Improvements in Valves for Pneumatic Tyres and other Inflatable Articles.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Valves for Pneumatic Tyres and other Inflatable
Articles.
I, AARON SMITH CARTWRIGHT, of 75, Ford Street, Hockley, in the City of
Birmingham, Manufacturer, do hereby declare the nature of this invention to be
s follows:-
This invention has reference to valves for various inflatable articles, principally
for pneumatic tyres, and relates more particularly to detail improvements in
valves of that class which comprise an elastic chamber located within the interior
or air tube of a tyre and having the walls thereof pierced with one or more.
incisions or slits which are opened by the act of inflation or by the introduction
of a deflating instrument, and are closed normally by the elasticity of the walls
of the said chamber and by the back pressure of air within the tyre. The said
chamber is drawn over the head or flanged end of an axially bored valve stalk
and is clamped between the underside of the head and the walls of the air
chamber by an arrangement of washer whilst located within the bore of the
valve stalk, is the stem of a headed pusher, which is lifted by the application
of a short length of wire or the like from the outside in order to distend the
chamber and open the piercings when it is required to deflate the tyre.
Now I have found in practise that it sometimes occurs, in using such valves,
that the small air slits or piercings in the elastic chamber or cap are liable to
gape or slightly open and so admit of a small leakage of air, this being
occasioned by the internal pressure of the air compressing or flattening the
said chamber down onto the head and causing a distention of the elastic walls
in the neighbourhood of the incisions and in order to remedy this defect, I
propose to mould or otherwise fashion these chambers or caps from india rubber,
preferably with walls of equal thickness throughout and with the material at
both the inside and outside surfaces practically at the same or of about equal
degree of tension. I then turn the said chamber completely inside out, bringing the
inner side or part of least normal surface onto the outside, whereby the material
on the inside of the cap is put into a condition of compression and has a constant
tendency to close and seal the incisions made through the walls of the cap. The
outside walls of the cap are at the same time brought into a state of distension
and assist in the compression of the material at the inner walls.
In carrying out other detail improvements in the construction of valves of this
class and with a view to rendering the same perfectly air tight, I propose to sink
the head or top flange of the valve stem, within which sinking, the head of the
deflation pusher lies and beds itself upon one or more rubber washers loosely
threaded upon the said stem, so that when the valve is in use, the air pressure
flattens down the cap enclosing the valve head and forces the flat end enlarge-
ment of the deflating stem into the sinking and onto the elastic washers, which
thus forms a further seal against the escape of air.
I also propose to form upon the outer end or other convenient part of the dust

page_text: cap of the valve, a stalk or stem of a size adapted to be introduced (when
required) into the bore of the valve stem and to be impinged against the end of
the deflating pusher located therein, thus obviating the necessity of a cyclist
carrying a piece of wire or other loose instrument to use when he requires to
deflate his tyre.
AARON SMITH CARTWRIGHT
By Henry Skerrett,
Agent for Applicant.
Improvements in Valves for Pneumatic Tyres and ther Inflatable
Articles.
I, AARON SMITH CARTWRIGHT, of 75, Ford Street, Hockley, in the City of
Birmingham, 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:—
This invention has reference to valves for various inflatable articles, principally
for pneumatic tyres, and relates more particularly to detail improvements in
valves of that class which comprise an elastic chamber located within the interior
or air tube of a tyre and having the walls thereof pierced with one or more
incisions or slits which are opened by the act of inflation or by the introduction
of a deflating instrument, and are closed normally by the elasticity of the walls
of the said chamber and by the back pressure of air within the tyre. The said
chamber is drawn over the head or flanged end of an axially bored valve stalk
and is clamped between the underside of the head and the walls of the air
chamber by an arrangement of washers whilst located within the bore of the
valve stalk, is the stem of a headed pusher, which is lifted by the application
of a short length of wire or the like from the outside in order to distend the
chamber and open the piercings when it is required to deflate the tyre.
Figure 1 of the accompanying drawing is an elevation of a tyre-valve of this
type embodying my improvements.
Figure 2 is a vertical section of the same.
Figure is a vertical section and a plan of the headed valve body and the
distension pusher.
Figure 4 represents a section and a plan of the distensible elastic chamber
of the valve separate.
Figure 5 is an elevation of the distension pusher separately.
Figure 6 is an elevation of the valve body separately and Figure 7
section thereof.
a vertical
Figure 8 is a view of the dust cap which has a deflation stem upon its end.
Figure 9 represents, upon an enlarged scale, a complete vertical section of the
valve in its normal or closed position, whilst Figure 10 represents a similar
sectional view but showing the elastic cap of the valve distended by the lifting
of the pusher, whereby the piercings in the same are opened to admit of the
escape of air for deflation.
The same letters of reference indicate corresponding parts in the several
figures of the drawing.
Now I have found in practise that it sometimes occurs, in using such valves,
that the small air slits or piercings al, in the elastic chamber or cap «, are liable
to gape or slightly open and so admit of a small leakage of air, this being a

page_text: occasioned by the internal pressure of the air compressing or flattening the said
chamber down onto the head and causing a distension of the elastic walls in the
neighbourhood of the incisions and in order to remedy this defect, I propose to
mould or otherwise fashion these chambers or caps from india rubber with the
material at both the inside and outside surfaces practically at the same or of
about equal degree of tension. I then turn the said chamber completely inside
out, bringing the inner side or part of least normal surface onto the outside,
whereby the material on the inside of the cap is put into a condition of compression
and has a constant tendency to close and seal the incisions made through the walls
of the cap. The outside walls of the cap are at the same time brought into a
state of distension and assist in the compression of the material at the inner walls.
In carrying out other detail improvements in the construction of valves of
this class and with a view to rendering the same perfectly air tight, I propose
to form within the head or top flange of the valve stem b, a sinking or
recess, adapted to contain one or more rubber washers or discs 63 which is
either cemented in position or loosely threaded upon the deflation stem e and
upon the topside of which, the head c', of the said stem lies and beds itself, so
that when the valve is in use, the air pressure within a tyre or the like flattens
or compresses the cap enclosing the valve head and forces the said head or end
enlargement of the deflating stem onto the elastic washer, lying within the sinking,
thus forming a further seal against the escape of air. Instead of a single
washer, may use two or more, lying one upon another.
I also propose to form upon the outer end or other convenient part of the
dust cap d, of the above, a stalk or stem d, of a size adapted to be introduced
(when required) into the hore 6, of the valve stem and to he impinged against
the end, of the deflating pusher located therein, thus obviating the necessity
of a cyclist carrying a piece of wire or other loose instrument to use when he
requires to distend the elastic cap in order to deflate his tyre.
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:-
:
First In valves for inflatable articles of the type herein described, forming
within the head of the body part, a recess or seating within which one or
more elastic washers for the head of the deflating pusher to bed upon are disposed
substantially as and for the purpose as described and set forth.
Secondly In valves for inflatable articles of the type herein described,
providing the dust cap with a stalk or stem adapted to be introduced into the
bore of the valve stem for lifting the deflating pusher, substantially as described
and set forth.
Thirdly: In valves for inflatable articles of the type herein described, making
the elastic perforated cap from moulded rubber which is then turned inside
out, substantially as and for the purpose described and set forth.
Dated this 15th day of Avril 1800
AARON SMITH CARTWRIGHT.
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicant
AARON SMITH CARTWRIGHT.
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicant