Improvements in or relating to the Manufacture of Inflatable Air Tubes, and Apparatus therefor.
Year: 1896

page_text: Date of Application, 19th May, 1896
Complete Specification Left, 17th Feb., 1897-Accepted, 20th Mar., 1997
PROVISIONAL DE DOITIATIVA
Improvements in or relating to the Manufacture of Inflatable Air
Tubes, and Apparatus therefor.
A communication from FRED WILLIAM MORGAN, Rubber Manufacturer, and JOHN
ELMER PARKER, Machinist, both of 339 West Lake Street, Chicago, Illinois,
United States of America.
I, ARTHUR HENRY WALKER of 57 Chancery Lane, in the County of Middlesex,
Lawyer, do hereby declare the nature of this invention to be as follows:-
This invention relates to the manufacture of inflatable air tubes for pneumatic tyres
which are composed of an outer tube and an inner tube of rubber or other elastic
material, and a layer of viscous or semi-liquid material interposed between the elastic
tubes.
Prominent objects of the invention are to produce inflatable pneumatic tyre tubes of
this kind in which the inner elastic tube shall fit snugly within the outer elastic tube,
and shall adhere closely to the outer tube at all points along its length by reason of
the intervening layer of viscous material; to prepare such tubes so that no air shall
be left in the viscous layer between the two elastic tubes, and to secure these results
with certainty and in an economical and efficient manner.
In carrying out the invention the outer elastic tube is distended to a diameter
slightly greater than when in its normal condition, and the inner elastic tube, which
has been previously coated with the semi-liquid, viscous material, is then inserted
within the then-distended outer tube. After the insertion of the inner tube, the
distending force applied to the outer tube is removed and the outer tube allowed to
permanently settle about and fit closely upon the inner tube.
The outer tube may be distended preparatory to receiving the inner tube, in a
number of ways, two of which are herein described. In each of these two methods a
tubular sheath or casing, of a size substantially equal to the size the outer tube is
desired to attain when distended, is employed; and the outer elastic tube, after being.
placed in this tubular sheath, is caused to distend until it presses against and conforms
to, the inner surface of the tubular sheath, in one case by filling the tube with
compressed air, and in the other case by exhausting the air from the tubular sheath.
In each of these examples it will be observed that the outer elastic tube is distended
by pneumatic ineans.
The inner elastic tube may be prepared for insertion within the distended outer
tube, by extending or stretching it upon a mandrel of a diameter about equal to or a
trifle larger than the inner tube in a normally inflated condition, and by spreading
upon it a layer of the viscous material, which it is desired shall be interposed between
the two elastic tubes.
The mandrel, which is desirably composed of wood, is preferably as before mentioned
slightly greater in diameter than the inner elastic tube, when the latter is in its normal
or unstretched condition, so that the tube, when extended over the mandrel, will be
slightly stretched and therefore will fit smoothly and closely upon the mandrel.
When the inner tube is in this taut condition, the layer of viscous material is applied
to it by means of a brush or otherwise, care being taken during this application, that
no bubbles of air are allowed to adhere to or form upon the tube.

page_text: In one of the arrangements before mentioned the inner tube, is closed and sealed at
one end, and is drawn upon the mandrel until this closed end abuts closely against the
end of the mandrel.
In this case, the outer elastic tube is turned inside out when placed within the
tubular sheath or casing, and is secured to the sheath at one end by a band or collar,
which clamps to it the marginal portion of the outer tube; the other end of which is
closed. Into the end of the sheath to which the tube is attached and which is slightly
enlarged is fitted the contracted end of a second tubular sheath or casing, which
communicates with a
supply of compressed air, which is controlled by a suitable
admission valve the end of the tubular sheath being closed by an air-tight plug or
stopper, if desired.
When the admission valve is opened, the compressed air, entering the tubular
sheaths and the outer elastic tube inflates and distends this tube, until it conforms to
the inner surface of the sheath, it being understood that to this end the sheath has an
internal bore of a predetermined size so that when the limit of distention is reached,
the outer tube is capable of easily admitting the mandrel having upon it the
inner tube.
At this point the supply of compressed air is cut off, and the mandrel inserted
within the distended outer tube either by hand or power. Obviously, the closed end
of the outer tube will be pushed by the advancing mandrel into said tube, until the
latter has been turned completely inside out, (which will be, of course, back to its
normal position), with the inandrel, the inner elastic tube and layer of viscous
material within it. During this progression of the mandrel, it is found advisable to
slightly open an exhaust valve connected to the tubular sheath or casing so that the
air displaced by the mandrel may gradually escape, and not form an air cushion at the
end of the sheath. When the operation is complete all pressure of air is released
allowing the outer tube to envelop the inner one, after which the whole may be
removed from the mandrel. In this way the outer tube is readily distended, and at
the same time all danger of distention to a bursting degree is avoided; also, the inner
tube is. easily and efficiently inserted within the outer tube in such a manner that the
air is ejected from between the two tubes by a peculiar lapping or curling of the outer
tube over the inner one.
In the second method hereinbefore referred to the inner tube is left open at both
ends, and in this condition is extended upon the mandrel. The outer tube is also open
at both ends, and is secured at these parts to the sheath by bands or collars.
In this case, however, the outer tube is distended by suction or exhaustion, for
which purpose the tubular sheath is provided with a series of apertures, over which a
shell or casing is placed and sealed to the sheath at either side of said apertures and a
pipe leads from this shell to a vacuum or exhaust pump. In this way, when a valve
in the last named pipe is opened, the air is exhausted from the sheath, and the outer
inflatable tube is consequently drawn to the walls of the shell. When in such
position, the mandrel with the inner tube thereon is inserted, after which, air is
admitted between the sheath and the outer tube, thereby allowing the latter to collapse
and envelop the inner tube, with the layer of viscous material between the two tubes.
The bands securing the ends of the outer tube to the sheath may then be released, the
mandrel removed from the sheath, and the complete inflatable air tube removed from
the mandrel.
Dated this 19th day of May 1896
BOULT & WADE,
Agents for the Applicant.

page_text: Improvements in or relating to the Manufacture of Inflatable Air
Tubes, and Apparatus therefor.
A communication from FRED WILLIAM MORGAN, Rubber Manufacturer, and JOHN
ELMER PARKER, Machinist, both of 339 West Lake Street, Chicago, Illinois,
United States of America.
I, ARTHUR HENRY WALKER, of 57 Chancery Lane, in the County of Middlesex,
Lawyer, 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:-
This invention relates to the manufacture of inflatable air tubes for pneumatic tyres
which are composed of an outer tube and an inner tube of rubber or other elastic
material, and a layer of viscous or semi-liquid material interposed between the
elastic tubes.
Prominent objects of the invention are to produce inflatable pneumatic tyre tubes
of this kind in which the inner elastic tube shall fit snugly within the outer elastic
tube, and shall adhere closely to the outer tube at all points along its length by reason
of the intervening layer of viscous material; to prepare such tubes so that no air shall
be left in the viscous layer between the two elastic tubes; and to secure these results
with certainty and in an economical and efficient manner.
In carrying out the invention the outer elastic tube is distended to a diameter
slightly greater than when in its normal condition, and the inner elastic tube, which
has been previously coated with the semi-liquid, viscous material, is then inserted
within the then-listended outer tube. After the insertion of the inner tube, the
distending force applied to the outer tube is removed and the outer tube allowed to
permanently settle about and fit closely upon the inner tube.
The outer tube may be distended preparatory to receiving the inner tube, in a
number of ways, two of which are herein illustrated. In each of these two methods
a tubular sheath or casing of a size substantially equal to the size the outer tube is
desired to attain when distended, is employed; and the outer elastic tube, after being
placed in this tubular sheath, is caused to distend until it presses against and conforms
to, the inner surface of the tubular sheath, in one case by filling the tube with
compressed air, and in another case by exhausting the air from the tubular sheath.
In each of these examples it will be observed that the outer elastic tube is distended
by pneumatic means.
The inner elastic tube may be prepared for insertion within the distended outer
tube, by extending or stretching it upon a mandrel of a diameter about equal to or a
trifle larger than the inner tube in a normally inflated condition, and by spreading
upon it a layer of the viscous material, which it is desired shall be interposed between
the two elastic tubes.
In the accompanying drawings,
Figure 1 is a view showing in elevation the inner elastic tube extended upon a
mandrel.
Figure 2 is a similar view showing the inner tube covered with a layer of viscous
material.
Figure 3 shows in central longitudinal section, the tubular sheath having within
it the outer elastic tube in a deflated or collapsed condition.
Figure 4 is a similar view, showing the outer elastic tube distended and conforming
to the inner walls of the tubular sheath.

page_text: Figure 5 is also a like view illustrating the mandrel having the inner tube upon it,
partially inserted within the distended outer tube.
Figure 6 shows the outer tube completely enveloping the inner tube and
mandrel.
Figures 1 to 6 inclusive relate to the method of distending the outer tube
herein before first meptioned, viz. :-by compressed air.
Figures 7 to 12, inclusive, are views respectively similar to Figures 1 to 6,
illustrating the second method of distending the outer tube, v.-by exhaustion.
Figure 13 is a transverse section of the completed air tube.
The mandrel C, which is desirably composed of wood, is slightly greater in
diameter than the inner elastic tube B when the latter is in its normal or unstretched
condition, so that the tube, when extended over the mandrel, will be slightly stretched
and therefore will fit smoothly and closely upon the mandrel. When the tube B is
in this taut condition, the layer B, Figure 2, of viscous material is applied to it by
means of a brush or otherwise, care being taken during this application that no
bubbles of air are allowed to adhere to or form upon the tube B.
In the arrangement shown in Figures 1 to 6 inclusive, it will be noticed that the
inner tube B, is closed and sealed at the end b, and is drawn upon the mandrel C
until this end abuts closely against the end of the mandrel.
In this case also, the outer elastic tube A is turned inside out when placed within
the tubular sheath or casing D, and is secured to the sheath D at one end by a band
or collar E, which clamps to it the marginal portion a of the tube A; the other
end a' of this tube is closed as shown in Figures 3 to 6. Into the end of the sheath D) to
which the tube A is attached and which is slightly enlarged is fitted the contracted
end of a second tubular sheath or casing F and this tube portion F communicates
through the pipes G and H with a supply of compressed air which may be controlled
by the valve J in the pipe H, the pipe G being connected to the sheath Fat the
closed end, which may be an air-tight plug or stopper, if desired.
When the valve J is opened, the compressed air, entering the tubular sheaths D
and F and the outer elastic tube A inflates and distends this tube until it conforms to
the inner surface of the sheath D, see Figure 4, it being understood that to this end
the sheath D, has an internal bore of a predetermined size, so that when the limit of
distention is reached, the outer tube is capable of easily admitting the mandrel C
having upon it the inner tube B.
At this point the supply of compressed air is cut off and the mandrel C inserted
within the distended outer tube A, as in Figure 5, either by hand or power.
Obviously, the closed end of the tube A will be pushed by the advancing
mandrel Cinto said tube, until the latter has been turned completely inside out
(which will be, of course back to its normal position), with the mandrel C, the inner
elastic tube B and layer of viscous material within it. During this progression of
the mandrel, it is found advisable to slightly open the exhaust valve Jin pipe h, so
that the air displaced by the mandrel may gradually escape, and not form an air
cushion at the end of the sheath. When the operation is complete all pressure of air
is released allowing the outer tube to envelop the inner one, after which the whole
may be removed from the mandrel. In this way the outer tube A is readily distended,
and at the same time all danger of distention to a bursting degree is avoided; also the
inner tube B is easily and efficiently inserted within the outer tube in such a manner
that the air is ejected from between the two tubes by the peculiar lapping or curling
of the outer tube over the inner one.
With reference to the second method shown in Figures 7 to 12 inclusive it will be
seen that the inner tube B is left open at both ends, and in this condition is extended
upon the mandrel C. The outer tube A is also open at both ends, and is secured at
these parts to the sheath D by hands or collars E.
In this case, however, the outer tube A is distended by suction or exhaustion, as
will be readily understood when it is stated that the tubular sheath D is provided with
a series of apertures d, over which the shell or casing D is placed and sealed to
the sheath D at either side of said apertures; and that the pipe K leads from this

page_text: shell D₁ to a vacuum or exhaust pump. In this way, when the valve K' is opened,
the air is exhausted from the sheath D, and the outer inflatable tube A is consequently
drawn to the walls of the shell D, as in Figure 10. When in such position, the
mandrel C with the inner tube B thereon is inserted, as in Figure 11, after which, air
is admitted between the sheath D and the outer tube A, thereby allowing the latter
to collapse and envelop the inner tube B, with the layer B¹ of viscous material between
the two tubes, as in Figure 12. The bands E may then be released, the mandrel C
removed from the sheath D, and the complete inflatable air tube removed from the
mandrel. Such a complete tube is shown in Figure 13, the layer of viscous material
being indicated by the heavy black line B' between the tubes A and B.
Having now particularly described and ascertained the nature of the said
invention, as communicated to me by my foreign correspondents, and in what
manner the same is to be performed, 1 declare that what I claim is :-
1. In the manufacture of inflatable air tubes distending an outer elastic tube to a
diameter somewhat greater than when in its normally inflated condition and inserting
within said outer tube when thus distended an inner tube smoothly extended and in
a condition corresponding substantially to its normally inflated condition and
previously coated with a layer of semi-liquid viscous material substantially as
described.
2. In the manufacture of inflatable air tubes extending the inner tube upon a
mandrel spreading a layer of viscous material upon the inner tube distending the
outer tube to an extent to easily admit the inner tube within the same and inserting
the mandrel having the inner tube upon it into the outer tube when thus distended
substantially as described.
3. In the manufacture of inflatable air tubes extending the inner tube upon a
mandrel spreading a layer of viscous material upon said inner tube when thus extended
distending the outer tube within a sheath having a predetermined bore by pneumatic
means inserting the mandrel having the inner tube upon it into the then-distended
outer tube and releasing the distending force so as to permit the outer tube to collapse
and envelop the inner tube with the layer of viscous material between the two tubes
substantially as described.
4. In the manufacture of inflatable tubes of the class specified extending an inner
elastic tube upon a mandrel spreading a layer of viscous material upon the inner tube
when thus extended turning the outer elastic tube inside out and inserting it into a
tubular sheath and distending it by inflation until it conforms to the shape of the
wall of said sheath inserting the mandrel with the inner tube upon it into the sheath
so that as it advances it will turn the outer tube right side out removing the
inflating pressure from the outer tube during or after the period of advancement
of the mandrel and removing the complete air tube from the mandrel substantially
as described.
5. In the manufacture of inflatable tubes of the kind specified extending an inner
tube upon a mandrel spreading upon said inner tube a layer of viscous material
when thus extended mounting the outer tube within a tubular sheath and distending
it by exhausting the air from said sheath until the tube conforms to the inner walls
thereof inserting the mandrel with the inner tube upon it into the outer distended
tube permitting the air to enter the tubular sheath so that the outer tube may collapse
and envelop the mandrel and inner tube and removing the complete air tube from the
mandrel substantially as described.
6. In apparatus for manufacturing tubes of the kind specified a tubular sheath
adapted to receive an outer elastic tube and to hold the same when distended by
inflation means for inflating the elastic tube and an independent mandrel adapted to
receive an inner tube for insertion within said outer tube substantially as described
and illustrated in the accompanying drawings.
7. In apparatus for manufacturing tubes of the kind specified a tubular sheath.
adapted to receive an outer elastic tube and to give shape to the same when inflated
a second tubular sheath having its end adapted to fit within the end of the first

page_text: tubular sheath and communicating with a supply of compressed air and an independent
mandrel adapted to receive an inner tube for insertion within the outer tube
substantially as described and illustrated in the accompanying drawings.
8. In apparatus for manufacturing air tubes of the class specified a tubular sheath
adapted to receive an outer elastic tube and give shape to the same when distended
and arranged to be exhausted by a vacuum pump means for exhausting the air from
said tubular sheath and an independent mandrel adapted to receive an inner tube for
insertion within said outer tube substantially as described and illustrated in the
accompanying drawings.
TUL 171 1 1
1007
A. H. WALKER.
Boult & Wade,
Agents for the Applicant.