Aerosol container valve with means for tapping additional gas

The container valve housing is provided with two concentric bearing walls having different heights, the outer bearing wall being fitted with a gasket which is traversed by the valve stem and the inner bearing wall being applied against the gasket so as to form an internal chamber which communicates with the product to be dispensed. An annular wall between the two bearing walls is provided with filler openings and with at least one independent calibrated bleeder orifice or tap for the admission of propellant gas from the headspace of the container into the internal chamber.

This invention relates to the pressurized packaging industry and 
specifically to the packaging of fluid substances. 
Valves for tapping additional gas are already known and have the effect of 
improving spray discharge properties, especially when the propellant 
consists of butane, propane or a similar gas. 
In a typical valve described in U.S. Pat. No. 3,225,969 to O'Donnel, the 
additional gas tap or bleeder orifice is partially defined by the gasket. 
In valves of this type, the spray discharge properties vary to a 
considerable extent according to the rate of flow of additional gas 
admitted or more specifically according to the cross-sectional area 
provided for the gas flow. It would therefore appear feasible to remove 
this objection simply by means of valves designed to provide 
cross-sectional areas of optimum value for the flow of additional gas. The 
problem which arises in actual practice, however, lies in the fact that 
variations are introduced by sealing gaskets of elastic material, both in 
the assembly of the valves and as a result of mechanical degradation of 
gaskets in time and possible swelling of these latter in contact with 
packaged products. 
The disadvantage attached to known valves of this type is that they have 
different characteristics from one valve to another and that the desired 
optimum standard of operation cannot be ensured at the time of 
manufacture. Moreover, the structure of such valves does not permit of 
rapid admission for filling the container. 
The primary aim of the present invention is to overcome the disadvantages 
mentioned in the foregoing. 
The invention is accordingly concerned with an aerosol container valve with 
an additional-gas tap, a valve stem being displaceable by hand in 
opposition to a restoring spring from a closed position to a temporarily 
open position. The valve essentially comprises a cup to be crimped on the 
container in order to maintain a valve housing having two concentric 
annular bearing walls which are relatively displaced in height. The outer 
bearing wall is applied directly against said valve cup and contains a 
gasket which is traversed by the valve stem. The inner bearing wall of the 
valve housing is applied against the gasket and forms within said housing 
a chamber which communicates with the product to be dispensed. The annular 
wall between the two bearing walls is pierced on the one hand by a 
plurality of openings for filling the container by means of a flow which 
passes around the gasket and the internal chamber of the valve housing and 
on the other hand by at least one calibrated orifice for the flow of 
propellant gas from the headspace of the container into said internal 
chamber. 
In accordance with the invention, arrangements are advantageously made to 
bring the additional gas as close as possible to the bottom face of the 
gasket with a view to achieving enhanced valve performance. To this end, 
the calibrated orifice opens into a separate admission chamber defined 
between the two bearing walls of the valve housing whilst two transverse 
walls extend between said bearing walls and the gasket. The admission 
chamber communicates with the valve housing chamber through a port formed 
in the inner bearing wall between the radial walls. The cross-sectional 
area for flow through said port is much greater than that of the 
calibrated orifice for the propellant gas. 
In order to obtain rapid filling of aerosol containers, it appears 
desirable to ensure that the valve is provided with a plurality of 
openings. The valve advantageously has five filler openings uniformly 
spaced along the same circumference between the two annular bearing walls.

The valve illustrated in FIGS. 1 to 3 essentially comprises a housing 1 
crimped within a valve cup 2 with interposition of a gasket 3 of 
conventional type for aerosol containers. 
The valve housing 1 is provided with two concentric bearing walls 4, 5 
having different heights. The gasket 3 is contained laterally and centered 
by the outer bearing wall 5 whilst the inner bearing wall 4 is applied 
against said gasket 3 in leak-tight manner. 
The gasket 3 is traversed by the tubular valve stem 6 which is urged to the 
closed position of the valve (FIG. 1) by a restoring spring 7. The valve 
stem 6 can be displaced by hand in opposition to the spring 7 to a bottom 
position in which the valve is open, either for the purpose of dispensing 
the product or for the purpose of filling the container (FIG. 3). 
A conventional actuator button with spray discharge nozzle (not shown in 
the drawings) is fitted on the valve stem 6 for dispensing the product 
contained in the pressurized pack. 
The internal chamber 8 of the valve housing 1 communicates with the product 
to be dispensed through a dip tube 9 with interposition of a flow-reducer 
10 (this feature being optional). 
The annular wall of the valve housing 1 between the two concentric walls 4 
and 5 is pierced by: 
(a) Five filler openings 11 of oblong shape which are uniformly spaced 
along the same circumference between the two annular bearing walls; 
(b) A calibrated orifice 12 for admitting the propellant gas which 
constitutes additional gas and is contained within the free internal space 
or so-called headspace of the container. 
As shown in FIGS. 1 and 2, the calibrated orifice 12 opens into an 
admission chamber 13 formed between the bearing walls 4, 5 by two 
transverse walls 14, 15 beneath the gasket 3. A port 20 cut in the edge of 
the inner bearing wall 5 establishes a communication between the admission 
chamber 13 and the valve housing chamber 8. 
The gasket 3 is centered in the outer bearing wall 4 by means of a 
plurality of bosses 16 spaced between the filler openings 11 so as to 
define a free space opposite to each opening. Bosses 16 are intended to 
ensure centering of gasket 3 and to permit the flow of propellant gas 
between the spaces formed by the intervals between bosses 16 for the 
purpose of filling a container fitted with the valve. 
In order to fill a container which is fitted with a valve of this type, the 
nose 17 of the filling machine is first brought into position (as shown in 
FIG. 3) against the valve cup 2 with interposition of an O-ring seal 18 
and the valve stem 6 is displaced downwards to its bottom position 
(valve-opening position). The product which is injected under pressure 
flows rapidly in the direction shown by the arrows F through the opening 
formed by the annular flange which surrounds the valve stem, passes around 
the gasket 3 and penetrates into the container through the openings 11. To 
a lesser extent, the product under pressure is also admitted into the 
container through the valve proper as shown by the arrows G, that is to 
say through the tubular valve stem 6, through the flow passage 19 pierced 
in said stem, through the internal chamber 8 of the valve housing and 
through the dip tube 9. 
Once the container has been filled, a conventional hand-operated actuator 
button with or without spray discharge nozzle is fitted on the valve stem 
6. 
When the actuator button is depressed, the product under pressure is 
dispensed as follows: 
(a) in the case of the liquid phase: through the dip tube 9, the valve 
housing chamber 8, the flow passage 19 and the tubular valve stem 6; 
(b) in the case of the gas phase (propellant gas within the container): 
through the calibrated orifice 12, the admission chamber 13, the valve 
housing chamber 8 in the vicinity of the gasket 3, the flow passage 19, 
the tubular valve stem 6. 
In fact, the flow path which is common to both phases begins at the top 
portion of the valve housing chamber 8 and continues with the flow passage 
19 and the valve stem 6. 
As can readily be understood, the invention is not limited to the 
embodiment hereinabove described with reference to the accompanying 
drawings. Depending on the applications which are contemplated, 
consideration can accordingly be given to many alternative forms of 
construction without thereby departing either from the scope or the spirit 
of the invention.