IMPROVEMENTS IN SPRINGS FOR RAILROAD CARS AND FOR OTHER PURPOSES
Year: 1859

page_text: ..LETTERS PATENT to John Talbot Pitman, of the American and European
Patent Offices, No. 67, Gracechurch Street, London, for the Invention of
"IMPROVEMENTS IN SPRINGS FOR RAILROAD CARS AND FOR OTHER PURPOSES."
-A communication from abroad, by John J. Fields, of Brooklyn, in the
Sealed the 22nd September 1859, and dated the 22nd March 1859.
PROVISIONAL SPECIFICATION left by the said John Talbot Pitman at
the Office of the Commissioners of Patents, with his Petition, on the
22nd March 1859.
1, JOHN TALBOT PITMAN, of the American and European Patent Offices,
No. 67, Gracechurch Street, London, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SPRINGS FOR RAILROAD CARS AND FOR OTHER
PURPOSES," a communication from John J. Fields, of Brooklyn, in the State of
New York, one of the United States of America, to be as follows:-
In forming the elastic substance, composing the spring, into a single hollow
cone or series of cones fitting one within the other. This brings into requisi-
tion more surface in proportion to the quantity of material, and thereby
developes more elasticity, and creates greater resistance and action than by
other modes of construction. The single cone, or the exterior one or sheath of
the series, is fitted into a metallic campanulate housing, having a thickness
from interior to exterior surface of about an inch. Its apex may be ter-
minated like that of a truncated cone with rounded edges; to its base a rim or

page_text: flange of greater thickness may be attached, the upper and lower surfaces of
which are flat, parallel with each other, and perpendicular to the base. Into
the cavity of the sheath a coniform plunger or core plug is fitted, with a flange
also to rest on that of the sheath, having its under surface concave or dished.
This plunger may be solid, or may have a conical cavity for the reception of a
secondary hollow cone sheath, constructed similarly to the first, and a solid
core plug may be fitted into the cavity of this last, with a dish head or rim
concave or dished beneath, like the first plunger.
Also in the use and construction of two metallic cup-like receptacles formed
to receive, confine, and protect the spring. One of these housings may have
its interior walls for the first third of its depth slightly inclining, to which
succeeds an abrupt bulgo or ledge to receive & support the rim of the sheath,
and for the remaining distance the incline will be greater until the walls
approach the bottom, when they may expand & terminate on a plane like the
walls of a bell. The other housing used in connection with the first is formed
to receive the butt end of the spring, and is intended to be so adjusted that by
the weight or pressure one may overlap the other, and thus form a complete
metallic housing.
Various modifications may be substituted for the above, all of which I
consider as part of my Invention as long as the conical surface of the spring is
supported and acted upon vertically, laterally, & obliquely by the action or
resistance of the conical sides of the cup, creating an equalization of the elastic
force, and a regular diffusion of pressure & compression throughout the entire
substance, and instead of diminishing or destroying the clastic energy, increasing
it by engendering a self-sustaining principle by forcing towards a centre the
sloping surfaces of the spring.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Talbot Pitman in the Great Seal Patent Office on
the 22nd September 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN S
TALBOT PITMAN, of the American and European Patent Offices, No. 67,
Gracechurch Street, London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-second day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the
year of
Her reigu, did, for Herself, Her heirs and successors, give and grant unto

page_text: me, the said John Talbot Pitman, Her special licence that I, the said
John Talbot Pitman, my executors, administrators, and assigns, or such
others as I, the said John Talbot Pitman, or my executors, adminis-
trators, 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 SPRINGS FOR RAILROAD CARS AND FOR OTHER
PURPOSES," a communication from abroad, by John J. Fields, of Brooklyn,
in the State of New York, one of the United States of America, upon the
condition (amongst others) that I, the said John Talbot Pitman, 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 John Talbot Pitman, 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 statement, reference being had to the Drawings hereto annexed
as part of this Specification.
Figure 1 represents one form of the spring complete, detached from the
pedestal of the car frame with single housings; Figure 2, a vertical section of
same; Figure 3, the cup-like receptacle housing; Figures 4 & 8, the hollow
elastic cone or sheath part; Figure 5, the inverted cone plunger or core part;
Figure 6, the secondary cone sheath; Figure 7, a secondary inverted cone
plunger or solid core part; Figure 9, the cup housing; Figure 10, cover
housing; Figure 11, completo housing, with the cone spring within. The
same letters indicate the same or similar parts in all the Figures.
The nature of my improvements consists, first, in forming the elastic
substance composing the spring into a single hollow cone, or series of cones
fitting one within the other, for the purpose of presenting more surface in
proportion to the quantity of material than when used solid, and thereby to
develope more elasticity, and create greater resistance and action than by other
forms of construction.
The single cone, or the exterior one or sheath f. f, of the series, is fitted for
a metallic campanulate housing a, a, a, or a pair of housings, Fig. 11, having
a. thickness from interior to exterior surface of about an inch. Its.apex c, e,;

page_text: may be terminated like that of a truncated cone with rounded edges. To its
base a rim or flange 9, 9, 9, is attached, of greater thickness; . the upper and
lower surfaces of the rim are flat, parallel with each other, and perpendicular
to the base. Into the cavity of the sheath a coniform plunger. or core
plug h, h, h, Fig. 5, is fitted, with a flange also, to rest on that of the sheath,
with its under surface i, i, concave or dished. This plunger may be solid or
may have a conical cavity J, J, for the reception of a secondary hollow cone
sheath, Fig. 6, with an annular rim L, L, L, constructed like the first.f, and
a solid core plug k, k, Fig. 7, with a disk head or rim o, o, concave or dished
beneath, like i, i.
Second, in the use and construction of two metallic cup-like receptacles
formed to receive, confine, and protect the spring; one of these a, a, Fig. 1
and Figure 8, may have its interior walls b, b, for the first third of its depth
slightly inclining, succeeded by a ledge or abrupt bulge c, c, to receive and
support the rim g, g, of the sheath f, and then a greater incline d, d, until the
walls approach the bottom, when they may expand and terminate on a plane e, e;
like the walls of a bell. This may be used singly or in conjunction with
another formed to receive the other or but end of the spring, Fig. 10. These
are adjusted so that by the weight or pressure they may come together or
overlap, and thus form a complete metallic housing, Fig. 10. In the applica-
tion of theso springs they may be used reversed or inverted, but for the
protection of the lower one and its housing I attach short legs p, p, to tho
housing, to keep it from the axle of the car. When the pressure is upon
the cap of the upper housing, the cone f is more or less depressed, and the
compression of the elastic substance commences at the apex and continues to
increase upwardly and to distend outwardly or laterally as the downward
pressure increases, and when the weight suffices the upper cap or housing
closes over the lower housing, or vice versâ, an inch or so, in which case the
elastic cone is compressed downwardly and expanded laterally, so as to fill up
the interior space or cavity of the lower housing, and is thus well supported
and made secure by its surroundings; at the same time it is protected from
injury. The peculiar formation of my spring effects an equalization of pressure
and compression, whereby the superincumbent weight or force applied thereon
bears regularly throughout the whole elastic surface employed, vertically,
laterally, and obliquely, diffusing throughout the elastic volume any force or
strain acting thereon.
It not unfrequently occurs that under great pressure the elastic mass, in the
usual form of springs, gives way, and the action of the spring is destroyed;
and where thick masses of rubber are used, that a great portion thereof must

page_text: possess considerable immobility or non-active property, so that the central part
of the spring cannot give out any elastic action, and remains inert, hence there
is more or less loss of the inherent elastic property; when this is the case
there must ensue a more or less irregular rebound and vibratory action, causing
an undulatory motion to the car, owing to the inequality of the two forces,
pressure and compression. By using the elastic substance in the form of a
hollow elastic cone or sheath, about two-thirds of the material usually required
is dispensed with, while I place in position for developement an equal amount
of active elastic property, and by the employment of metallic housings, and the
upward action of the sloping sides of the socket pressing against the oblique or
conical surface of the core, too much lateral expansion is avoided; and while
every particle of the substance thereof is equally supported, equalization of
elastic force and regular diffusion and compression are produced throughout.
Various modifications may be substituted for the above, all of which
I consider as part of my Invention as long as the conical surface of the spring
is supported and acted upon vertically, laterally, and obliquely by the action
or resistance of the conical sides of the cup, creating an equalization of the
elastic force, and a regular diffusion of pressure and compression throughout
the entire substance, and instead of diminishing or destroying the clastic
energy, increasing it by engendering a self-sustaining principle by forcing
towards a centre the sloping surface of the spring.
Having now described the nature of my Invention, and the manner in
which it is performed, what I claim, and desire to secure under the herein-
before in part recited Letters Patent, is, the form of constructing the elastic
substance into single or combined cone springs, as herein set forth, and in
employing them in combination with the single or combined metallic housings,
substantially as described.
In witness whercof, I, the said John Talbot Pitman, have hereunto set
my hand and seal, on this Twenty-first day of September, A.D. One
thousand eight hundred and fifty-nine.
JOHN TALBOT PITMAN. (L.S.)