engine or its load, the steam being shut off, the springs alone hold out
the packing rings. In cases where it is considered desirable to further reduce
the friction in the interior of the cylinder the cross section of the rings T, L, R,
is modified in such a manner that the exterior or rubbing surface in contact
with the cylinder is made greater than the interior surface which receives the
outward pressure of the steam, &c. This modification is shown in Figures 4,
5, and 6.
Figure 4 is a view of a piston head and rod with such an arrangement of
the rings, one half in elevation and the other half in longitudinal section, and
the cylinder, in which the rings are shown ready to apply or place upon the
hub and arms or body, shown in Figure 3 in perspective; Figure 5 is a per-
spective view of the rings arranged with a less pressure surface on the concave
interior than rubbing surface on the convex exterior of the rings which come
in contact with the cylinder; Figure 6 is a view of the rings L, R¹, detached
from Figure 5, better showing their construction and arrangement. Like
letters refer to corresponding parts in each of these Figures.
The packing ring L' is of an "L" form in its cross section, and is cut as
at e, Figure 5, and has a portion of its rim cut away at each side of the slot,
as seen at f. The ring R¹ is uncut, and has a portion of its perimeter, as at i,
extended so as to fit into the cut away portion f of the ring L', and one end
of the cut ring L' may be united to the uncut ring R', as at n, Figure 6, by
screw, rivet, or otherwise, the other end of the said ring being free. The
rings R', L', united and placed together as above described, pass over the
shoulders 1, 2, 3, of the solid ring T, Figure 5, and when the cap plate D',
Figure 4, is in place, cannot drop out of their proper positions. In the heads
or plates C', D', Figures 3 and 4, are openings or holes a', a', through which
steam may pass to force out the ring L' against the cylinder E, Figures 1
and 4, and thus pack the piston. It will be perceived that the steam surface

page_text: on the inside of the ring L' is rendered very small, whilst its rubbing surface
on the perimeter is quite extended. The object of this arrangement is that
the friction between the rings thus expanded by steam, &c., and the cylinder
shall be diminished whilst the rubbing surface shall be enlarged. The ring R',
which is uncut and occupies a portion of the interior of the ring L', it lying
under its flange, takes away a portion of the steam-bearing surface from the
ring L', whilst it overlies the cut in said ring L' and prevents the steam, &c.,
from passing through the cut. I have shown two sets of rings R, L, and
R', L', as connected to one piston, Figures 1 and 4, but a single set may be
used in large upright cylinders, and in such cases the solid ring T is dispensed
with. I propose to use these self-adjusting packing rings in steam, air, gas,
or water engines, including pumps.
Having thus fully described and ascertained the nature of this Invention,
as communicated to me from my foreign correspondent, I claim,-
First, the construction of piston heads and their packing by the combination
of a solid or uncut ring T with segmental or cut rings L, R, the latter fitting
into the angle of the former, and both breaking joint with each other; said
rings L, R, being held out by the action of the steam or other pressure in the
cylinder mainly to pack the piston, substantially as herein set forth.
Second, a combined cut and uncut packing ring or rings with the outside
or wearing surfaces broader than the inside or steam (or other pressure)
surface which the steam, gas, air, or water acts upon to expand, substantially
in the manner and for the purpose herein set forth.
Third, I also claim the combination of the projecting and cut away portions
of the rings R¹, L', for the purpose of breaking the joint in the expanding
ring, the two rings in this case being united and operating together, substan-
tially as herein set forth.
In witness whereof, I, the said George Haseltine, have hereunto set my
hand and seal, this Twenty-ninth day of November, in the year of
our Lord One thousand eight hundred and sixty-four.
Witness,
JOHN PRATT.
GEORGE HASELTINE. (L.s.)