Improvements in Pneumatic Tires
Year: 1897

page_text: Date of Application, 9th Nov., 1897-Accepted, 18th Dec.,
1897
COMPLETE SPECIFICATION.
“Improvements in Pneumatic Tires."
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I, A. BERTRAM SHAW of Medford in the County of Middlesex, State of
Massachusetts, United States of America, manufacturer, do hereby declare the
Gature 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:
This invention relates to improvements in pneumatic tires and more especially
to improvements in the construction of the inner air tube, whereby when the
tire is punctured it may be automatically scaled or closed, and the escape of the
air thereby prevented. The objects of my invention are to effectually produce
the desired result with as little increase of the weight of the tire or in the
expense of the construction as is possible and without lessening its resiliency;
to so incorporate a sealing material, for the purpose of thus preventing the escape
of air when the tire is punctured, that said material may be maintained in a sticky
state and in a permanently active condition; and to otherwise improve the tire
as will be fully understood by a further description of the invention.
The invention consists, in the employment of a layer of absorbent material,
preferably fibrous and permanently attached to the inner surface of the air tube,
said layer being saturated with any suitable sticky sealing compound. The
invention is carried out substantially as illustrated in the accompanying drawings,
wherein :
Fig. 1 represents a side clevation partly in section of the felly and pneumatic
tire of a wheel containing my invention.
Fig. 2 represents a cross section of a pneumatic tire showing one arrangement
of my improvement.
Fig. 3 represents a similar cross section of a pneumatic tire showing another
arrangement my invention.
Fig. 4 represents a similar cross section of a pneumatic tire showing still another
arrangement of my invention.
Fig. 5 represents a similar cross section of a pneumatic tire showing still another
arrangement of my invention.
Fig. 6 represents an enlarged, sectional view of a small portion of a pneumatic
tire with my improvement arranged therein as shown in Figs. 1. and 2.
Like characters of reference refer to like parts wherever they occur on different
parts of the drawing.
The outer casing a, for the air tube is made in any of the usual and well known
manners and may be varied as desired. Within this casing is placed the air tube
which may be made separate from the casing or it may be vulcanized to the casing
in any of the usual manners and as desired.
The object of my present invention as above set forth is to improve the inner
air tube and my improvement consists in the introduction of a layer b, of absorbent
material, preferably fibrous, such as wool, felt, cotton flannel, cotton batten, leather or
other absorbent fibrous material, said layer being introduced within the structure of
the wall of the tube or on the inner surface of the wall of the tube and being
saturated with any suitable sticky sealing preparation which is preferably in a
semi-liquid state and which will be given up readily when required to seal a

page_text: puncture and will remain normally in a permanently sticky and active condition.
This layer b, may be sufficiently large to cover the entire inner surface of the air
tube as shown in Fig. 3 or it may be only large enough to cover only the thread
portion of the tire as shown in Figs. and 4 or any other portion of the inner
tube, as desired.
The structure of the wall, of the inner tube to which my improvements are to
be applied is immaterial, provided it consists of an air tight construction, and it
may consist of a single layer c of rubber or other air tight material, as shown in
Figs. 3 and 4, or an extra layer d may be applied, as shown in Figs. 1, 2, 5 and 6,
and the layer b of absorbent saturated material, which forms the vital part of my
invention, may be applied to the wall of the inner tube either so as
to form a portion of the inner surface of the wall of the tube as shown
in Fig. 4, or the entire inner surface of the tube as shown in Fig. 3,
or it may be applied to the wall of the tube between two layers of its construc-
tion as shown in Figs. 1, 2 and 6. This latter construction is preferable as the
inner layer d forms a covering for the layer of saturated absorbent material b and
prevents the sticky sealing preparation contained therein from sticking the opposite
walls of the inner tube together when they are brought into contact with each
other by the deflating of the tube. In the construction shown in Figs. 1, 2 and G
the layer & may be made of paper, rubber or any other suitable material and is
preferably made very thin, it may be made air tight or not as desired.
If so desired the layer b of absorbent material may be cemented or otherwise
secured to the surface of the layer d the layer being afterwards saturated with
the sealing preparation with the exception of a narrow strip on either edge thereof
which strip is afterwards cemented or otherwise attached to the inner surface of
the wall of the inner tube so as to hold the saturated absorbent layer in contact
with the wall of the tube.
The inner air tube may be made separate from the outer casing as shown in Figs. 1,
2, 3 and 5, so as to be easily removed from or inserted within the outer casing at
will and thereby from what is known in the trade as "double tube tire" or said
inner tube may be vulcanized to and thereby be attached to the outer casing a as
shown in Fig. 4 and from what is known to the trade as a
"hose pipe tire."
66
or
single tube"
The operation with my improved pneumatic tire is substantially as follows:
If a puncturing instrument enters the tire penetrates the inner air tube and enters
the absorbent layer with its contained sealing preparation the puncturing
instrument will be coated with a portion of the sealing preparation which will adhere
thereto and be carried thereby into the puncture when the instrument is withdrawn,
This will stick the walls of the puncture together, and at the same time the pres-
sure of the air within the inner tube will cause the sealing preparation to be
forced together closing the puncture in the absorbent layer forming a bridge
across the puncture in the tube, so as to close the same air tight automatically.
If the quantity of sealing preparation withdrawn from the puncturing instrument
and forced into the puncture by the air pressure within the air tube is sufficient
to automatically close the puncture and it is found that there is a slight leakage
of air it will be readily and quickly closed by deflating the tube and applying
pressure on the outer surface of the tire around said puncture. This will force
the extra quantity of the sealing preparation required from the absorbent layer
into the opening made by the puncturing instrument and close it permanently.
After the puncturing instrument had been withdrawn the action of riding the
tire for a short distance will cause the closing of the puncture in the same manner.
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:
1st. In a pneumatic tire, an inner air tube comprising a layer of absorbent 5
material, saturated with an absorbable preparation, for the purpose set forth.

page_text: 2nd. In a pneumatic tire, an inner air tube having a layer of absorbent material
saturated with a puncture sealing preparation, for the purpose set forth.
3rd. In a pneumatic tire, an inner air tube having a layer of absorbent material
permanently attached to said tube and saturated with a puncture sealing prepara-
tion, for the purpose set forth.
4th. In a pneumatic tire, an inner air tube having a layer of absorbent fibrous
material saturated with a puncture sealing preparation, for the purpose set forth.
5th. A pneumatic tire, having a permanently attached inner air tube, and a layer
of absorbent material saturated with a sealing preparation, for the purpose set
forth.
6th. In combination with a pneumatic tire a layer of absorbent material per-
manently attached to the inner wall thereof, said absorbent layer saturated with
a puncture closing preparation, for the purpose set forth.
Dated the ath dow of NL 1
100
D. YOUNG & Co.
11 & 12 Southampton Buildings, London, W. C.,
Agents for the Applicant.