Pressurized Fluid Dispensing Container

Abstract

A pressurized fluid dispensing container, in which a fluid pressure vessel is positioned in an outer container and carries an outlet valve at its upper end. The lower end abuts, preferably via a pressure piece which may be threadably adjustable, the bottom wall of the vessel, while the outlet valve is located adjacent the outer container lid, so that, should said vessel expand axially due to increase in temperature, the valve is depressed, releasing some of the fluid. The quantity of fluid in the vessel may be measured by a spring balance arrangement.

Description

The present invention relates to a pressurized fluid dispensing container.

Aerosol cans having an inner vessel for the pressurised fluid, with a valve at the top, and an outer containr have found acceptance in many fields for spraying liquids or for blowing compressed gas contained therein. They are used, for example, for spraying paints, for spraying cosmetics or for producing a flow of gas in injectors. If liquids are to be sprayed, then they are under the pressure of a compressed propellant gas contained in the inner vessel. If a stream of gas is to be produced, the gas which issues as a rule represents the sole medium contained in the inner vessel.

Since gases are known to possess a very high thermal coefficient of expansion, the vessels containing compressed gas must not be warmed above certain temperatures which are relatively little above room temperature, if the danger of an explosion is to be excluded. For this reason, all aerosol cans as a rule carry a printed note that the cans should be prevented from rising in temperature to above a certain limit. Such rises in temperature cannot, however, always be avoided. Thus it frequently happens that temperatures of 70.degree. C and above are measured in the boot or in the interior of a motor vehicle which has been parked in the sun. On beaches with very intense sunshine the temperature rise in beach bags or the like can be so great that the permissible temperature limit for cosmetic aerosol cans contained therein are exceeded. The aerosol bottles which are used in respiration equipment and life-saving equipment on beaches, such as disclosed in my U.S. Pat. No. 3,665,919 entitled "Section Apparatus," can also not always be protected effectively against an impermissible rise in temperature.

According to the present invention, there is provided a pressurised fluid dispensing container comprising an outer container having an internal abutment spaced from the bottom wall thereof, a pressurized fluid vessel mounted within said outer container, the lower end of the fluid vessel directly or indirectly abutting the bottom wall of the outer container and an axially operable outlet valve at the upper end of the vessel adjacent the abutment member, whereby, upon axial expansion of the pressurized fluid vessel due to increase in pressure of the fluid, the outlet valve is opened by abutment with the abutment member to release some of the fluid.

The abutment member may take any suitable form such as a bridge extending across the interior of the outer container, but preferably it is simply the lid of the outer container, and this may be removable.

With the construction of the invention, should the rise in temperature exceed the permissible limits, an elastic deformation of the vessel takes place before the explosive limit is reached. This elastic deformation is employed to displace the entire vessel in the direction of the lid of the container and hence to actuate the valve which rests directly, or almost rests, against the lid of the container. As a result, the gas which is under dangerous pressure escapes and reduces the pressure prevailing in the interior of the vessel.

As a rule, the escape of the gas or the liquid to be sprayed results in a considerable cooling, because of the expansion of the propellant gas, and this contributes to a further reduction in pressure. As a result of the container being designed so as to correspond to the dimensions of the vessel, the valve located on the vessel acts as a safety valve without special additional devices.

Aerosol cans as a rule possess a bottom which is domed inwards. In such a case, according to a further feature of the invention, a pressure piece is interposed between the bottom of the container and the lower end of the vessel. This pressure piece is suitably fixed to the bottom of the container. In a particularly advantageous embodiment, this pressure piece can be screwed into the bottom of the container. This permits one's own adjustment to ensure in each case that the valve rests against the lid of the container.

In order that the invention may more readily be understood, the following description is given, merely by way of example, reference being made to the accompanying drawings, in which:

FIG. 1 is a longitudinal section through one embodiment of container according to the invention, which is employed in conjunction with an artificial respiration apparatus, and

FIG. 2 shows a further embodiment of a container according to the invention .

FIG. 1 shows a suction apparatus similar to that disclosed in my U.S. Pat. No. 3,665,919, which consists essentially of an outer closable container 1, for an inner pressurized fluid vessel 2, an injector 3 and a collector vessel 4 connected to the injector 3.

The vessel 2 has, at its upper end, an axially actuatable outlet valve 5, which rests against the injector 3 and can be pressed in through an axial displacement of the pressurized vessel 2. The axial displacement of the vessel 2 is made possible by a pressure piece 6 which is connected to a rotating knob 8 screwed into the bottom 7 of the container 1. The pressure piece 6 here acts on the concave bottom 9 of the vessel 2.

Around the pressure piece 6 there is a helical spring 10 which rests on the bottoms 7 and 9 of the container 1 and of the vessel 2, respectively.

The suction apparatus shown in FIG. 1, the detailed description of which is disclosed in my U.S. Pat. No. 3,665,919, is part of the first aid equipment for use at swimming baths or on beaches. If now, as a result of sunshine or the like, the temperature of the vessel 2 rises too much, a considerable increase in pressure of the gas contained therein results, and this in turn causes an elastic deformation of the sheet-metal vessel 2. The greatest deformation here occurs at the concave bottom 9 of the vessel 2. As a result of this deformation, the entire vessel is pushed in the direction of the valve 5, the latter is pressed into the injector 3, and hence gas is released. As a result, the pressure in the vessel 2 drops, and the cooling resulting from the escape of gas additionally assists the reduction in pressure as a result of a drop in temperature.

In the embodiment shown, the pressure piece 6 is made axially adjustable through screwing in the rotating knob 8 which at the same time serves to actuate the valve 5. Furthermore, the injector 3 serves as a lid for the container 1. However, considerably simpler arrangements are also possible. For example, the injector 3 may be replaced by an ordinary screw lid and the adjustable pressure piece 6 may be replaced by a pressure piece which is permanently fixed to the bottom 7 of the container 1. In this case the length of the container 1 must beforehand be so adjusted to the length of the vessel 2, that the pressure piece rests against the bottom of the vessel and the valve rests directly, or almost rests, against the lid. By choosing a screw lid, however, individual adjustment of these length conditions can also be achieved in this case, so that unavoidable tolerance variations can be compensated.

FIG. 2 shows an embodiment of a container according to the invention which substantially corresponds to the container 1 represented in FIG. 1 and therefore like parts have been given the same reference numbers. The container 1 is shown without a lid. It once again holds a vessel 2 having a valve 5 at its upper end. A spring is provided between the bottoms 7 and 9 of the container 1 and the vessel 2, respectively. On the outer wall of the vessel 2 there is a scale 12, running axially, and cooperating with a marking 13, in the shape of an arrow, on the container 1. The position and calibration of the scale 12 is so adjusted to the marking 13 or the stiffness of the spring 11 that with the lid removed, the weight of the vessel 2, that is to say the weight of the contents, can be determined from the relative position of the scale 12 and the marking 13. The calibration of the scale 12 is conveniently given in percentage degrees of filling. Of course any other scale unit which appears suitable can be used.

In the embodiment shown in FIG. 2, the container 1 is transparent. If the container consists of an opaque material it is convenient to provide, in place of the arrow marking 13, an aperture for taking a reading, through which the scale 12 can be observed. In this case either the scale 12 is provided over the entire periphery of the pressurized vessel 2, or several such apertures for taking a reading are formed in the container 1, in order to ensure that the scale 12 can be read even if the pressurized vessel 2 is rotated relative to the container 1.

As shown in FIG. 1, a further spring 14 is provided at the upper, valve-side, end of the pressurized vessel 2, acting against the lower spring 10. This spring 14 can be employed to balance the springiness of the spring 10 if, in order to save cost, the pressure piece 6 is to be dispensed with and the spring 10 is to assume its role. If then the lid is closed, the valve 5 is freed by the spring 14 of the force of the spring 10, so that the valve cannot be pressed in. If, on the other hand, the temperature of the vessel 2 rises to an impermissible extent, the concave bottom 9 of the vessel 2 deforms outwards, compresses the lower spring 10 and hence pushes the vessel 2 against the lid, and presses in the valve 5, in the manner already explained above.

In the embodiments shown in FIGS. 1 and 2, spiral springs are shown as the springs. However, for particularly cheap and simple embodiments leaf springs can in particular be used, which can easily be fixed to the bottom of cardboard containers or other containers and which, as regards their mode of action, are identical to the spiral springs described above.

As shown in FIG. 1, an annular electrical battery 15 is provided at the upper end of the container 1, and feeds, via leads 16, a heating coil 17 placed around the valve end of the vessel 2. This arrangement makes it possible to compensate for severe cooling of the vessel 2 which occurs when the gas escapes; this cooling in many cases results in the pressure in the pressurized vessel dropping very greatly, the speed of escape of the gas hence declines, and as a consequence thereof the suction action of the injector 3 (as described in detail in my U.S. Pat. No. 3,665,919) is considerably impaired. In order to improve the heating effect it is advisable to choose the material of which the jacket of the vessel 2 is made so as to be a good conductor of heat. For practical purposes, aluminium, which is in any case used in most instances, is suitable.

Of course, the heating coil 17 should only come into operation if the escape of gas is to be initiated manually, that is to say not in the emergency case explained above. For this purpose, the leads 16 can be controlled from the rotating knob 8 via a switch which is not shown.

Claims

I claim:

1. A pressurized fluid dispensing container comprising, in combination: an outer container; a bottom wall at the lower end of the outer container; an internal abutment member spaced from the lower end of the container forming a removable lid of the outer container; a pressurized fluid vessel mounted within the outer container; a lower end of the vessel abutting the bottom wall of the outer container; a spring located between the bottom wall of the container and the lower end of the pressurized fluid vessel; markings on the vessel and container to indicate the compression of the spring and thus the degree of filling of the vessel; and an axially operable outlet valve at the upper end of the vessel adjacent the abutment member, whereby, upon axial expansion of the pressurized fluid vessel due to increase of temperature of the fluid, the outlet valve is opened by abutment with the abutment member to release some of the fluid.

2. A container as claimed in claim 1 wherein the lower end of the vessel is domed inwards; and further comprising a pressure piece interposed between the lower end and the bottom wall of the container.

3. A container as claimed in claim 2, wherein the pressure piece is threaded to the bottom wall of the container, and further comprising an actuating knob carried by the pressure piece externally of the bottom wall for the axial displacement of the vessel and actuation of the valve.

4. A container as claimed in claim 1 further comprising a second spring disposed between the upper end of the vessel and the abutment member.

5. A container as claimed in claim 1, wherein the marking on the vessel is a scale thereon, and further comprising means defining at least one aperture in the container in front of the scale for taking a reading.

6. A container as claimed in claim 1 further comprising a lid for the container, an injector positioned in the lid to receive the outlet valve, and a collector vessel in the lid connected to the injector.