GB2109869A - Dispensing container - Google Patents

Abstract

A pressurisable dispensing container comprises a steel can (10) of a kind capable of holding substantial internal pressure, and a pressurising unit (50) secured removably or permanently, in a hole in the top end member (18) of the can. The unit (50) may be an adaptor to enable a pump to be attached to apply internal pressure which drives the can contents out through an outlet (46) passing through the same hole in the can end. Alternatively the pump may be an integral part of the pressurising unit. <IMAGE>

Description

SPECIFICATION Dispensing containers This invention relates to dispensing containers for flowable products, such containers comprising a steel can, capable of withstanding internal pressure and being of the kind comprising a cylindrical body shell and an end member secured over each end of the shell.

"Steel" in this specification means steel of a thickness and quality such as is commonly used for disposable cans of the so-called "open top" type or for aerosol dispensing cans, and include tinplate, blackplate, "tin-free steel" and stainless steel.

Pressurisable steel cans for dispensing liquids are well-known in the form of, for example, beer and beverage cans having at one end a can end member of the so-called easy-opening or selfopening type in which a pull tab is pulled by the consumer to fracture the end member along a line of weakening or score line and so open the container. Such containers are pre-pressurised, in that the can is charged with product under pressure and the end member is then attached whilst the can is still under pressure. The pressure is released when the can is opened, and the product is dispensed under atmospheric pressure, through the opening formed by tearing the line of weakening.

Other forms of pressurisable steel cans for dispensing liquids include cans similar to the above but having a plain end member which has to be opened, in order to release the internal pressure and allow the contents to be poured out, by means of a separate tool such as a can opener.

In another form, a steel can has a hole closed by a bung, or two holes closed by bungs, the bung or bungs being removable so as to release the internal pressure and allow the contents to be poured, again under atmospheric pressure. All these arrangements, again, require prepressurisation.

A further type of dispensing container, capable in this case of pressurisation to considerable levels, is the well-known aerosol can, which has to be of special construction and requires a special dispensing valve whereby, upon the valve being operated, the product within the can mixes with a propellant gas, contained in the can, whose pressure causes the resulting mixture to be forced out through the valve. The product itself is in liquid form but may be of relatively high viscosity (e.g. paints or toothpaste). Aerosol dispensing containers are generally suitable only for dispensing the products in the form of a spray or foam, and, whilst very convenient in many applications, are comparatively expensive in terms of non-reusable commitment of the materials used for the various components.This is not only because of the need to construct the aerosol can so robustly, but also because it has to be filled by means of special equipment and because it requires a special propellant gas.

Again, aerosol containers require to be prepressurised.

There is a need for an inexpensive container for dispensing, under pressure, flowable products such as liquids or powders, the container being of a conveniently portable size but larger than is readily or economically capable of being made with an easy-open end or in the form of an aerosol dispensing container.

Recently there has been growing interest in the application of paint by means other than conventional, hand-held tools such as brushes, rollers etc which must be charged with paint by hand, and which therefore not only waste time (since the painting operation has to stop every time the brush or roller is recharged with paint), but which also waste paint because the paint container must be opened before painting begins and invariably there is spillage and/or oxidation of paint, and/or dripping of the paint. Conventional spraying systems, using an air compressor or highpressure gas bottle as pressurising source, are high in capital cost, high in operating cost, and cumbersome to use.

The disadvantages of spillage, spoilage and time wastage are largely eliminated by a painting system of the kind in which the paint container is never fully opened, and the paint being applied through a hermetically-sealed apparatus to a brush, pad or roller by means of gas pressure provided by a small bulb of liquid carbon dioxide.

The paint container is of a specially-designed kind having a very small hole in its lid, the lid never needing to be removed. The small hole, normally closed by a replaceable plug, is opened by removal of this plug, and the container is placed in an outer container which is then sealed by a cover which carries a dip tube, extending through the small hope in the inner paint container lid into the paint itself. The dip tube leads through suitable valve means and tubing to a duct extending through the handle of the brush, roller or pad; and the cover of the outer container also contains the gas bulb which drives the paint from the inner container to the brush, roller or pad.

Such painting apparatus is extremely attractive for the reasons mentioned above, for example, one litre of paint can thereby be made to cover an area 25% or more greater than if conventional hand painting were employed; and painting need not stop to dip a brush in the paint; and the apparatus is light and convenient to carry. It does however require the paint to be packed in the special containers having the small hole and plug in the lid. These containers must be of suitable size to fit in the outer container, which in practice restricts them to a single size. The need for an outer container, and the fact that the inner container has to be of a special design, contribute towards relatively high cost, not only of the equipment but also the paint itself as far as the user is concerned.

Another factor contributing towards high operating cost is the necessity to provide not only paint in special containers, but also the gas bulbs, which are themseives not inexpensive and which must be replaced when empty.

There is accordingly a need for an inexpensive method of painting using gaseous pressure to force the paint through the brush, roller or pad, in which a standard type of container may be employed and which does not require the purchase of pre-pressurised gas. Use of a standard container would enable the paint to be sold at lower prices than is the case with paint packed in the special containers mentioned above.

Furthermore it is desirable to eliminate the need for an outer container, i.e. to enable the equipment to be attached direct to the paint container itself, thus permitting paint containers of varying sizes to be used if desired.

It should be noted that the above desiderata doe ndt pre-suppose that the standard container which is envisaged is necessarily a container of a type commonly used for paint, but rather a container standard within the context of packaging generally, whether or not hitherto usually used for the packing of paint.

According to the invention, a dispensing container for flowable products comprises: a steel can having a cylindrical body shell and an inner member secured over each end of the shell, one of the end members having a through hole; pressurising means secured to the can and sealably closing the through hole, the pressurising means having actuating means external of the can for causing a gas to flow into the can so as to apply pressure to flowable product in the can; and delivery means terminating externally of the can for flow of the product therethrough from the can under the influence of such pressure.

The dispensing container is preferably a can of the kind commonly referred to as an open-top can. It is also of a kind capable of withstanding adequate internal pressure. The pressurising means preferably comprises a manually-operable priming pump, which may for example be of a single reciprocating plunger type, having a dip tube extending into the container.

The said one end member preferably has a single said through hole, the pressurising means and delivery means both extending through the through hole.

The upper end member or container cover may be permanently secured to the body shell of the container; this is the preferred arrangement where the container is not intended to be reusable, although the provision of the through hole does not enable the container to be refilled if required provided that, if cleaning of the interior of the container is necessary before refilling, the product previously contained in it is one that is capable of being washed out satisfactorily through the hole. Alternatively, the container may have a cover member which is secured to the body shell in a removable and re-closable manner, for example by means of a screw thread.In another example, a removable and re-closable cover member is secured by means of a resilient circumferential securing means, as for instance in the case where the cover member is a lever-lid (i.e. a lid removable by leverage exerted under a circumferential flange of the lid), the lid and container body being so designed that the force required to remove the lid is substantially greater than the resultant force exerted bun the lid by virtue of the greatest internal pressure capable of being generated by the pressurising means. In this case, where the pressurising means is manuallyoperable priming pump, the pump or the container cover member is preferably provided with a suitable safety valve for the purpose of limiting the internal pressure to a pre-determined maximum value.

An open-top tinplate can, having a nominal diameterof 5.25 inches (133 mm), and in which both end members are permanently secured by conventional double seaming to the body shell whose side seam is welded, is known and is suitable for adaption, by provision of the through hole in the upper end member, for the purposes of this invention. The can concerned is capable of withstanding internal pressures in excess of 70 psi (483 KN/m2) when the through hole is sealed in a suitable manner such that it will now lead at such pressures. However, if the dispensing container is to be used for spraying purposes the ideal operating pressure is of the order of only 40 psi (275 KN/m2).If the purpose for which the container is intended is for example to serve as a reservoir for paint, or other liquid coating material to be conducted, through the delivery means and under the influence of the internal pressure, to paint applying means such as a brush, pad or roller, the internal pressure may have a value of less or more than that quoted above in respect of spraying; but in any case such pressure would not be required to reach a value approaching the maximum value at which the container is readily capable of withstanding without leaking or bursting.

Whilst some possible practical applications of a dispensing container according to the invention have been mentioned above, it will be understood that, given the provision of suitable delivery means, it may be used for dispensing of any flowable substance whose density, and whose viscosity (in the case of liquids) or (in the case of granular or powdered solids) whose particle size is such that the substance can readily be propelled through the delivery means by the pressure generated within the container.

Where the substance to be dispensed is a water-containing liquid, the can may be fully protected by a pre-applied coating on its interior surfaces, in known manner.

Examples (given by way of non-limiting illustration) of possible practical applications of the invention include the following: (1) Garden sprays for diverse horticultural uses, for example, for weed killers, insecticides or foliar feeds.

(2) Veterinary uses such as the spraying of cow teats with anti-mastitis preparations; in this connection it should be noted that current preparations of this kind are unsuitable for containing in containers of plastics materials, being chemically incompatible with plastics.

(3) Dispensing, by spray, brush or other applicator connected to the delivery means of the container, of industrial cleaning fluids, or cleaning fluids for use in medical or chemical establishments or in laboratories; many of such fluids are, again incompatible with plastics such as might otherwise be used for containers.

(4) Dispensing of other chemicals, for example wood preservatives, woodworm or fly killers or other pesticides within building structures, or domestic cleaning fluids such as floor or window cleaners or air deodorants.

(5) Draught-proofing sealants, which may be applied in liquid form through a suitable applicator giving precise locai application.

(6) Adhesives for industrial use or by the private individual; examples include carpet or wallpaper adhesives, and wood glues of suitably relatively low viscosity.

(7) Uses in connection with food, for example application of cake decorations or icing, or ice cream toppings or syrups, particularly in catering establishments.

(8) Automotive uses, for example application of undersealing or outer body protection compounds, paint or engine cleaning compounds.

Whilst it has been suggested above that the pressurising means can comprise a manuallyoperated pump, it may for example, if desired, be of a kind in which pressure is applied to the substance contained in the container by release of air (or other suitable and compatible gas) from a bulb, cylinder or bottle containing the gaseous substance in liquid form. Alternatively the pressurising means could for example comprise a conventional automotive foot pump or bicycle pump, or a lightweight electrical compressor such as is commercially available for the purpose of inflating car tyres or for air-beds, footballs and the like.

Where the pressurising means comprises a separate pump or compressor available for other purposes, the container includes adaptor means (being part of the pressurising means of the container) to which the external pump or compressor is connected as necessary. The container may therefore include, secured sealably in the through hole in its upper end member, adaptor means in the form of a unit which includes the delivery means and, as part of the pressurising means, a non-return valve such as an automotive tyre valve, to which the pump or compressor is connectable.

The pressurising means may thus consist of a separate pump (or compressor) and adaptor means secured to the can for connection with the pump or compressor; alternatively it may consist of a single unit secured to the can, the adaptor means or single-unit pressurising means being optionally adapted to be removable from the can.

The delivery means preferably includes flow passage means extending through the adaptor or single-unit pressurising means.

The pressurising means is preferably secured to the can entirely by attachment at or through the through hole. Such attachment is obtained, in one group of embodiments, by means of a hollow fitment extending through the hole and secured to the can end member peripherally of the hole. The hollow fitment may for example be attached to the can end member by being clinched, peripherally of the fitment and of the hole. Other methods of attachment include soldering or welding. It will however, be realised that the hollow fitment may be an integral part of the can end member. At least when the pressurising means is required to be removable from the can (for example if the can is to be refillable as discussed hereinbefore), the fitment may have a screw thread.The adaptor means of the pressurising means, or the singleunit pressurising means, then has a corresponding screw thread for co-operation therewith.

Alternatively, there may be a suitable "bayonettype" attachment means for removably securing the pressurising means to the can end member.

In a preferred arrangement of such a bayonettype attachment means, the hollow fitment is a female fitment, provided with at least one radially-inwardly extending projection for engagement with a corresponding recess of the pressurising means whereby the latter can be secured to the can by insertion into the fitment and rotation to lock the projection or projections into engagement with the pressurising means.

If it is not required that the pressurising means (i.e. the adaptor means or the single-unit pressurising means) should be removable from the can, it may be permanently attached thereto.

In a preferred embodiment of such an arrangement, the pressurising means has an axial projection extending through the through hole and upset behind the through hole to secure the pressurising means sealably thereto.

Although one particular size of can has been quoted above as an example of a can suitable for use in the practice of this invention, it is to be understood that a pressurisable can of any sizeor indeed any shape-may be employed. The freedom to choose the size or shape of can, to provide the arrangement best suited to the particular practical application for which the dispensing container is intended, is an advantage of the invention over known or previouslyproposed arrangements, such as the painting apparatus described hereinbefore which requires an inner and an outer container.

Various embodiments of the invention will now be described, by way of example only, with reference to the drawings hereof, in which: Figure 1 is a somewhat diagrammatic elevation of a dispensing container, in a first embodiment according to the invention and including a can shown in diametrical section, the remainder of the dispensing container being shown in outside elevation; Figure 2 is a sectional scrap elevation showing one embodiment of means whereby the pressurising and delivery means, the former being in the form of a single unit, may be secured removably to the can; Figure 3 is a part-sectional scrap elevation as seen from the left-hand side of Figure 1, and illustrates another embodiment of means whereby the pressurising and delivery means may be securely removably to the can;; Figure 4 is a part-sectional scrap elevation which shows, in connection with a component of another type of can (illustrated by way of nonlimiting example of can types) a non-removable securing attachment of the single-unit pressurising means to the can; and Figure 5 is a further part-sectional scrap elevation, illustrating an adaptor unit of a pressurising means, and also showing another way in which the pressurising means may be secured non-removably to the can end member.

The dispensing container shown in Figure 1 comprises a steel can 10 having a cylindrical body shell 12; a bottom end member 14 secured by means of double seam 16 of the conventional kind over the lower open end of the body shell 12; and an upper end member 18 secured by a similar double seam 1 6 over the open top of the body shell. The can 10 is of the tin-plated steel, and its body shell 12 is of the kind having a welded longitudinal side seam, not shown. Each of the end members 14 and 1 8 is of a profile such that the can is capable of withstanding a continuous internal pressure of at least 70 psi (483 kN/m2), the construction of the shell 12 and seams 16 being determined accordingly.

A single through hole 20 is formed centrally in the top end member 18, and the can is charged with a liquid 22, either through this hole or through the open top of the can before the top end member 18 is affixed to the shell 12.

A pressurising means, in the form of a single, manually-operable, reciprocabie priming pump 24, is secured to the can 10 and sealably closes the through hole 20 as will be seen. The pump 24 is of the well-known kind, having externally of the can an actuating means in the form of a handle 26 connected to a plunger 28 (Figure 2) which applies pressure by forcing a gas (air) to flow into the can through an inlet duct 30, a simple nonreturn valve 32 of the diaphragm type being provided to retain this pressure. The inlet duct 30 has a safety valve 34 to limit the pressure within the can 10 to a permissible maximum value.

The container also has delivery means, comprising a spray-type dispensing head 36 having an on/off tap 38, a flexible tube 40 connecting the dispensing head 36 with a nipple 42, a dip tube 44 extending to the bottom of the can 10, and a duct 46 connecting the nipple 42 with the dip tube 44. The latter has a filter 48 at its lower end if required. Instead of the spray-type dispensing head 36, any desired type of applicator may be provided at the extremity of the flexible tube 40; other examples include a scrubbing or painting brush, or a paint roller or pad (with suitable control valve in each case), or a hollow lance for accurate placement of substances such as draught sealant, adhesive or woodworm killer.

The duct 46 is formed in the housing of the pump 24 so as to constitute flow passage means extending through the pressurising means and so that this part 46 of the delivery means extends through the single through hole 20 in the can end member 18.

Referring now also to Figures 2 to 5, it will be seen that, whereas in Figures 1 to 4 the pressurising means consists of the single pump unit 24 attached to the can, in Figure 5 no pump is shown. In the embodiment illustrated in Figure 5, the pressurising means comprises an adaptor unit 50 secured to the can and sealably closing the through hole 20. The adaptor unit 50 includes the inlet duct 30, delivery duct 46 and nipple 42 as before, but the outer end of the inlet duct 30 terminates in a pressure-containing non-return valve 52, which in the form shown is of the kind manufactured for automotive or bicycle tyres.The pressurising means in this example further comprises separate actuating means (indicated diagrammatically at 54 in Figure 5), which is in the form of any pump or compressor that is suitable for attachment to the valve 52, for example an automotive foot pump, a bicycle pump or a light electric compressor. The adaptor unit 50 may if desired have a safety valve such as the valve 34 shown in Figures 1 to 3.

In place of the inlet valve 52, there may be provided a closable valve of the kind suitable for admitting gas from a hollow bulb, cylinder or bottle when the valve is opened (either manually or by actuating automatically when a bulb containing liquefied gas is placed in position). The adaptor unit 50 may have suitable means, not shown, for holding such a bulb in engagement with such valve, or means, such as a screwthreaded boss around the outer end of the valve, for attaching a bulb holder in engagement with the valve.

Figures 2,3 and 5 also illustrate three ways in which the pressurising means 24 or 50 can be secured to the can 10, any of these ways being applicable either to a pump such as the pump 24 or to an adaptor unit such as the unit 50. In Figures 2 and 3 the pump 24 is secured removably to the can, whereby, when the pump is removed, the through hole 20 is exposed, so that the interior of the can 10 can be cleaned out if necessary so that it can be refilled when required.

In Figure 5, on the other hand, the adaptor unit 50 is shown permanently secured to the can end member 1 8.

Referring to Figure 2, the pump 24 is secured to the end member 1 8 by means of a female fitment 56 extending through the hole 20 and secured to the member 1 8 by means of a clinched seam 58 around the periphery of the hole 20. The fitment 56 depends into the interior of the can 10 from the seam 58 and has a screw thread 60 terminating in an optional, inwardly-directed bottom curl 62. The housing of the pump 24 has a screw threaded engaging that of the fitment 56, the curl 62 acting as a seat for the lower end face of the pump housing. An O-ring seal 64 is provided on top of the clinched seam 58 to seal the annular gap between the latter and a downwardly-facing annular shoulder of the pump housing.

Figure 3 shows a fitment 66, modified as compared with the fitment 50 by omission of the screw thread 60. The bottom curl, 68, of the fitment 66 is interrupted in one or more places as indicated at 70; whilst the lower end portion of the pump housing, which has no scew thread in this case, has a terminal flange 72 interrupted, as indicated at 74, in such a way that when the pump 24 is introduced to the can 10, the flange 72 passes through the interruption or interruptions 70, the pump then being secured by rotating it so that the flange 72 bears against the rear of the fitment bottom curl 68. In Figure 3, besides the seal 64, there is also shown a further O-ring seal 76, which may be provided instead of the seal 64.The O-ring 76 may also, if desired, be placed on the bottom curl 62 of the fitment shown in Figure 2 to bear against the bottom end face of the pump housing, in which case the seal 64 may be omitted.

In Figure 5, the lower end of the pump housing is upset to form a flange 78 which seals behind the bottom curl 68 of the fitment 66. The curl 68 is without the interruptions or recesses 70 seen in Figure 3. This flange is formed before the top end member 1 8 is secured to the can body shell 12, the fitment 66 having of course previously been secured to the member 18.

Referring now to Figure 4, this indicates at 80 the central portion of a domed can end member of a kind similar to that commonly employed on aerosol dispensing cans. The end member 80 has, around its central hole 20, a substantial curl 82 behind which the end portion of the pump housing is upset to form a sealing and securing flange 84 generally similar to the flange 78 seen in Figure 5.

Still by way of non-limiting example, the cans will typically be manufactured by securing the can end members to the body cylinder, the empty can being despatched to the filler with a temporary bung secured (by a screw thread, bayonet-type fitting etc. as appropriate) to the hollow fitment.

This bung is removed for the can to be charged with product, and it can then be replaced until it is removed by the user before the pressurizing means is attached.

Claims (15)

Claims

1. A dispensing container for flowable products, comprising: a steel can having a cylindrical body shell and an end member secured over each end of the shell, one of the end members having a through hole; pressurising means secured to the can and sealably closing the through hole, the pressurising means having actuating means external of the can for causing a gas to flow into the can so as to apply pressure to flowable conduct in the can; and delivery means terminating externally of the can for flow of the product therethrough from the can under the influence of such pressure.

2. A dispensing container according to Claim 1, wherein the pressurising means comprises a manually-operable priming pump.

3. A dispensing container according to Claim 1, wherein the pressurising means comprises an adaptor unit secured to the can and sealably closing the through hole, the adaptor unit having means for attachment thereto of separate actuating means such as, when so attached to be capable of causing said gas to flow through the adaptor unit into the can.

4. A dispensing container according to any one of the preceding Claims, wherein the said one end member has a single said through hole, the pressurising means and delivery means both extending through the through hole.

5. A dispensing container according to Claim 4, wherein the delivery means includes flow passage means extending through that part of the pressurising means which extends through the said hole.

6. A dispensing container according to any one of the preceding Claims, wherein the pressurising means is secured to the can entirely by attachment at or through the through hole.

7. A dispensing container according to any one of the preceding Claims, wherein the pressurising means is secured to the can at or through the through hole by means of a female fitment extending through the hole and secured to the can end member peripherally of the hole.

8. A dispensing container according to Claim 7, wherein the female fitment is clinched to the can end member peripherally of the fitment and of the hole.

9. A dispensing container according to Claim 7 or Claim 8, wherein the female fitment extends into the can.

10. A dispensing container according to any one of the preceding Claims, wherein, of the pressurising means and dispensing means, at least the former is secured removably to the can, whereby, upon being removed, to expose the through hole so that the can is refillable with flowable product.

11. A dispensing container according to Claim 10 when dependent on any one of Claims 7 to 9, wherein the female fitment has a screw thread, the pressurising means having a corresponding screw thread for co-operation therewith.

1 2. A dispensing container according to Claim 10 when dependent on any one of Claims 7 to 9, wherein the female fitment is provided with at least one radially inwardly extending projection for engagement with a corresponding recess of the pressurising means whereby the latter can be secured to the can by insertion into the fitment and rotation to lock the projection or projections into engagement with the pressurising means.

13. A dispensing container according to Claim 6, wherein the pressurising means has an axial projection extending through the through hole and upset behind the through hole to secure the pressurising means sealably thereto.

14. A dispensing container for flowable products, constructed, arranged and adapted to operate substantially as hereinbefore described with reference to, and as illustrated, in Figure 1 of the drawings hereof

1 5. A dispensing container for flowable products, constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated in, Figure 1 and any one of the Figures 2 to 4 of the drawings hereof.