Improvements in Pneumatic Tyres.
Year: 1897

page_text: Date of Application, 6th Dec., 1897-Accepted, 29th Jan., 1898
COMPLETE SPECIFICATION.
Improvements in Pneumatic Tyres.
I, GUSTAV HILLER, of Zittau (Saxony), Germany, Cycle Manufacturer, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
My invention relates to pneumatic tyres for bicycles and other vehicles and it
has for its object to provide a tyre, composed of an inner non-stretchable air tube
and of a cover, which can safely be put on a wooden rim. Heretofore this has
been impossible, as the ordinary tyre, when being inflated, exerts a powerful
side pressure upon the outer narrowed parts of the rim, which causes them to
break off. The employment of closed tyres, i.e. air tubes containing within their
walls a tubular restraining envelope of canvas or other suitable fabric, is objection-
able because of the difficulty one has in repairing them, when punctured or cut.
As the wooden rims do not carry grooves or hook-shaped recesses for holding
the accordingly shaped edges of a cover, as is the case with the metal rims, a
cover of the ordinary kind cannot be made use of in connection with a wooden.
rim. According to my invention I provide means to secure a cover on a plainly
hollowed out wooden rim, whereby no lateral pressure will be exerted upon the
outer narrowed parts of the rim, when the tyre is being expanded.
In order to make my invention more easily understood, I have illustrated it
on the accompanying sheet of drawing, which shows a cross section of the cover,
of the air tube and of the wooden rim. The air tube A is made of vulcanized
rubber with an inner lining of canvas or like fabric. The edges c & d overlap
each other and are cemented together, thereby causing a thickening at that part
(shown in closer lining in the drawing).
This thickened portion is still further strengthened by the edge of the outer
cover being cemented unto the edge d of the inner air tube.
In case of a puncture, the free portion of the cover is turned back, the air
tube is repaired and the cover placed around the air tube again.
The lining of canvas being non-stretchable, the greatest diameter x of the tyre
cannot be forced outwardly, when the empty tyre has assumed the dotted line
position and the tyre is now being inflated. It will under the pressure of the
entering air take the circular shape, when the thickened portion will be pressed
forward against the rim C in the direction of the arrow and act as a kind of jam-
ring.
This jam-ring exerts such a powerful pressure towards the centre of the rim C
that it will securely hold the interposed edge a of the cover against the rim, with-
out causing any side pressure.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
The combination of an inner air-tube A provided with a non-stretchable lining

page_text: of canvas or a like fabric, the overlapping ends c, d of which air tube form a
thickening, with an outer cover B, one edge of which is cemented to the afore-
said thickening, as and for the purpose specified.
Dated this 24th day of November 1897