IMPROVEMENTS IN THE CONSTRUCTION OF RAILWAY AND OTHER WHEELS
Year: 1873

page_text: LETTERS PATENT to Henry Hahn, of 27, Lombard Street, in the City
of London, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION
OF RAILWAY AND OTHER WHEELS."-A communication from abroad
hy Wilhelm Basson. Civil Engineer of St. Petersburgh. Russia.
I, HENRY HAHN, of 27, Lombard Street, in the City of London, do
hereby declare the nature of the said Invention for “IMPROVEMENTS IN
THE CONSTRUCTION OF RAILWAY AND OTHER WHEELS," to be as follows:-
This Invention relates to improvements in the construction of wheels
for railway and other purposes, being made by the combination of two
flanged plates or discs, which are by preference rolled and pressed into
shape, and screwed one into the other at the nave, or otherwise com-
bined, the outer flanges being so pressed together that they form but
one solid wheel circumference after they have cooled down and con,

page_text: tracted. The tyre being shrunk on at a high temperature fits tightly
thereon, and the curvature of the plates or discs thus combined imparts
great elasticity to the whole circumference of the wheel, expanding and
contracting readily with any change of temperature, the blows and
shocks to which it may be subjected being distributed at once through the
entire circumference and structure of the wheel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Hahn in the Great Seal Patent Office on
the 27th November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
HAHN, of 27, Lombard Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of May, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Henry Hahn, Her special
license that I, the said Henry Hahn, my executors, administrators,
and assigns, or such others as I, the said Henry Hahn, my executors, a
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 RAILWAY AND OTHER WHEELS," a communication to me
from abroad by Wilhelm Basson, Civil Engineer, of St. Petersburgh,
Russia, upon the condition (amongst others) that I, the said Henry
Hahn, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should par-3
ticularly 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,

page_text: When the plate or disc a has assumed the form represented in section
in Figure 3 it is placed on the table or support 6 mounted on the upper
end of the hydraulic ram c of the hydraulic press, shown in section by
Figure 3. The ram c is caused to force the plate a up to and through
the circular opening formed in the head d of the press, by which a flange
is formed around the periphery of the plate or disc a, which is also thus
caused to assume the curved form of the upper surface of the table a.
The plates or discs a thus prepared are placed in suitable lathes in order
to turn the edges and nave, a male screw thread being cut in the nave
of one, and a corresponding female thread being cut in the nave of the
other of a pair of such plates, for the purpose of screwing the two naves
together as represented in section Figure 4 of the Drawings hereunto
annexed.
In order to screw the two plates or discs together, the disc having
the largest circumference is heated to cause it to expand, it is then
screwed on to the smaller disc at the nave, causing the flange of the
heated disc to overlap the outer circumference of the smaller disc upon
which it contracts as it cools, so that the two discs thus combined form
one solid clear-sounding hollow disc, as represented in section at Figures
5 and 6.
The tyre of the wheel is heated and shrunk on to the wheel in the
ordinary manner, as is well understood, but with a little more tension.
The hole for the axles having been turned in the naves, the wheels are
pressed on to the axles by means of a common hydraulic press with
standards and gauge.
Wheels constructed in accordance with these improvements possess a
certain degree of elasticity, the circumference offering the same uniform
resistance throughout, the shocks to which they are subjected being
distributed throughout the whole circumference of the wheel, so that
there is no tendency for them to break at any particular point as is the
case with wheels formed with spokes and spaces between the rim and
the nave. They also expand and contract uniformly when exposed to
changes of temperature.
Having thus described the nature of the Invention communicated to
me by my foreign correspondent, and the manner in which the same is
performed or carried into practice, it should be clearly understood that
no claim is herein made for the machinery or means employed for con-

page_text: structing or manufacturing wheels in accordance with this Invention, as
the same may be considerably varied; but what I claim under the above
in part recited Letters Patent is, the improved construction of railway
and other wheels by the arrangement and combination of two metal
discs and naves forming a hollow chamber between the nave and cir-
cumference, substantially in the manner herein-before described and
shewn in the Drawings hereunto annexed.
In witness whereof, I, the said Henry Hahn, have hereunto set
my hand and seal, this Twenty-eigth day of October, in the
year of our Lord One thousand eight hundred and seventy-
three.
Witness,
J. G. TONGUE,
Patent Agent,
34, Southampton Buildings,
Chancery Lane.
W.C.
HENRY HAHN. (L.S.)