Title of Invention	APPARATUS FOR REGULATING AIR FLOW IN A PNEUMATIC TYRE OF A VEHICLE.
Abstract	An apparatus for regulating airflow into a rim mounted vehicle tyre is disclosed. The apparatus has an elongated valve housing (1) with an inlet end (1A), an outlet end (2) and a central portion between the outlet end (2) and inlet end (1 A). The outlet end includes a rim insertion portion (3) configured to fit into an aperture in the tyre rim. A piston (8) is disposed within the housing (1). The piston includes a valve member (19). A coil spring (22) acts between the housing (1) and piston (8). In use, the piston (8) is biased to an open position for passage of air into the tyre and is movable against the spring bias under air pressure build up in the tyre to a closed position. At the closed position, the valve member (19) seals against a valve seat (21). The piston (8) and spring (22) are located in the central portion of the housing (1) clear of the rim insertion portion (3). The rim insertion portion (3) is of a reduced size not obstructive to the mounting of the tyre.

Title of Invention

APPARATUS FOR REGULATING AIR FLOW IN A PNEUMATIC TYRE OF A VEHICLE.

Abstract

An apparatus for regulating airflow into a rim mounted vehicle tyre is disclosed. The apparatus has an elongated valve housing (1) with an inlet end (1A), an outlet end (2) and a central portion between the outlet end (2) and inlet end (1 A). The outlet end includes a rim insertion portion (3) configured to fit into an aperture in the tyre rim. A piston (8) is disposed within the housing (1). The piston includes a valve member (19). A coil spring (22) acts between the housing (1) and piston (8). In use, the piston (8) is biased to an open position for passage of air into the tyre and is movable against the spring bias under air pressure build up in the tyre to a closed position. At the closed position, the valve member (19) seals against a valve seat (21). The piston (8) and spring (22) are located in the central portion of the housing (1) clear of the rim insertion portion (3). The rim insertion portion (3) is of a reduced size not obstructive to the mounting of the tyre.

Full Text	WO 2004/030952 PCT/AU2003/001283 AIR FLOW CONTROL APPARATUS FIELD OF THE INVENTION This invention relates to fluid control devices. More particularly although not exclusively it discloses an improved pressure cutoff valve for vehicle tyres. BACKGROUND TO THE INVENTION Correct pressure in vehicle tyres is of considerable importance. Excessive pressure can cause premature tread wear and loss of traction in the wet. Low pressure on the other hand can cause loss of stability when cornering and tyre failure from excessive wall flexing. While most service stations provide facilities for drivers to check their tyres the gauges are often defective or at best inaccurate. In order to alleviate such problems valves have been proposed for tyres which during filling automatically cut off the air supply once a preset pressure is reached. The user therefore does not need to be concerned about monitoring tyre pressure during filling. Rather it is only necessary to maintain the air hose fitting on the tyre valve until it automatically cuts off. These valves typically use a piston which is biased to an open position by a compression spring during filling but is moved against said bias to a closed position when an applied force from the internal tyre pressure reaches a preset amount of say 200 kpa. Existing valves have the disadvantage however that the compression spring and piston are located in the base of the valve assembly which is therefore enlarged and WO 2004/030952 PCT/AU2003/001283 -2- protrudes a substantial distance through into the interior of the tyre rim. This obstructs the fitting of the tyre and can result in the base of the valve housing being damaged during initial inflation as the tyre bead expands onto the rim. SUMMARY OF THE INVENTION It is therefore an object of this invention to ameliorate the aforementioned disadvantage and accordingly a apparatus for regulating air flow into a rim mounted pneumatic vehicle tyre is disclosed, said apparatus having an elongated valve housing with an inlet end, an outlet end and a central portion, the outlet end including a rim insertion portion configured to fit into an aperture in the tyre rim, a piston disposed within said housing and including a valve member, a coil spring acting between said housing and piston whereby in use of said apparatus the piston is biased to an open position for passage of air into said tyre and is movable against said bias under force of air pressure build-up in said tyre to a closed position at which the valve member seals against a valve seat to close off said passage of air wherein the piston and spring are located within said central portion of the housing clear of the rim insertion portion so that said rim insertion portion is of a reduced size not to obstruct the mounting of said tyre. Preferably said piston is fitted with a visual indicator to WO 2004/030952 PCT/AU2003/001283 -3- show position. It is further preferred that said spring acts in compression between a flange on the piston and an interior shoulder of the valve housing. It is further preferred that the visual indicator is a band which is visible through a transparent portion of a cap fitted to the housing. It is further preferred that the cap is adapted to be turned down onto a threaded seat to an over-ride position whereby said band and piston are held to said open position irrespective of tyre pressure It is further preferred that the valve housing be fitted with a schrader type one way valve at the inlet end. BRIEF DESCRIPTION OF THE DRAWINGS Two currently preferred embodiments of this invention will now be described with reference to the attached drawings in which:- figure 1 is a perspective side view of an automobile tyre valve according to the invention, figure 2 is a vertical cross-sectional of the valve of figure 1 when in the open position, and WO 2004/030952 PCT/AU2003/001283 -4- figure 3 is a cross-sectional view along the lines A-A of figure 1, figure 4 is a cross-sectional view similar to figure 2 but with the valve in the closed position, and figure 5 is a cross-sectional view of a spring tension adjustment plug which can be fitted to the valve of figure 1, and figure 6 is a vertical cross-sectional view of a second embodiment of an automobile tyre valve according to this invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to figures 1 and 2 the valve housing 1 may comprise an elongated cylindrical casing with an inlet 1A at the top as shown and an outlet 2 at the bottom. The outlet end of the housing preferably comprises an insertion sleeve 3 with a groove 4 and shoulder 5 which adapt said sleeve for fitting through an aperture 4A in a pneumatic tyre rim 5A. Preferably the outlet end is moulded from rubber or other suitable material to obtain the necessary pressure tight seal to the rim. At the inlet end 1A there is a short pipe section 6 of reduced diameter to connect with an air supply hose nozzle such as that provided at service stations. Immediately below this is a transparent cap 7 through which the position of an internal indicator band (which may be coloured red) can be viewed as described later. WO 2004/030952 PCT/AU2003/001283 -5- Referring more specifically to figures 2 and 3 there is a piston 8 which is longitudinally slidable between the housing cylinder wall 9 and a central tube 10. The tube 10 is part of a sub-assembly which includes the pipe 6 with a schrader type inlet valve 11 of known construction. This sub-assembly is threaded into or otherwise rigidly connected to the housing at 12. The transparent cap 7 also fits onto the housing at this location and provides a view window between the top of said housing 12A and the pipe 6. As the pipe 6 and housing are fixed relative to one another this cap 7 takes no load and can therefore be of nonstructural material such as a low cost plastic. There are 0-rings 13, 14 fitted to provide a sliding pressure tight fit between both the outside of piston 8 and cylinder 9 as well as the internal piston bore 15 and tube 10. Preferably a directional low friction cup seal 16 may also be fitted into a nich 17 in the piston immediately below 0- ring 13 to further ensure against air leakage between the piston and cylinder. The piston 8 at its upper end mounts the indicator band 18 and towards the lower end the bore 15 is fitted with a valve member having a bevelled head 19 and upwardly directed needle 20. The needle extends up through a seat 21 formed at the base of tube 10. The seat is shaped to form a pressure tight seal when engaged by the bevelled head 19 of the valve member. There is also a tension spring 22 which acts between a transverse pin 23 located across the housing just above the insertion sleeve and the centre WO 2004/030952 PCT/AU2003/001283 -6- 24 of the piston. Preferably the spring at one end hooks over pin 23 and at the other end seats in spiral grooves around the centre of the piston. In figure 2 the piston is held to its lowermost position where the band 18 abuts the top of the housing. In accordance with this invention it will be noted that the tension spring 22 and piston 8 move within the centre portion of the housing above the insertion sleeve 3. This allows the rim insertion sleeve at the outlet end to be greatly reduced in diameter and length. It therefore provides virtually no obstruction to the tyre bead during initial mounting and inflation of said tyre on the rim. The moulded rubber construction of the insertion sleeve with the current embodiment also allows the housing 1 to flex relative to the tyre rim to reduce the chances of breakage. In the open position of figure 2 a supply of pressurised air is able to flow through the inlet schrader valve 11, down through tube 10, around open valve member 19, through ports 26, along clearance space 27 between the spring 22 and housing to enter the tyre (not shown) through outlet 2. As the pressure inside the tyre builds up however a force (arrow B) acts against the underside of the piston moving it upward. At a preset cutoff pressure of say between 80 and 1000 kpa determined by the underside area of the piston 8, the deflection constant of the spring 22 and the position of valve seat 21 the upward displacement of the WO 2004/030952 PCT/AU2003/001283 -7- piston 8 causes the valve head 19 to close into said seat as shown in figure 4. This cuts off further air flow into the tyre. It will also be noted from figure 4 that the band 18 simultaneously moves upward within transparent cap 7 to indicate that the preset pressure has been reached in the tyre and the cutoff valve 19 is closed. If tyre pressure subsequently falls below this preset pressure the piston and indicator band 18 move downwardly under the tension force of spring 22 to show low pressure and the valve 19 opens in preparation for filling. Leakage of air out of the tyre however is prevented by the one way operation of the schrader valve 11 which only allows discharge through deliberate depression of insert stem 28. As an alternative to the fixed transverse pin 23 for holding the lower end of the spring 22 a threaded anchor plug 29 as shown in cross-section by figure 5 may be turned into the housing at the same location. This plug has an upstanding pin 30 with a circumferential groove 31. The lower end of the spring is then shaped to seat in this groove so that rotation of the plug using an alien key or the like on socket 32 adjusts the spring tension and thus the cutoff pressure of the valve. A series of apertures 33 around the periphery of the plug allows air to pass through to the outlet 2. With the second embodiment of the invention shown in figure WO 2004/030952 PCT/AU2003/001283 8 6 the main items that correspond in function to those of figures 1, 2 and 4 are indentified by the same numbers/letters which are however primed (') to distinguish them. In this case the spring 22' is still located well clear of the rim insert portion 3' but now acts in compression between a circular flange 35 near the bottom of the piston 8' and an interior shoulder 36 of the valve housing 1'. A cup seal 36A is also fitted in place of the inner o-ring 14 of the first embodiment. With the valve in the open position shown the piston 8' is held down by the spring 22' so that air can flow through the inlet schrader valve 11', down through the tube 10', past the open valve seat 21' and through ports 37 to enter the tyre via outlet 2'. As pressure within the tyre builds up a force (arrows B') acts against the underside of the piston 8' to move it upward against the compression force of the spring 22'. At the preset cutoff pressure this upward displacement becomes sufficient to cause valve member 19' to close off the valve seat 21'. This cuts off further air flow into the tyre. If tyre pressure subsequently falls below the preset pressure the piston 8' moves downwardly under the compression force of spring 22' and the valve 19' opens in preparation for filling. During these operations the indicator band 18' and viewing cap 7' operate in a similar manner to the first embodiment. WO 2004/030952 PCT/AU2003/001283 -9- A further feature of this second embodiment is an over-ride mode which is obtained by turning the cap 7' completely down onto the threads 38 so as to display a coloured (e.g. yellow) ring 39. This procedure also simultaneously conceals the band 18' behind an opaque upper portion 40 of the cap 7' and holds said band and connected piston assembly 18' down to the open position irrespective of tyre pressure. In this mode the device can be operated via the schrader valve 11' and the tyre inflated to any desired pressure. Preferably the ring 39 is also adapted to function as a moisture/dust seal or secondary gas seal in the event of leakage past primary cup seal 16'. For installation the threaded sleeve 3' of this embodiment is fitted through aperture 4A' of the wheel rim 5A1 and is held in place by a lock nut 41 of any suitable design. There is also a rubber grommet 42 fitted under the lock nut for sealing purposes. It will thus be appreciated that this invention at least in the form of the embodiment disclosed provides a novel and useful improvement to vehicle tyre valves. Clearly however the example described is only the currently preferred form of the invention and a wide variety of modifications may be made which would be apparent to a person skilled in the art. For example the shape and configuration of the transparent cap and the preset cutoff pressure may be WO 2004/030952 PCT/AU2003/001283 -10- changed according to application. Also while it is currently preferred to construct the valve and housing from a corrosion resistant metal such as brass the invention extends to the use of any other suitable material. For the purposes of this specification expressions such as "top", "bottom", "below", "upper" and "lower" etc refer to the valve housing in one position of use as illustrated are are not to be taken as necessarily limiting. WO 2004/030952 PCT/AU2003/001283 -11- The claims: 1. Apparatus for regulating air flow into a rim mounted pneumatic vehicle tyre, said apparatus having an elongated valve housing with an inlet end, an outlet end and a central portion, the outlet end including a rim insertion portion configured to fit into an aperture in the tyre rim, a piston disposed within said housing and including a valve member, a coil spring acting between said housing and piston whereby in use of said apparatus the piston is biased to an open position for passage of air into said tyre and is movable against said bias under force of air pressure build-up in said tyre to a closed position at which the valve member seals against a valve seat to close off said passage of air wherein said piston and spring are located within said central portion of the housing clear of the rim insertion portion so that said rim insertion portion is of a reduced size not obstructive to the mounting of said tyre. 2. The apparatus as claimed in claim 1 wherein the spring acts in compression between a flange on the piston and an interior shoulder of the valve housing. 3. The apparatus as claimed in claim 2 wherein a visual indicator is fitted to the piston to show the position thereof. WO 2004/030952 PCT/AU2003/001283 -12- 4. The apparatus as claimed in claim 3 wherein the visual indicator is a band which is visible through a transparent portion of a cap fitted to the housing. 5. The apparatus as claimed in claim 4 wherein the cap can be turned down onto a threaded seat to an over-ride position whereby said band and piston are held to said open position irrespective of tyre pressure. 6. The apparatus as claimed in claim 5 wherein said cap includes an opaque portion which conceals said band when the cap is turned down to said over-ride position. 7. The apparatus as claimed in claim 7 wherein at said over-ride position a coloured ring is displayed through said transparent portion of the cap. 8. The apparatus as claimed in claim 7 wherein said ring also functions as a moisture/dust seal or a secondary gas seal in the event of leakage past a primary seal in said valve housing. 9. The apparatus as claimed in claim 8 wherein the piston is slidable along a central tube and cylinder wall in said housing, said tube being part of a sub-assembly which is connected to said housing. WO 2004/030952 PCT/AU2003/001283 -13- 10. The apparatus as claimed in claim 9 wherein the piston at an upper end thereof mounts said band and towards the lower end thereof carries said valve member shaped to form a pressure tight seal when engaged in the valve seat located at the base of said central tube. 11. The apparatus as claimed in claim 10 wherein the inlet end is fitted with a schrader valve.

Full Text

WO 2004/030952 PCT/AU2003/001283
AIR FLOW CONTROL APPARATUS
FIELD OF THE INVENTION
This invention relates to fluid control devices. More
particularly although not exclusively it discloses an
improved pressure cutoff valve for vehicle tyres.
BACKGROUND TO THE INVENTION
Correct pressure in vehicle tyres is of considerable
importance. Excessive pressure can cause premature tread
wear and loss of traction in the wet. Low pressure on the
other hand can cause loss of stability when cornering and
tyre failure from excessive wall flexing. While most
service stations provide facilities for drivers to check
their tyres the gauges are often defective or at best
inaccurate. In order to alleviate such problems valves have
been proposed for tyres which during filling automatically
cut off the air supply once a preset pressure is reached.
The user therefore does not need to be concerned about
monitoring tyre pressure during filling. Rather it is only
necessary to maintain the air hose fitting on the tyre
valve until it automatically cuts off. These valves
typically use a piston which is biased to an open position
by a compression spring during filling but is moved against
said bias to a closed position when an applied force from
the internal tyre pressure reaches a preset amount of say
200 kpa. Existing valves have the disadvantage however that
the compression spring and piston are located in the base
of the valve assembly which is therefore enlarged and

WO 2004/030952 PCT/AU2003/001283
-2-
protrudes a substantial distance through into the interior
of the tyre rim. This obstructs the fitting of the tyre and
can result in the base of the valve housing being damaged
during initial inflation as the tyre bead expands onto the
rim.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to ameliorate
the aforementioned disadvantage and accordingly a apparatus
for regulating air flow into a rim mounted pneumatic
vehicle tyre is disclosed, said apparatus having an
elongated valve housing with an inlet end, an outlet end
and a central portion, the outlet end including a rim
insertion portion configured to fit into an aperture in the
tyre rim, a piston disposed within said housing and
including a valve member, a coil spring acting between said
housing and piston whereby in use of said apparatus the
piston is biased to an open position for passage of air
into said tyre and is movable against said bias under force
of air pressure build-up in said tyre to a closed position
at which the valve member seals against a valve seat to
close off said passage of air wherein the piston and spring
are located within said central portion of the housing
clear of the rim insertion portion so that said rim
insertion portion is of a reduced size not to obstruct the
mounting of said tyre.
Preferably said piston is fitted with a visual indicator to

WO 2004/030952 PCT/AU2003/001283
-3-
show position.
It is further preferred that said spring acts in
compression between a flange on the piston and an interior
shoulder of the valve housing.
It is further preferred that the visual indicator is a band
which is visible through a transparent portion of a cap
fitted to the housing.
It is further preferred that the cap is adapted to be
turned down onto a threaded seat to an over-ride position
whereby said band and piston are held to said open position
irrespective of tyre pressure
It is further preferred that the valve housing be fitted
with a schrader type one way valve at the inlet end.
BRIEF DESCRIPTION OF THE DRAWINGS
Two currently preferred embodiments of this invention will
now be described with reference to the attached drawings in
which:-
figure 1 is a perspective side view of an automobile
tyre valve according to the invention,
figure 2 is a vertical cross-sectional of the valve
of figure 1 when in the open position, and

WO 2004/030952 PCT/AU2003/001283
-4-
figure 3 is a cross-sectional view along the lines
A-A of figure 1,
figure 4 is a cross-sectional view similar to
figure 2 but with the valve in the closed
position, and
figure 5 is a cross-sectional view of a spring
tension adjustment plug which can be
fitted to the valve of figure 1, and
figure 6 is a vertical cross-sectional view of a
second embodiment of an automobile tyre
valve according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to figures 1 and 2 the valve housing 1 may
comprise an elongated cylindrical casing with an inlet 1A
at the top as shown and an outlet 2 at the bottom. The
outlet end of the housing preferably comprises an insertion
sleeve 3 with a groove 4 and shoulder 5 which adapt said
sleeve for fitting through an aperture 4A in a pneumatic
tyre rim 5A. Preferably the outlet end is moulded from
rubber or other suitable material to obtain the necessary
pressure tight seal to the rim. At the inlet end 1A there
is a short pipe section 6 of reduced diameter to connect
with an air supply hose nozzle such as that provided at
service stations. Immediately below this is a transparent
cap 7 through which the position of an internal indicator
band (which may be coloured red) can be viewed as described
later.

WO 2004/030952 PCT/AU2003/001283
-5-
Referring more specifically to figures 2 and 3 there is a
piston 8 which is longitudinally slidable between the
housing cylinder wall 9 and a central tube 10. The tube 10
is part of a sub-assembly which includes the pipe 6 with a
schrader type inlet valve 11 of known construction. This
sub-assembly is threaded into or otherwise rigidly
connected to the housing at 12. The transparent cap 7 also
fits onto the housing at this location and provides a view
window between the top of said housing 12A and the pipe 6.
As the pipe 6 and housing are fixed relative to one another
this cap 7 takes no load and can therefore be of
nonstructural material such as a low cost plastic. There
are 0-rings 13, 14 fitted to provide a sliding pressure
tight fit between both the outside of piston 8 and cylinder
9 as well as the internal piston bore 15 and tube 10.
Preferably a directional low friction cup seal 16 may also
be fitted into a nich 17 in the piston immediately below 0-
ring 13 to further ensure against air leakage between the
piston and cylinder. The piston 8 at its upper end mounts
the indicator band 18 and towards the lower end the bore 15
is fitted with a valve member having a bevelled head 19 and
upwardly directed needle 20. The needle extends up through
a seat 21 formed at the base of tube 10. The seat is shaped
to form a pressure tight seal when engaged by the bevelled
head 19 of the valve member. There is also a tension spring
22 which acts between a transverse pin 23 located across
the housing just above the insertion sleeve and the centre

WO 2004/030952 PCT/AU2003/001283
-6-
24 of the piston. Preferably the spring at one end hooks
over pin 23 and at the other end seats in spiral grooves
around the centre of the piston. In figure 2 the piston is
held to its lowermost position where the band 18 abuts the
top of the housing. In accordance with this invention it
will be noted that the tension spring 22 and piston 8 move
within the centre portion of the housing above the
insertion sleeve 3. This allows the rim insertion sleeve at
the outlet end to be greatly reduced in diameter and
length. It therefore provides virtually no obstruction to
the tyre bead during initial mounting and inflation of said
tyre on the rim. The moulded rubber construction of the
insertion sleeve with the current embodiment also allows
the housing 1 to flex relative to the tyre rim to reduce
the chances of breakage.
In the open position of figure 2 a supply of pressurised
air is able to flow through the inlet schrader valve 11,
down through tube 10, around open valve member 19, through
ports 26, along clearance space 27 between the spring 22
and housing to enter the tyre (not shown) through outlet 2.
As the pressure inside the tyre builds up however a force
(arrow B) acts against the underside of the piston moving
it upward. At a preset cutoff pressure of say between 80
and 1000 kpa determined by the underside area of the piston
8, the deflection constant of the spring 22 and the
position of valve seat 21 the upward displacement of the

WO 2004/030952 PCT/AU2003/001283
-7-
piston 8 causes the valve head 19 to close into said seat
as shown in figure 4. This cuts off further air flow into
the tyre. It will also be noted from figure 4 that the band
18 simultaneously moves upward within transparent cap 7 to
indicate that the preset pressure has been reached in the
tyre and the cutoff valve 19 is closed. If tyre pressure
subsequently falls below this preset pressure the piston
and indicator band 18 move downwardly under the tension
force of spring 22 to show low pressure and the valve 19
opens in preparation for filling. Leakage of air out of the
tyre however is prevented by the one way operation of the
schrader valve 11 which only allows discharge through
deliberate depression of insert stem 28.
As an alternative to the fixed transverse pin 23 for
holding the lower end of the spring 22 a threaded anchor
plug 29 as shown in cross-section by figure 5 may be turned
into the housing at the same location. This plug has an
upstanding pin 30 with a circumferential groove 31. The
lower end of the spring is then shaped to seat in this
groove so that rotation of the plug using an alien key or
the like on socket 32 adjusts the spring tension and thus
the cutoff pressure of the valve. A series of apertures 33
around the periphery of the plug allows air to pass through
to the outlet 2.
With the second embodiment of the invention shown in figure

WO 2004/030952 PCT/AU2003/001283
8
6 the main items that correspond in function to those of
figures 1, 2 and 4 are indentified by the same
numbers/letters which are however primed (') to distinguish
them.
In this case the spring 22' is still located well clear of
the rim insert portion 3' but now acts in compression
between a circular flange 35 near the bottom of the piston
8' and an interior shoulder 36 of the valve housing 1'. A
cup seal 36A is also fitted in place of the inner o-ring 14
of the first embodiment. With the valve in the open
position shown the piston 8' is held down by the spring 22'
so that air can flow through the inlet schrader valve 11',
down through the tube 10', past the open valve seat 21' and
through ports 37 to enter the tyre via outlet 2'. As
pressure within the tyre builds up a force (arrows B') acts
against the underside of the piston 8' to move it upward
against the compression force of the spring 22'. At the
preset cutoff pressure this upward displacement becomes
sufficient to cause valve member 19' to close off the valve
seat 21'. This cuts off further air flow into the tyre. If
tyre pressure subsequently falls below the preset pressure
the piston 8' moves downwardly under the compression force
of spring 22' and the valve 19' opens in preparation for
filling. During these operations the indicator band 18' and
viewing cap 7' operate in a similar manner to the first
embodiment.

WO 2004/030952 PCT/AU2003/001283
-9-
A further feature of this second embodiment is an over-ride
mode which is obtained by turning the cap 7' completely
down onto the threads 38 so as to display a coloured (e.g.
yellow) ring 39. This procedure also simultaneously
conceals the band 18' behind an opaque upper portion 40 of
the cap 7' and holds said band and connected piston
assembly 18' down to the open position irrespective of tyre
pressure. In this mode the device can be operated via the
schrader valve 11' and the tyre inflated to any desired
pressure. Preferably the ring 39 is also adapted to
function as a moisture/dust seal or secondary gas seal in
the event of leakage past primary cup seal 16'.
For installation the threaded sleeve 3' of this embodiment
is fitted through aperture 4A' of the wheel rim 5A1 and is
held in place by a lock nut 41 of any suitable design.
There is also a rubber grommet 42 fitted under the lock nut
for sealing purposes.
It will thus be appreciated that this invention at least in
the form of the embodiment disclosed provides a novel and
useful improvement to vehicle tyre valves. Clearly however
the example described is only the currently preferred form
of the invention and a wide variety of modifications may be
made which would be apparent to a person skilled in the
art. For example the shape and configuration of the
transparent cap and the preset cutoff pressure may be

WO 2004/030952 PCT/AU2003/001283
-10-
changed according to application. Also while it is
currently preferred to construct the valve and housing from
a corrosion resistant metal such as brass the invention
extends to the use of any other suitable material.
For the purposes of this specification expressions such as
"top", "bottom", "below", "upper" and "lower" etc refer to
the valve housing in one position of use as illustrated are
are not to be taken as necessarily limiting.

WO 2004/030952 PCT/AU2003/001283
-11-
The claims:
1. Apparatus for regulating air flow into a rim mounted
pneumatic vehicle tyre, said apparatus having an
elongated valve housing with an inlet end, an outlet end
and a central portion, the outlet end including a rim
insertion portion configured to fit into an aperture in
the tyre rim, a piston disposed within said housing and
including a valve member, a coil spring acting between
said housing and piston whereby in use of said apparatus
the piston is biased to an open position for passage of
air into said tyre and is movable against said bias under
force of air pressure build-up in said tyre to a closed
position at which the valve member seals against a valve
seat to close off said passage of air wherein said piston
and spring are located within said central portion of the
housing clear of the rim insertion portion so that said
rim insertion portion is of a reduced size not
obstructive to the mounting of said tyre.
2. The apparatus as claimed in claim 1 wherein the spring
acts in compression between a flange on the piston and an
interior shoulder of the valve housing.
3. The apparatus as claimed in claim 2 wherein a visual
indicator is fitted to the piston to show the position
thereof.

WO 2004/030952 PCT/AU2003/001283
-12-
4. The apparatus as claimed in claim 3 wherein the visual
indicator is a band which is visible through a
transparent portion of a cap fitted to the housing.
5. The apparatus as claimed in claim 4 wherein the cap
can be turned down onto a threaded seat to an over-ride
position whereby said band and piston are held to said
open position irrespective of tyre pressure.
6. The apparatus as claimed in claim 5 wherein said cap
includes an opaque portion which conceals said band when
the cap is turned down to said over-ride position.
7. The apparatus as claimed in claim 7 wherein at said
over-ride position a coloured ring is displayed through
said transparent portion of the cap.
8. The apparatus as claimed in claim 7 wherein said ring
also functions as a moisture/dust seal or a secondary gas
seal in the event of leakage past a primary seal in said
valve housing.
9. The apparatus as claimed in claim 8 wherein the piston
is slidable along a central tube and cylinder wall in
said housing, said tube being part of a sub-assembly
which is connected to said housing.

WO 2004/030952 PCT/AU2003/001283
-13-
10. The apparatus as claimed in claim 9 wherein the
piston at an upper end thereof mounts said band and
towards the lower end thereof carries said valve member
shaped to form a pressure tight seal when engaged in the
valve seat located at the base of said central tube.
11. The apparatus as claimed in claim 10 wherein the
inlet end is fitted with a schrader valve.

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Patent Number

213632

Indian Patent Application Number

00609/KOLNP/2005

PG Journal Number

02/2008

Publication Date

11-Jan-2008

Grant Date

09-Jan-2008

Date of Filing

08-Apr-2005

Name of Patentee

SAMPSON RONALD SPENCER

Applicant Address

84 WARRAH ROAD, YOWIE BAY, NEW SOUTH WALES 2228,

Inventors:

#	Inventor's Name	Inventor's Address
1	SAMPSON RONALD SPENCER	84 WARRAH ROAD, YOWIE BAY, NEW SOUTH WALES 2228,

PCT International Classification Number

B60C 29/00

PCT International Application Number

PCT/AU2003/001283

PCT International Filing date

2003-09-30

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2002301269	2002-10-01	Australia