Improvements in Pneumatic Tires.
Year: 1896

page_text: Date of Application, 15th May, 1896-Accepted, 19th Dec., 1896
COMPLETE SPECIFICATION.
Improvements in Pneumatic Tires.
We, HERMAN FERDINAND LANGE, residing at 608 O'Farrell Street, of
San Francisco, in the County of San Francisco, and State of California, U.S.A.
Merchant, and FERDINAND VON LEICHT, residing at 2010 Pierce Street, of
San Francisco, in the County of San Francisco, and State of California, U.S.A.
Mining Engineer, 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:-
Our invention relates to an improved construction of pneumatic tire for bicycles
whereby we seek to produce a light and elastic tire that cannot be punctured with
nails or sharp pointed obstacles on the roadway.
To such end our said invention consists, essentially in a pneumatic tire con-
structed of an inner inflatable rubber tube, an outer elastic tube of relatively large
diameter inclosing the air-inflated tube in which the last named tube is set and
fixed eccentrically and a body of fine saw-dust closely packed or compressed into
the crescent-shaped space between the said inflatable inner tube and the surrounding
elastic tube connected as hereinafter described and set forth, reference being had
in the following description to the accompanying drawing forming a part of this
specification, in which the figure represents in cross-section a portion of a pneumatic
tire constructed according to our invention a portion of the wooden rim of the
wheel also being shown.
The inner tube A is air-tight and is capable of forming a pneumatic tire.
The diameter of this tube when inflated should be about one inch. The outer
tube B also made of rubber or rubber fabric should be about twice the diameter of
the inner tube when so inflated and the inner tube being inserted into such outer
tube is laid in position eccentric to the surrounding tube and against the bottom
or lower side of the inner wall thereof, so that the crescent shape space between
the two tubes has its greatest breadth situated between the top of the inner tube
and the top of the outer tube that forms the tread or rim of the wheel. The two
tubes are united along their joint of contact by means of cement, or not, as may
be required and the usual inflating tube with check valve (not shown in the
drawing) to attach an air-pump fixed in the wooden rim X of the wheel and
through the body of both tubes into the inner tube.
The space between the two tubes A, B is closely packed with a body of fine dry
saw-dust, and after the ends of the tubes are joined and united to form the tire
the packing is compressed into a close dense body by inflating the inner tube.
The material for this packing C is best obtained from California redwood
lumber, which makes saw-dust of fine, dense and at the same time elastic quality,
and to increase such qualities we kiln-dry the packing material before using.
In proceeding to introduce this packing material we partially inflate the inner
tube and then pack the saw-dust as evenly as possible in the space between the
two tubes, and then unite the ends to complete the tire ready for the wheel. When
thus finished and placed around the rim of the wheel the inner tube is inflated to
its fullest extent to compress the saw-dust and bring the tire to the required
circular shape.
In our improved tire as thus constructed the air inflated tube which gives the
elastic quality to the tire is effectually protected from being cut or injured by

page_text: sharp obstacles lying in the path of the rider, and the life of such tire is thereby
greatly prolonged. But such advantage gained in and by such construction is not
at the expense of the lightness or the elasticity of the tire; for the air-tube is not
reduced in diameter to such an extent that the elastic property it gives to the tire
is affected by such reduction, and the complete protection obtained by the body of
saw-dust enables us to make the tubes of relative light or thin quality of rubber.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. The herein described pneumatic tire for bicycles consisting of an outer elastic
tube, an inner inflatable tube of much smaller diameter cemented to said outer
tube at a point remote from the tread, and a packing of saw-dust filling the space
between the two tubes, and surrounding the inner tube at all points except the
point of contact.
2. In a pneumatic tire for bicycles the combination of an outer elastic tube, an
inner tube secured to the inner face of the outer tube at a point diametrically
opposite to the tread of the latter, said inner tube having a lesser diameter than the
outer tube and being provided with means for inflation and a body of saw-dust
filling all space between the inner and outer tubes when the inner tube is inflated
and adapted to transmit pressure from the inner tube to the outer tube to cause
expansion of the latter.
Dated this 14th day of May 1896.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.