IMPROVEMENTS IN THE FIXING OF THE TYRES OF RAILWAY WHEELS, IN ORDER TO PREVENT THEIR COMING OFF IN CASE OF BREAKAGE
Year: 1877

page_text: LETTERS PATENT to Henry Conradi, of 8, Lower James Street, Golden Square,
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
FIXING OF THE TYRES OF RAILWAY WHEELS, IN ORDER TO PREVENT THEIR
COMING OFF IN CASE OF BREAKAGE." A communication from abroad by
Charles William Kesseler, Engineer, of Berlin, in Prussia, Germany.
PROVISIONAL SPECIFICATION left by the said Henry Conradi at the
Office of the Commissioners of Patents on the 22nd November 1877.
HENRY CONRADI, of 8, Lower James Street, Golden Square, in the County of
Middlesex. "IMPROVEMENTS IN THE FIXING OF THE TYRES OF RAILWAY WHEELS,
IN ORDER TO PREVENT THEIR COMING OFF IN CASE OF BREAKAGE." [A commu-
nication from abroad by Charles William Kesseler, Engineer, of Berlin, in Prussia,
Germany.]
The necessity of providing means against the coming off of the fragments of
the tyres from the wheels in case of breakage having been recognised, many
different designs have been worked out for a number of years.
The adjoining Drawing shows a new and improved method of fixing the tyres,
which gives an absolute security, and is so cheap that, I believe, nothing stands in
the way of its general adoption.
The tyre is internally turned, and is provided with a groove a, placed on the kew,
as shown in Fig. 1. The inner circle, upon which the the tyre is drawn by being
heated beforehand is turned accordingly, dovetailed in such a manner that on one
side (the left) the dovetail of the tyre takes that of the inner circle, while on the
other side (the right) this fastening is obtained by means of an inserted conical
wedge ring b, which is separately represented in Fig. 4. This ring is made smaller,
so that its largest diameter corresponds to that of the groove in the tyre, and is cut
through before it is inserted into the groove.
The ring can also be manufactured in such a manner, that it corresponds to the
largest diameter, and in order to be able to insert it, a piece can be cut off. After

page_text: being inserted, the ring has an opening of about 3 centimetres (1·1811 inch). This
opening is filled up with a separate wedge, as shown in Fig. 3. The ring is inserted
when the tyre is warm, and the inner circle is then firmly secured by the
inserted ring and through the contraction of the tyre.
Should a greater contraction of the ring be required at once, or should the tyre
have become loose after a certain time of its use, the ring can be rammed even in a
cold state. This method of fixing differs from other methods by which the rings are
used, that the tyre itself is not riveted on, avoiding therefore the dangerous strains
in the fibres, which produce the breakage.
The improvements upon which the claims are based, consist, therefore, in the
fixing of the tyre by means of an inserted conical ring of wrought iron or steel,
which can also be turned and by providing the tyre with a conical groove for the
reception of the ring; the latter can also be replaced by corresponding single wedges
shaped into the required form.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Conradi in the Great Seal Patent Office on the 21st May
1878.
HENRY CONRADI, of 8, Lower James Street, Golden Square, in the County of
Middlesex. "IMPROVEMENTS IN THE FIXING OF THE TYRES OF RAILWAY WHEELS,
IN ORDER TO PREVENT THEIR COMING OFF IN CASE OF BREAKAGE."
A commu-
nication from abroad by Charles William Kesseler, Engineer, of Berlin, in Prussia,
Germany.
The necessity of preventing the coming off of the fragments of the tyres from the
wheels in case of breakage having been duly recognised, many different con-
structions have been put into practice during a number of years, which
did, more or less, answer the purpose, but without fulfilling completely all the
requirements.
The adjoined Drawing shows another, but improved, method of fixing the tyres,
which offers an absolute security, and is at the same time so cheap, that, I believe,
nothing stands in the way of its general adoption.
The tyre, as represented in Fig. 1, is internally turned out, and is provided with
a groove a, worked on the skew. The inner circle, upon which the tyre is drawn,
by being heated beforehand, is on both sides dovetail shaped, so that the dovetail
of the tyre takes on one side that of the inner circle; while on the other side, this
fastening is effected by means of an inserted conical wedge ring b. The insertion of
this wedge ring, as represented, can be made by preference on the right hand side,
and the other dovetailed groove on the left; but it is of no consequence which side
is chosen. The wedge ring is separately represented in Fig. 4. This wedge ring is
made accordingly smaller, so that its largest diameter corresponds to the diameter
of the groove of the tyre, and besides is cut through before its insertion into the
groove in order to facilitate it.

page_text: It can also be made to correspond to
into the groove a piece can be cut off.
the largest diameter, and for its insertion
After its insertion the ring is open to about
three centimeters, and this opening is again filled up with a separate wedge, as
shown in Fig. 3. The ring is inserted when the tyre is still hot or warm, and the
inner circle becomes then firmly secured and tightly drawn in by means of the
inserted ring and through the contraction of the tyre.
Should a greater contraction of the ring be required at once, or should the tyre
have become loose after a certain time of its use, the ring can be rammed, even in a
cold state. This method of fixing the tyres differs from other methods, by which
rings are also used, that the tyre itself is not riveted on, the riveting being
objectionable, as dangerous strains are produced in the fibres through it, helping,
if not producing the breakage.
The improvements upon which the claims are principally based, consists in the
fixing of the tyre by means of an inserted conical wedge ring of wrought iron or
steel, which can also be turned upon the lathe, and by working into the tyre a
conical groove for the reception of the ring; the ring can also be replaced by
corresponding single wedges, shaped in to the required form.
In witness whereof, I, the said Henry Conradi, have hereunto set my hand
and seal, this Fifteenth day of May, in the year of our Lord One thousand
eight hundred and seventy-eight.