Improvements in Valves for Pneumatic Tyres."
Year: 1896

page_text: "Improvements in Valves for Pneumatic Tyres."
I, AARON SMITII CARTWRIGHT of 75 Ford Street, Hockley, in the City of Bir-
mingham, Manufacturer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the valves of pneumatic tyres, and has for its object,
a simple and efficient valve, cheaply produced and not liable to get out of order.
My invention comprises a valve stalk, secured to the tyre or the inner tube and a
distensible and collapsable small sack or chamber secured within the interior of
the tyre, or the inner tube thereof and having a piercing within its walls coming
opposite a solid part of the cover and removed from a hole in the tyre in com-
munication with the valve stalk.
In carrying out my invention of an improved check valve in connection with an
ordinary pneumatic tyre of the Dunlop type, I take a valve stalk with a hole down
The outer stalk is
its middle, wherein an inyer hollow pusher stalk slides.
arranged at its outer end to take any ordinary connection of an air pump, whilst
the inner stalk, or both the inner and outer stalks, is or are in communication with
a small elastic or other-chamber situated within the interior of the tyre air tube,
and cut off therefrom other than a small hole formed in the bottom wall of the
same, out of line with the hole in the valve stalk or stem, so that when this
chamber is collapsed, this small hole, which is preferably surrounded by a slight
thickening in the rubber, presses against the inner walls of the air tube, and when
internal pressure is exerted upon it after inflation has been performed, the air in
the tyre is prevented from escaping through the hole, which is closed by the bottom
of the chamber being pressed against the walls of the tyre.
When the tyre is desired to be deflated then the pusher inner stalk is pressed
inwards and by forcing or distending the valve chamber, the bottom of the said
collapsable chamber is pushed clear of the inner tube of the tyre and the hole in
the same made open for the egress of air.
The self-closing or collapsable chamber may be made in the form of a distensable
sack or a small bag with gussetted sides, and the bottom of the same may be
strengthened at the part where the pusher comes for opening out the same, by plys
of canvas or the like. Or the gussetted chamber may be arranged to be self closing
by a suitable spring.
As a further part of my improvements, a part of the walls of the inner tube,
within the collapsable chamber, and opposite the hole in the bottom of the same,
may be formed or provided with a tooth or pointed stud, over which the-hole passes;
whereby an air seal is formed by the pressure of the confined air forcing the bottom
of the collapsed chamber against the inside of the inner. tube and the hole therein
up the sides of the stalk.
As a further form of my improvements, the valve consists of an elustic chamber
made distensable by a pusher, and having within its walls, a puncture or slit,
which, when the walls are distended gapes or opens out so as to admit of the egress
or ingress of air from or into the tyre, but after shrinking back to its normal
dimensions with the pressure of the air in the tyre at the back of it, the puncture,

page_text: hole or incision is closed. This elastic chamber is attached to the tyre by a flanged
inner end of a tube passing through its mouth and stretching or expanding the
walls of the chamber near the mouth entrance, so as to make the said flanged end
act as an internal abutment or collar, between which, and the opposed parts of the
tyre walls or rim, the said contracted mouth end of the chamber or sack is gripped.
The clamping up is performed by a nut on the outside screwed tubular sleeve or body
of the valve, whilst the extension of the valve chamber is effected by the internal
application of the head or disc end of a stalk passing and sliding axially up the
middle of the valve body.
To make the connection, expand the mouth of the chamber over the flanged end
and then pass the same through a hole (of less normal size than the collar or flange)
into the interior of the tyre. Then slip on a washer up to the tyre surrounding the
hole and next pass the neck of the tyre through the hole in the rim, where it is
secured by a screwed-on lock uut. The screwing of the flexible pump connection
onto the end of the valve, forces the protruding end of the pusher stalk inwards,
distends the chamber and opens the puncture or slit, therein, whilst on the
removal of the said connection the plunger is forced outwards by the collapse of the
chamber and the slit or puncture is closed.
into
Instead of having a slit or puncture in the valve chamber, the air may pass
or out of the same through a small pipe of thin material which is closed against the
outside of the valve chamber by the internal pressure of the air, and opened, for
deflating by the pusher or a tube pusher.
The pipe is made of extremely thin rubber and is preferably normally flat, so
that its inside walls come together and form a check joint for preventing the exit
of air when internal air pressure in the tyre is exerted upon it. It is understood
that this pipe, which may be of any desired section, extends into the inside of the
tyre.
As a further form of my improvements, I construct a valve by taking an out-
side screwed stalk or body having a flanged inner end over which the mouth or
entrances of two elastic chambers are stretched and firmly held against the inside
of a tyre, whereby a sound joint is made. The inner elastic chamber, which is
somewhat of the figure of a mush-room head, as a hole through its middle where-
through a headed pusher rod passes with the head coming against the inside of the
outer and mushroom-headed or other shaped chamber, which has a small thorough-
fare hole or perforation through its side.
Normally the inner and outer chambers are collapsed by the air pressure exerted
upon the outside walls of the outer chamber thereby seating the perforation against
an vupierced part of the outer walls of the inner chamber, and forming a sound
joint for preventing the escape of air.
To inflate the tyre, screw on the flexible connection in the ordinary way, when
the pusher rod is forced inwards and the outer chamber thereby distended by
stretching, thus taking the piercing away from the walls of the inner chamber so as
to leave a clear passage therethrough. The air travels through the pusher stem
or through a hole in the inner chamber and thence through the space between the
two chambers and outwardly through the hole in the outer chamber and into the
tyre.
Instantly the pressure of the pusher piece is relieved the walls of the one chamber
are pressed up to the walls of the other chamber, so preventing the return of air,
partly by the air pressure inside the tyre and partly by the contraction of the walls
of the chambers themselves.
Instead of employing two separate chambers, I may employ a single long
chamber or elliptical sack, one end of which is turned cupwise into the other end.
Dated this 24th day of December 1890.
AARON SMITH CARTWRIGHT.
By Henry Skerrett,
Agent for Applicant.

page_text: The return stroke of the inflator relieves the external pressure and the internal
pressure of air in the tyre now expends itself upon the outside walls of the outer
chamber or diaphragm, and presses both it and the head of the pusher forcibly
down upon their seating, thus forming a trap or check against the outward escape
of air. This operation is repeated until the tyre is fully inflated.
In order to deflate the tyre, it is only necessary to press upwards the valve stalk,
when the outer sack or flexible overlay chamber is distended as seen in figure 5,
and the air can freely escape through the piercings or holes,, which have been lifted
from contact with the seating.
Figure 7 represents the stem, head, flexible diaphragın and the bed or seating
of a modified form of valve.
a is thic valve, a' its head; a³ the screwed stem and a the axial hole up its middle.
a is a turned over edge of the said head for keeping or securing the combined
diaphragm d and bed c, in position.
The operation of this modification is exactly the same as the first described and
preferred form of my invention.
It is obvious that instead of both diaphragm and its bed or seating being made
of one piece, it may be made of two discs of india-rubber, the upper one being
pierced and the other coming underneath and forming, the bed.
It must be also understood that it is not absolutely essential to employ the rubber
seating or bed on the head of the valve, as the outside chamber or diaphragm alone
when bedded upon the naked metal of the head by the inner pressure of the com-
pressed air in the tyre (as represented in figure 8) would be sufficient to form a
sound check against the escape of air.
b is
In figure 8, a is the head of the valve a, a is the axial bore of the same.
the pusher and 6 the pusher head, whilst d is the outer chamber or diaphragm,
pierced' with air holes d', and bedding itself directly upon the outer face a³,
said stem head a¹.
of the
Figure 9 represents a further modification of my invention, in which the dis-
tensible chamber or sack is made from out of, or is located within, the inner air
tube, or from out of the walls of a separate sack or chamber located within the
interior of a tyre.
a is the valve body, d is the distensible chamber, d¹ are the air passages, bedding
or coming upon an unpierced part of the bed c, located underneath the top of the
head a', which bed may either be naked or be faced with thin india-rubber. bis
the pusher located in the axial hole a², in the body; b is the pusher stem and ba
the head thereof, for lifting the pierced part of the chamber off its bed. Flats b³,
are made upon the sides of the stem to admit of the air passing under the head and
into the chamber d., e is the tyre, f the wheel rim and g the nut for securing the
valve to the rim.
Figure 10 represents a vertical section of a still further form of my improve-
ments, and figure 11 is an elevation of the deflating pusher tube.
Figure 12 is a like section as figure 10, but showing the deflating pusher in
position for deflating the tyre.
a is the body part of the valve, having an axial holé-a, up its middle, terminat-
ing in the lead a', enveloped by a distensible chamber or sack d, having a small
tube or pipe d', which is normally collapsed by the pressure of the air inside the
tyre, but is opened out when inflation is in progress, by the external pressure of
pumped-in air, whilst to deflate the tyre, the deflating tube b, is passed up the axis
of the valve stem and then up the throat of the pipe d, and on the open end of the
said tube b, extending into the inside of the tyre (as shown in figure 12), air rushes
out or escapes through the same.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
ciaim is :-
First A valve for pneumatic tyres comprising a distensible chamber or

page_text: diaphragm pierced or provided with small air hole or passage, and adapted to be
lifted off its seating on a solid part or bed of the valve by external air pressure
applied in the act of inflating.
Secondly: A valve for pneumatic tyres, comprising a distensible chamber or
diaphragm, pierced or provided with a small air hole or passage and enclosing or
enveloping the head or bed of a valve body, and adapted to be lifted off its seating
on the said bed by external air-pressure applied in the act of inflating a tyre, sub-
stantially as herein described.
Thirdly: A valve for pneumatic tyres, comprising a distensible chamber or
diaphragm, pierced with a small hole or air passage and enclosing the head or end
of a valve body faced or provided with a rubber or elastic seating or bed, said
diaphragm being lifted off its bed, so as to admit of the passage of air through its
piercing, by external air pressure when a tyre is being inflated, substantially as set.
forth.
Fourthly: In a tyre valve, the combination with a valve body whose head end
may either be naked or faced with an elastic seating or bed, and is enclosed within
a distensible chamber or diaphragm pierced with small air passages, of a pusher
whose head end is enclosed within and comes against the inside of, the said
diaphragm whilst the stem or shank of the same lies within, and may extend
beyond the open end of the bore of the said valve body, substantially as described
and set forth.
Fifthly: A tyre valve, provided with a distensible chamber or diaphragm,
having an air passage in the form of a small collapsable and distensible pipe or
tube, normally closed by the inside air pressure, and capable of being opened for
inflating by external air pressure, and for deflating by a small inserted tube, sub-
stantially as described and set forth.
Sixthly: The improvements in tyres, valves, and in the construction, arrange-
ment and combination of the parts of the several forms of valves, substantially as
herein described and set forth.
AARON SMITH CARTWRIGHT.
By Henry Skerrett,
24 Temple Row, Birmingham. Agent for Applicant.