IMPROVED PACKINGS FOR PISTONS AND STUFFING BOXES, APPLICABLE ALSO FOR THE PURPOSES OF A VALVE
Year: 1879

page_text: "
LETTERS PATENT to Alexander Melville Clark, of Chancery Lane, in tho
County of Middlesex, Patent Agent, for the Invention of IMPROVED
PACKINGS FOR PISTONS AND STUFFING BOXES, APPLICABLE ALSO FOR THE
PURPOSES OF A VALVE." A communication from abroad by Aloha Vivarttas,
Mark Kerr Hamilton, junior, George Sears Greene, junior, Willard Atheton
Nichols, Charles Heyward Myers, and William Walter Maclay, all of New
York City, in the United States of America
Sealed the 18th April 1879, and dated the 4th February 1879.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 4th February 1879.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVED PACKINGS FOR PISTONS AND STUFFING BOXES, APPLI-
CABLE ALSO FOR THE PURPOSES OF A VALVE." [A communication from abroad by
Aloha Vivarttas, Mark Kerr Hamilton, junior, George Sears Greene, junior, Willard'
Atbeton Nichols, Charles Heyward Myers, and William Walter Maclay, all of New
York City, in the United States of America.]
This Invention relates to packings for pistons, stuffing boxes, and in other cases
where a tight joint is required between parts moving one upon the other.
The Invention consists of an elastic packing having three portions arranged as
follows-1st, a straight or cylindrical spiral made to close by its own elasticity
upon the piston rod (or between the heads of the piston), following and fitting its
surface, however unequal from wear or other causes, without leak or excess of fric-
tion; 2nd, a straight spiral made to expand by its own elasticity and fill the stuffing
box or cylinder, making a tight joint under the saine variable conditions; and, 3rd,
an intermediate tapered or conical spiral portion which connects the first and second-
parts, permitting by its elasticity and the flexibility of its coils in sliding upon each
other the friction of motion required by said first and second parts independently of:
each other, and without causing such a separation of the parts as shall permit.
leakage in any place. It is obvious that this packing may be made of one or more:
springs, and that the section of the springs may be varied without affecting the
general points mentioned.

page_text: This packing may be made of some material having very little friction, as soft
metal, and the first and second parts re-enforced by exterior and interior springs of
steel or other very elastic material; or the packing may be made of a single sub-
-stantial-and-durable spring, armed, the first part interiorly and the second part
exteriorly, with soft or frictionless material, while in either case the intermediate
part will need no re-enforcing, as the pressure of the steam tends to keep the coils
closed-one upon the other. By inserting in the conical intermediate part à flat ring
or washer the first and second_parts_may_ be returned-upon-one-another-in cases
=where economy of space is a desideratum.
This also may be either re-enforced. or armed as described, and the three portions
may be secured together or made separate and independent of each other. All of
the joints will be kept tight by the pressure, without affecting the action of the
parts, as described.
This packing may be made of any suitable material, and in some one of its forms
may be applied to any case where a movable rod or connection is required to be
packed, as rods of pistons, valves, water gates, pumps, or in chemical manipulations,
for which latter case the stuffing box, rod, and packing may be all made of glass or
earthenware. A packing of this kind of suitable proportions will operate as a valve,
opening to permit the passage of liquids or fluids in one direction through the
conical intermediate part, and closing by pressure in the contrary direction, and
when attached to the piston rod, as of a pump, constitutes a combined piston and
valve. A packing of this kind of suitable proportions secured to the piston rod will
make a piston of variable diameter, fitting and working smoothly, and without
leakage in a tapered cylinder, or conversely on a tapered rod.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the 30th
July 1879.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent.
"IMPROVED PACKINGS FOR PISTONS AND STUFFING BOXES, APPLI-
CABLE ALSO FOR THE PURPOSES OF A VALVE." A communication from abroad by
Aloha Vivarttas, Mark Kerr Hamilton, junior, George Sears Greene, junior, Willard
Atheton Nichols, Charles Heyward Myers, and William Walter Maclay, all of New
York City, in the United States of America.
This Invention relates to packings for pistons and stuffing boxes, and applicable
also in other cases where a tight joint is required between parts moving one upon
the other.
The Invention is illustrated in the accompanying Drawings, in which Figure 1 is
a sectional view of the stuffing box of a steam cylinder with a part of the piston
rod, and showing the packing in position; Figure 2 is a sectional view of the
stuffing box of a steam cylinder with a part of the piston rod, and showing the
packing also in section; Figure 3 is an end view of the packing; Figure 4 is a

page_text: sectional view of a portion of a steam cylinder, showing. the arrangement of the
packing for a double acting piston; Figure 5 is a sectional view of another form of
packing; Figure 6 is a sectional view of a packing, showing the method of re-
inforcing the same; Figure 7 is a sectional view of the packing, showing a
method of arming the same; Figure 8 is a sectional view of another form of the
packing.
This Invention consists of an elastic packing A having three portions arranged as
follows: 1st, a straight or cylindrical spiral B made to close by its own elasticity
upon the piston rod Ě (or between the heads of the piston H, Figure 4), following
and fitting its surface, however unequal from wear or other causes, without leak or
excess of friction; 2nd, a straight spiral C made to expand by its own elasticity
and fill the stuffing box F or cylinder F¹, making a tight joint under the same
variable conditions; and, 3rd, an intermediate tapered or conical spiral portion D,
which connects the parts B and C, permitting by its elasticity and the flexibility of
its coils in sliding upon each other the freedom of motion required by the parts B
and C independently of each other, and without causing such a separation of the
parts as shall permit leakage in any place.
It is obvious that this packing may be inade of one or more springs, and that the
section of the springs may be varied, as shown in Figure 5, or otherwise, without
affecting the general points mentioned.'
This packing may be made of some material having very little friction, as soft
metal, and the part B reinforced by an internal spring c, as shown in Figure 6; or
the packing may be made of a substantial and durable spring B, C, D, armed in B
and upon C with soft or frictionless material, as b' or c¹, as shown in Figure 7, while
in either case the part D will need no reinforcing, as the pressure of the steam in
the direction of the arrow G tends to keep the coils closed one upon the other..
Another form of this packing is shown in Figure 8, where by inserting in the conical
part D a flat ring or washer d, the parts B and C may be returned upon one another
in cases where economy of space is a desideratum. This also may be either re-
inforced or armed as described, and also the three portions B, C, and D may be
secured together or made separate and independent of each other, the direction of
the pressure being shown by the arrow. All of the joints will be kept tight by the
pressure, without affecting the action of the parts, as described.
This packing may be made of any suitable material, and in some one of its forms
may be applied to any case where a moveable rod or connection is required to be
packed, as rods of pistons, valves, water gates, pumps, or in chemical manipulations,
for which latter case the stuffing box, rod, and packing may be all made of glass or
earthenware.
A packing of this kind of suitable proportions will operate as a valve opening to
permit the passage of liquids or fluid in one direction through the part D, and
closing by preference in the contrary direction, and when attached to the piston rod,
as of a pump, constitutes a combined piston and valve. A packing of this kind of
suitable proportions secured to the piston rod will make a piston of variable
diameter, fitting and working smoothly, and without leakage in a tapered cylinder,
or conversely on a tapered rod.
The ordinary kinds of packing, where the substance being wound around the
piston rod is forced into the stuffing box by the gland or follower, are open to the
objection that they have no gauge or means of knowing how much pressure is being
exerted upon the rod, and are often a cause of great waste of power, or, in other
words, fuel, to overcome a friction many times in excess of what is necessary to
make a tight joint. Thus engineers by a turn or two more than is needed upon the
screws of the stuffing box really cripple the engine by applying what is practically
a very powerful brake. This is a common trouble. Also, a piston rod naturally
wears most rapidly in the middle portion of its length, and a packing of the ordinary
kind that is just fitted to be tight, that is, without leak upon the centre of the rod,
is unnecessarily tight at the ends thereof, acting as a brake applied at each end of
the stroke, causing both loss of power and irregularity of motion; or, if the packing

page_text: be fitted to the ends of the rod, it leaks when upon the centre of it, while with the
packing herein described the engineer cannot by any inadvertence increase the
friction, and differences in the diameter of a worn rod are accounted for in
the elasticity of the packing, and cannot be felt, thus completely obviating the
difficulties mentioned.
Having described the nature of the said-Invention, and the manner of performing
the same, I declare that-what-I-claim-as the Invention to be protected by the
hereinafter in part recited Letters-Patent is,
1. The packing A, composed of two parts, either of which may be radially con
tracted or expanded independently of the other, as and for the purposes described.
2. The packing A, consisting of the parts B and C, combined with the tapered
spiral D, as described, when the convolutions of D by overlapping form between
themselves a tight or impervious joint, substantially as herein shown and set
forth,
3. The packing À, consisting of the spirals B and C, as heroin shown and
described.
4. The combination with the packing A, constructed as shown, of the reinforce-
ment c or b, as and for the purposes set forth.
5. The combination with the packing A, constructed as shown, of the arming c¹
or b¹, as and for the purposes set forth.
6. The combination of the packing A, as described, with the stuffing böx F and
rod E, substantially as herein shown and described.
7. The combination of the packing A, as described, with the cylinder F¹ and piston-
rod E, substantially as herein shown and described.
8. The combination of the packing A, as described, with the plate d, substantially
as herein shown and described.
9. The packing A, having the parts B and C, combined with the tapered spiral
D, as described, when by the elasticity and flexibility of D the necessary freedom of
motion is permitted to the parts B and C, as herein shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Twenty ninth day of July, in the year of our Lord
One thousand eight hundred and seventy nine.
CLADD