Improvements in Apparatus for Inflating Pneumatic Tyres.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Inflating Pneumatic Tyres.
I, FREDERICK LEONARD BALL, of 285, Wandsworth Bridge Road, Fulham,
London, S.W., Chemical Manufacturer, do hereby the nature of this invention
to be as follows:-
My invention relates to improvements in connection with the apparatus for
inflating pneumatic tyres by means of compressed or liquefied carbonic acid gas
stored in cylinders fitted with valves to allow the gas to escape when desired &
also with pressure reducing valves or safety devices to prevent bursting of tyres.
With apparatus of the kind described it is not possible (except by weighing) to
ascertain the amount of gas at any time in the cylinder & in order to obviate this
I provide a guage to indicate the pressure. Of course so long as any gas in the
liquid form remains in the cylinder the pressure is constant but so soon as the
pressure commences to diminish it is known that there is but a certain quantity
of gas remaining in the cylinder. I may utilize this diminution to indicate in
any convenient way such as by arranging a piston in the cylinder working against
a spring or definite power the rod of which shall say slightly project through the
end of the cylinder. So soon as the liquid gas has all expanded the strength of
the spring will overcome the resistance of the gas & the end of the rod will pass
out of sight thus giving notice that the cylinder will soon need recharging. It
is obvious that this principle can be carried out in different methods.
In order to prevent inconvenience owing to the cylinder being found to be
empty when required to be used I may combine with it an ordinary inflator or
so construct it that on emergency it may be used as an inflator.
To carry this out I may outside the cylinder fit another tube in which the
cylinder is capable of sliding & on the end of the cylinder fit a leather piston or
other suitable device. Valves may be inserted in the closed end of the tube to
allow ingress & not egress of air except through the flexible tube connected to the
said metal tube. I may use the flexible tube used with the cylinder & adopt
suitable means to retain the tube in position. The tube is made of suitable
material.
Or the inflator may be fitted with a piston capable of sliding inside & fitted
with suitable valves that when empty of carbonic acid gas it can be used to
pump air.
I may in some cases dispense with a pressure reducing valve being fitted to the
cylinder of gas & fit the cylinder with an ordinary valve & attach thereto an
indicator or guage to show the pressure in the tyre & provide a safety valve or

page_text: I may
other device to prevent the accumulation of an excess pressure in the tyre.
in some cases use the cylinder with valve & safety device & omit the use of
indicator or guage.
A convenient form of device to prevent the accumulation of too great pressure
will be to attach a metal or other tube to the valve said tube having a small hole
bored therein. Over this tube & covering the hole I fit a sleeve of indiarubber
or suitable material of such length & strength as will prevent the gas from
escaping until the pressure exceeds the desired limit. The amount of the pressure
which it is desirable not to exceed in the tyre may be varied by sliding the rubber
sleeve on the tube so as to vary the distance between the hole in the tube & the
edge of the sleeve.
I may also provide on the cylinder a safety valve of any convenient form to
prevent the possibility of the cylinder bursting. This may be combined with
the piston to indicate the pressure or may take the form of a convenient material
that will rupture at or about a given pressure.
I provide nonconducting material for the protection of the hands from the cold
produced by the expansion of the gas or the cover previously mentioned may be
made to serve the purpose.
Means may also be provided for releasing the gas in the flexible tube after the
valve on the cylinder is closed.
In order to fill the cylinders with a definite quantity of gas I employ a cylinder
that is filled with liquefied gas, This cylinder is fitted with a piston capable of
traversing the cylinder & one end of the cylinder is connected to the cylinder to
be filled. When the piston is traversed in the cylinder the contents of the same
are forced into the cylinder to be filled. The piston is worked in any convenient
manner & the cylinder can be fitted with necessary valves & to work automatically
for rapid filling, & apparatus provided to open & close the valves on the cylinder
to be filled.
Or I may provide small cylinders or capsules of gas sufficient for the inflating
of one or more tyres & arrange a suitable apparatus to affix to the valve of the tyre
to open the small cylinders or capsules of gas & allow the same to escape into the
tyre in all cases providing devices to prevent accumulation of too great pressure
in the tyre or the quantity of gas in the capsules or cylinders may be limited
with this latter object. Or the cylinders or capsules may be so constructed that
the attaching of the same to the valve shall allow the escape of the gas into the
tyre.
It is obvious that suitable gases other than CO₂ may be used.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Inflating Pneumatic Tyres.
I, FREDERICK LEONARD BALL, of 285, Wandsworth Bridge Road, Fulham,
London, S. W., Chemical 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 relates to apparatus of the kind in which the inflation of the tyre
instead of being effected by a pumping action with an ordinary inflator is effected
by compressed or liquefied gas contained in a suitable receiver.

page_text: With apparatus of this kind it has been found that inconvenience is likely to
arise by reason of the charges of compressed or liquefied gas becoming exhausted
at a time when it is not possible to replenish the gas container, with the result
that the user is inconvenienced and compelled to continue the journey without a
proper inflation of the tyres.
One of the chief objects of my invention is to overcome this inconvenience by
so constructing the gas container that it will also serve as an ordinary inflator
for charging the tyres with compressed air in the usual manner.
Other important features of my invention have reference to providing simple
means on the gas container for indicating when the contents thereof are becoming
exhausted; to the construction of the various valves employed in the apparatus;
to means whereby the parts of the apparatus coming into direct contact with the
liquefied gas will not be liable, by reason of the intense coldness of the gas, to
injure the user's hands; and to various other details hereinafter set forth.
The gas with which I charge the container is preferably carbonic acid in a
liquefied condition.
In order that my invention may be fully understood and readily carried into
effect I will proceed to describe the same more fully with reference to the
accompanying drawings in which :-
Figure 1 is an elevation of my combined gas container and pump and
Figure 2 is a longitudinal section of the same.
Figure 3 is a longitudinal section of the flexible pipe for connecting the
apparatus to the valve of the tyre such pipe being provided with a safety valve
for avoiding overcharging of the tyre.
Figure 4 is a longitudinal section shewing a modified construction of the
apparatus.
Figure 5 is a detail view shewing the means employed for indicating when the
gas container is becoming exhausted.
Figure 6 is a detail view shewing the construction of a safety valve for the
gas container.
Figure 7 is a detail sectional view of a portion of the piston rod employed in
the apparatus illustrated by Figure 4.
a
Referring more particularly to Figures 1, 2 and 3, A is the gas container,
which is constructed in the form of a hollow cylinder provided at one end with
a neck A¹ having a screw-threaded hole for the reception of a valve rod B. This
rod passes through a gland A³ with which the mouth of the said neck is furnished
to prevent escape of the gas at this part. The inner end of the screw threaded
hole in the neck A terminates in a shoulder
against which a
valve a¹ can be tightly pressed by revolving the said valve rod B,
thereby closing the aperture a² communicating with the interior of the gas
container A. The said valve rod B is formed with a longitudinal central
passage a³ which is closed at its inner end and communicates with a lateral
passage a through which, when the valve a¹ is open, the gas from the container A,
can enter the longitudinal passage a³ and thereby reach the inflation valve of the
tyre through a suitable flexible tube. In order to facilitate the adjustment of the
valve rod B it is provided with a boss or milled head B₁ by which the user can
readily turn it in a direction to cause the valve a¹ to be firmly held against its
seat, or in the opposite direction to release said valve. When the valve rod is
rotated in a direction to lift the valve from its seat the gas will escape past said
valve and reach the lateral passage a leading to the central passage a³ before
mentioned.
Around the gas container A is a metal casing C which is of such a diameter
internally that the gas container A will readily enter and be capable of freely
reciprocating therein like a plunger or ram. To the inner end of the gas container
is connected a piston I consisting of a cup leather which is held in place by a
nut d screwing on to a screw threaded stem d'. The outer casing C is closed at
one end with the exception of the small passage c which extends through a nipple c¹

page_text: with which such end is furnished. Within the nipple is arranged a sphere that
acts as a non-return valve as is well understood.
E is a short length of flexible tube having at each of its ends screw threaded
nipples E¹ whereby the outer end of the valve rod B, or the nipple c¹ of the pump,
can be coupled to the inflation valve of the tyre in the ordinary manner.
By this construction it will be observed that if the compressed or liquefied gas
in the container A should be consumed at a time when it is not possible to replenish
said container, the user can by reciprocating the said container within its surround-
ing casing C utilize the apparatus for inflating the tyres with air in an analogous
manner to that of an ordinary tyre-pump. For the purpose of keeping the gas
container in place within the outer casing when the apparatus is not being used
as a pump, I provide a pin a5 on the gas container, which pin works in a suitable
slot in the casing, like the pin of a bayonet joint.
One of the aforesaid screw threaded nipples E of the flexible tube E is pro-
vided with a lateral opening e which is normally kept closed by a flexible sleeve el
composed of indiarubber or other suitable material. This flexible sleeve serves
as a safety valve for preventing the overcharging of the tyre, that is to say, when
the pressure within the tyre reaches a predetermined degree, the resistance of the
said flexible sleeve will be overcome and the gas will escape through the lateral
opening e by reason of the said sleeve's uncovering it, and the pressure will thereby
be relieved. Thus not only will the bursting of the tyre be avoided but the
escaping gas will indicate to the user that the tyre has been sufficiently inflated.
Referring now to Figure 4 which illustrates a modified construction of the
apparatus shewn in Figures 1 to 3, the gas container A is provided with an
internal piston D, which is similar in construction to that already referred to in
Figure 2. The said piston is connected to a piston rod which is formed in two
portions D1, D2 connected together by a screw joint.
The portion D¹ of the piston rod is prevented from turning by forming on the
collar a projection that works in a shallow groove formed in the wall of the
gas container A.
The portion 12 of the piston rod extends through the neck A¹ of the gas con-
tainer and is capable of being revolved by the finger piece B' like the valve rod B
in Figures 1 and 2. The inner end of this portion D2 is provided with a screw
threaded stem D³ and a shoulder 1, the said stem screwing into a correspondingly
threaded cavity in the end of the portion D₁ of the piston rod.
A leather or other suitable washer D5 is interposed between the shoulder I'
and the contiguous end of the portion D¹ of the piston rod such washer being
secured to the said portion D¹ by cement or otherwise. The portion 12 of the
piston rod is formed with a longitudinal passage D the inner end of which
terminates in the shoulder D so that when the portion D2 of the piston rod is
firmly screwed into the portion D₁ this passage D is tightly closed by the
washer D which then acts as a valve to prevent the gas within the container
from flowing through the passage De. When however it is desired to inflate the
tyre with the gas the aforesaid portion D2 of the piston rod is turned in a direction
to unscrew it from the portion D' whereby the inner end of the passage Do is
uncovered as shown in Figure 7 and the gas in the container A is permitted to
flow along the passage 16 and thence through the flexible tube E to the tyre in
the manner already explained.
The opposite end A³ of the gas container A is provided with passages ab
which are normally kept closed by spring controlled valves a' the stems of which
are carried by the plate or partition as located within the gas container A. The
aforesaid plate or partition is formed with a series of perforations a through
which when the apparatus is used as a tyre inflating pump by reciprocating the
piston D, the air that is drawn into the container A through the valve controlled
passages a can be forced through the nozzle c¹ and the flexible pipe E to the tyre.
In order to avoid leakage of the compressed gas past the piston 1) and its con-
sequent escape through the aforesaid openings a³ I provide the aforesaid plate or

page_text: partition as with an annular rim or flange a¹0 around which the cup leather
of the piston D fits when the latter is in the position represented in Figure 4.
The pressure of the gas within the receptacle A forces the cup leather firmly
against the said rim or flange and thereby makes a tight joint at this part, past
which the gas in the receptacle A is unable to escape.
For the purpose of facilitating the charging of the gas container with the com-
pressed or liquefied gas I provide it with a spring controlled valve F which under
the internal pressure within the container A keeps the charging opening f closed.
When however the gas within the container A has been expended the said valve
will readily open by the pressure of the incoming gas which is admitted to the
receiver through a tube connected to the portion of the valve by a suitable
union or other connection. f is a detachable cap which is adapted to be screwed
on to the portion f of the valve after the gas container has been charged.
To indicate to the user of the apparatus when the gas container is becoming
exhausted I take advantage of the fact that the pressure within the container
remains approximately constant so long as the gas retains its liquefied condition,
such pressure only diminishing when the charge has been nearly all used up and
is assuming its gaseous condition. I provide a plunger G which projects through
a stuffing box g that is screwed into the wall of the gas container. The inner
end of.this plunger is furnished with a dise or piston g¹ between which and the
stuffing box g there is interposed a spiral spring g². The outer extremity of the
plunger has a shoulder or collar g³, and the gland g of the stuffing box is formed
with a corresponding cavity or recess into which this collar is adapted to enter
when plunger occupies its inward position. So long as the pressure within
the container A remains at the normal the aforesaid plunger is kept in the
position shown in Figure 5 with its outer end visible to the user and the spring g
under compression. When however the pressure falls, owing to exhaustion of
the contents of the container and their consequent change from the liquid to the
gaseous condition the compressed spring g³ will re-act and cause the plunger to
move inwardly until its collar g³ lies within the before mentioned cavity g
When this takes place the user will know that the charge within the receiver A
is on the point of being exhausted.
In Figure 6 I have represented a simple form of safety valve with which the
gas container may be provided in order to insure that excessive pressure which
might arise within the container shall be relieved and any serious consequences
that might result from the bursting of the container be thereby avoided. This
valve consists of the disc of copper or other appropriate material H the circum-
ferential edge of which rests upon a shoulder h formed around the opening h¹
in the wall of the gas container, the said disc being held in this position by means
of an annular cover or nut h² screwing down upon it. This nut may be formed
with holes h³ for permitting of its being readily screwed to or unscrewed from the
container.
The said apparatus is coated or encased in celluloid or other suitable heat
non-conducting material for the purpose of preventing the user from experiencing
any inconvenience which might arise by the naked hands touching the portions of
the apparatus that become extremely cold by contact with the liquefied gas.
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. Tyre inflating apparatus capable of being used either as a container for
liquefied or compressed gas, or as an ordinary tyre inflator, for the purpose
specified.
2. The combination with the aforesaid apparatus of a safety valve which is
adapted to prevent overcharging of the tyre substantially as described with
reference to Figure 3 of the accompanying drawings.
3. The combination with the aforesaid apparatus of an indicator substantially

page_text: as described with reference to Figure 5 for enabling the user to readily, observe
when the charge in the container is becoming exhausted.
4. The combination with the aforesaid apparatus of a safety valve constructed
substantially as described with reference to Figure 6 for the purpose specified.
5. Inflating apparatus having its parts constructed and arranged to operate
substantially as hereinbefore described with reference to Figures 1 and 2 or
Figure 4 of the accompanying drawings for the purposes specified.
Dated this 25th day of Avost 1808
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.