GB2576611A

GB2576611A - Dispensing Head and Dispenser

Info

Publication number: GB2576611A
Application number: GB1909320.2A
Authority: GB
Inventors: Geoffrey Worton Ian; Karl Neath Peter
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-08-24
Filing date: 2019-06-28
Publication date: 2020-02-26
Anticipated expiration: 2039-06-28
Also published as: GB201813828D0; GB2576611B; WO2020039156A1; GB201909320D0; GB201903615D0

Abstract

A dispensing head 11 for dispensing sauces and other flowable materials from a rigid container 13 having an outlet region (12 figure 1). The head comprises a body portion which defines a through bore and contact surface for seemingly engaging with the outlet region of the container. There is a closure member 18 for inhibiting the dispensing of flowable material from the container, the body portion having associated therewith or defining an airflow passage 20 which communicates between an air pump (16 figure 3) positioned, in use, externally of the container and an air flow outlet 20 from which air can be introduced via the body portion into the container by operation of the air pump.

Description

atmosphere = 29.92 in Hg ~ 14,7 psi ~ 101,325 Pa ~ 1,013.25 mb ™ 1.013 bar

Pressure

Dispensing Head And Dispenser

This invention relates to a method of and apparatus for dispensing non-solid material from a fixed volume container.

The invention relates in particular but not exclusively to a method of and apparatus for dispensing flowable material, such as sauces and other condiments, cosmetics, adhesives or pastes from a rigid container, such as a glass bottle.

Particularly in the case of sauces and other condiments it is known to utilise a container which is deformable whereby the container contents may be dispensed by careful squeezing the container to urge the contents to flow through a container outlet.

In some cases the container outlet is in the form of a nozzle which incorporates a simple valve member that deforms to allow dispensing of a required quantity of contents but then presents a seal to assist in containing the remaining contents within the container. In such constructions typically a cap component is provided for positioning over the valve after a required quantity of contents have been dispensed. In alternative constructions there is no valve member and a cap component is provided to fit over an outlet aperture, such as a non-deformable outlet aperture.

The use of a container which is deformable hitherto has been considered advantageous and preferable to a rigid, non-deformable container because it facilitates good control of flow of contents from the container. That flow generally can be successfully controlled by the degree to which the deformable container is squeezed. Thus there is avoided the problem associated with dispensing from a rigid container, such as a glass bottle containing ketchup or other such condiments, of the bottle needing to be shaken to urge the contents from the bottle. Control of the quantity being dispensed from a rigid container is not easily achieved.

However provision of a deformable container typically requires the use of a plastics material. Whilst that may be environmentally acceptable in the case of containers that are specifically intended for repeated use, in general the containers for may products such as sauces and other condiments are single use containers. It is now increasingly recognised that there is an attendant adverse environmental impact arising from the very large number of deformable plastic containers which have no significant re-cycling value or potential for re-cycling.

The present invention seeks to enable the functional benefits of ease of use of deformable plastic containers to be achieved without the need to form the containers from deformable plastics material and to avoid a requirement to decant material from an original container to another for the purpose of subsequently dispensing smaller quantities.

The present invention seeks to provide a method of and apparatus for addressing the aforementioned environmental issue.

In accordance with one aspect of the present invention a dispenser head for the dispensing of flowable material from a constant volume container having an outlet region comprises a body portion which defines a through bore for flow of flowable material therethrough from the container, a contact surface for sealingly engaging with the outlet region of the container and a closure member for resisting the flow of flowable material from the container, said body portion having associated therewith or defining an air flow passage which communicates between an air pump positioned, in use, externally of the container and an air flow outlet from which air can be introduced via the body portion into the container by operation of the air pump.

The body portion may comprise said air pump and said air pump may be an integral part of the body portion. Alternatively it may be separate. It may be supported by the body portion.

Typically it will be convenient to supply air into the container from the air pump via the outlet region of the container, typically the so-called mouth of the container. However if that container is provided with one or more other openings, one or more of those may be employed for directing air from the pump into the container.

The air pump may comprise an actuation surface that is movable to result in the pump supplying air through the airflow passage and into the container. The actuation surface may be substantially rigid and movable against the action of biasing means or it may be defined by a member of deflectable flexible material. Preferably the actuation surface inherently tends to return to an original, nondeflected position subsequent to being deflected to supply air through the air flow passage. Alternatively return to the original position may be assisted by repositioning means, such as a mechanical or elastomeric spring.

The air pump may be of a toroidal shape and may be positioned such that when the dispensing head is in contact with the outlet region of the container the toroidal air pump extends around, but not necessarily in contact with, that part of the container which is adjacent the container outlet region.

Preferably the air flow passage comprises a one way valve to prevent flow of air or flowable material in a reverse direction from the container to the air pump. The air flow outlet may comprise a supply tube which, in use of the dispensing head, extends into the container, for example in a direction towards that end of the container furthest from the container outlet region. A one way valve may be provided at the end of the supply tube furthest from the dispensing head body portion.

The air supply tube of a dispensing head intended for use with a specific size or range of sizes of container optionally may extend within the container to a position close to that end of the container furthest from the outlet region of the container.

The outlet end of the air passage defined by the tube preferably faces in a direction towards the outlet region of the container. Thus the air passage outlet is closer to the container outlet than the distal end of the tube.

The air supply tube may be substantially permanently secured to a part of the dispensing head or may be removable, for example for cleaning or for replacement by a tube of different length when the dispensing head is to be used with a container of a different size.

The outlet end of the air supply passage may comprise a one-way valve to prevent reverse flow from within the container towards the air pump. The outlet end may comprise a flap valve, which may be a valve of a type referred to as a bladder valve or pinch type valve, which expands when air is introduced under pressure into the container, but relaxes to reduce in internal volume when the airflow ceases. Alternatively or additionally at least part of the length of the air flow passage within a container may be of variable volume. In consequence of use of an air flow passage which is of variable volume, there is the advantage that subsequent to a required quantity of flowable material having been dispensed, any residual pressure in the container and potential tendency for further, continuing flow of material from the dispensing head is avoided or at least minimised.

The body portion may comprise a nozzle unit through which flowable material flows from the container towards the closure member, and beyond the closure member when that is in an open condition.

The nozzle unit may be integral with the body portion or may be a separate component that may be secured to and removed from the body portion. The airflow passage of the body portion may extend into the container via the nozzle unit.

The contact surface of the dispensing head for sealingly engaging with the outlet region of a container may be provided by the body portion or the nozzle unit. The contact surface may be that of a screw threaded formation which sealingly engages with a screw thread at the mouth region of the container and/or the contact surface may be a surface which is brought in to sealing contact with the container, for example with the substantially planar outlet end face of the container when the dispensing head is screw fitted or otherwise secured to the container.

The container may be secured to the dispenser head as a friction fit.

The dispensing head may comprise one or more barbs to engage with and, optionally, also to secure a container to the dispensing head. A barb may comprise an air flow passage for flow of air into a container. For use with a container which is supplied with a sealing member instead, for example, a screw or snap fitted closure, the barb(s) may be adapted to puncture the sealing membrane.

The body portion may comprise a closure member which is formed integrally with the body portion or is secured thereto. Alternatively the closure member may be releasably securable to the body portion.

The closure member may be in the form of a flexible membrane, such as a membrane comprising an outlet slit or aperture of other shape and which normally adopts a closed position to restrain flow of flowable material from the container but which deflects to allow flow from the container when air is introduced into the container by operation of the air pump.

Alternatively or additionally the dispensing head may comprise a closure member of substantially rigid form and which may be of a type which can be moved between a first position at which it prevents flow from the container to a second position at which it allows flowable material to be dispensed. The closure member may be a screw fit onto the body portion, a click fit or hinged, and may be resiliently biased normally to lie in at least one of a first and second position. The closure member may exhibit an over centre type action whereby it resides in either a first or second position in the absence of applied force.

A first valve member may be provided to prevent air entering the air pump chamber when the closure member is in the closed position. The first valve member may be of the type known as a shut off valve. A non return valve for the air pump may be provided in a passage or aperture through which air is able to enter the air pump. That passage or aperture may be aligned with the aperture or passage with which the first valve member is associated.

The dispensing head may comprise a support portion which extends away from the container-engaging contact surface of the body portion and allows an assembly of the dispensing head and container to be stood upright on a support surface with the container in an inverted position. The support portion may be an integral part of the body portion.

The support portion may be provided in combination with the body portion or in combination with the closure member in an arrangement in which the closure member is deflected from an open to a closed position when the assembly of a container and dispensing head is placed on a support surface with the container inverted.

The dispenser head may be part of a dispenser comprising said dispenser head and a protective enclosure member within which the container may be located. The body portion may provide support for or be integral with the protective enclosure member. Particularly for use with glass containers the enclosure may be adapted to protect the container from damage. The enclosure member may be of a flexible material, which may be a resilient material, or may be rigid. Optionally an internal surface of a rigid enclosure member may be provided with cushioning material. An enclosure member may wholly or only partly surround the container.

An end region of the enclosure member furthest from the container mouth may be in the form of a cap. Said cap may be of a non-planar shape, for example of a domed shape, or comprise upstanding tabs, whereby it prevents the assembly of the dispensing head and container being stood with the container outlet region uppermost. Alternatively the cap may be independent of any enclosure member. Thus it may be employed in combination with a dispenser head and without use of an enclosure member.

The enclosure member may comprise viewing apertures or be transparent at least in part whereby the level of contents in the container may be viewed.

The invention provides also a method of dispensing flowable material from a container of the constant volume type wherein a dispenser head is employed to engage with the mouth of the container and enable air to be admitted to within the container through the mouth of the container.

Admitted air may be provided by a hand operated pump. The pump may be integral with or supported by the dispensing head or dispenser, or may be remotely positioned. Alternatively the air pump may be battery powered.

The nozzle unit may have an outlet shaped to dispense material in a strip-like form which may, for example, be of a circular, rectangular or wave-like cross section. The nozzle unit may be adapted to dispense material as a spray. The nozzle may comprise a plurality of outlets whereby a plurality of streams of material may be dispensed concurrently.

The dispensing head may have associated therewith a component which provides a visual indication that the air pump is operating correctly, for example a flag or deformable member which is externally visible in use ofthe dispensing head and which moves in response to an increase of air pressure.

Operation of the air pump may be arranged to provide an audible indication that the air pump is operating correctly. An audible indication may be provided by, for example a whistle or vibration of a reed. The audible signal may be created when pressure in a container attached to the dispensing head is increased by operation of the air pump and/or when that pressure reduces. The audible indication may be a musical tune.

The dispensing head may incorporate a light unit and the light unit may be arranged to illuminate when the air pump is operated. The light unit may be powered by a small solar panel, a battery, or in consequence of a device which generates power in response to movement of a component of the air pump or change of air pressure.

In a preferred embodiment the invention provides a dispenser assembly comprising a dispensing head having a body portion for sealingly engaging with the mouth of a container, an air pump, and a closure member provided in combination with an enclosure which in use surrounds the container and serves to prevent the container being stood upright with the outlet region uppermost, the body portion comprising an air passage whereby air may flow from the air pump through the dispensing head and through the outlet region of the container. The air pump may be supported by or integral with the enclosure and/or the dispenser head body portion.

Although the invention is directed particularly to a dispensing head for use with rigid containers that contain sauces and other such condiments for which deformable plastic containers are manufactured in very large quantities, the present invention may be employed also for the dispensing from rigid containers of flowable materials such as adhesives and for which the volume production of containers is less than that for sauces and other condiments.

The dispensing head may be employed to inflate an inflatable body or apply pressure to a component, such as a piston, positioned within a container and which thereby causes flowable material to be dispensed from the container.

Although the present invention is particularly suitable for the dispensing of sauces and other such condiments which may be regarded as being of a paste-like form, it may be employed also for the dispensing of other, relatively fluid type condiments such as vinegar and oils.

Various features of the present invention including those aforedeschbed and additional features will now be described in respect of embodiments directed to a socalled sauce pump suitable for use with non deformable bottles such as bottles of glass or rigid plastics material.

An important objective of the dispensing head of this invention is to provide users with the functional advantage of squeezable plastic bottles for dispensing sauces or other flowable products in combination with the environmental benefit of purchasing glass bottles.

Embodiments of the present invention are now described with reference to the accompanying diagrammatic drawings in which:Figure 1 is a perspective view of a dispenser assembly in accordance with the present invention:

Figure 2 is a longitudinal sectional view of the assembly of Figure 1;

Figure 3 is a cross-sectional view of the dispenser head of the assembly of Figure 1, with the closure member in an open position;

Figure 4 is a perspective view, part cutaway, of the dispenser head of Figure 3 in combination with the outlet mouth end of a container, with the closure member in a closed position;

Figure 5 is a perspective of the body portion of the dispenser head;

Figure 6 is a cross-sectional view of the body portion of Figure 5;

Figure 7 is a perspective view, part cutaway, of the pump unit;

Figure 8 is a perspective view of the nozzle unit of the dispenser head;

Figure 9 is a perspective view, part cutaway, of the nozzle unit of Figure 8;

Figure 10 is a cross-sectional view of the distal end region of the air inlet tube;

Figure 11 is a perspective view of the air outlet valve of the inlet tube;

Figure 12 is a perspective view in a first direction, part cutaway, of the outlet valve of Figure 11;

Figure 13 is a perspective view in a second direction, part cutaway, of the outlet valve of Figure 11;

Figure 14 is a perspective view, part cut away, of a dispensing head provided with an alternative outlet valve;

Figure 15 is a perspective view of the protective enclosure of the assembly of Figure 1, and

Figure 16 is a graph showing the relationship between air pressure within a container and the volume flow of air, annotated to show the successive operating conditions of the dispenser head.

A dispenser assembly 10 (see Figures 1 and 2) comprises a dispenser head 11 secured to the mouth region 12 of a container 13 of flowable material, such as a sauce or condiment, and a protective enclosure sleeve 14.

The dispenser head 11 (see Figure 3-7) comprises a body portion 15, a hand operated air pump 16 supported by the body portion, a nozzle unit 17 and an enclosure member 18 which is pivotally secured to the body portion 15. The nozzle unit provides location for an air supply tube 20 that receives air from the pump 16 via passages 21,22 in the body portion and the nozzle unit respectively.

The body portion 15 (see Figure 5 and 6) comprises a frusto conical section 25 the larger diameter end of which pivotally supports the closure member 18. That end also defines surface regions 26 for standing the dispenser head on a support surface in combination with an inverted container.

A substantially shaped cylindrically shaped locator section 27 extends from the smaller diameter end of the frusto conical section 25 and defines a radially inner surface 28 adapted for frictionally engaging with the outer surface of the mouth region of the container 13. However in an alternative construction it may comprise a screw thread to engage with a screw thread at the mouth region of the container.

The inner surface 28 also locates the nozzle unit 17 which rests on a radially inwardly extending flange 29 of the body portion.

The body portion also defines said air passage 21 which extends in a radial direction of the body portion for flow of air from the air pump to the nozzle unit.

The larger diameter end of the frusto conical section 25 defines a cut out region 31 in which the distal end 34 of the closure member 18 is located when the closure member is in the closed position as shown in Figure 4. Said larger diameter end also defines a cut out region aligned with the region 31 to provide for finger access to deflect the closure member to the open position of Figure 5. Retention of the closure member in the closed position is assisted by inter-engagement of the click fit projections 36, 37 provided respectfully by the body portion and closure member.

The closure member 18 is provided with a projection 35 which in use sealingly engages with an outlet aperture 40 of the nozzle unit when the closure is in the closed portion of Figure 4.

The outer surface of the body portion 15 supports the air pump 16 which is held in position as a friction fit around the body portion. The pump is of a toroidal shape to extend fully around the body portion and an inner cylindrical surface region 42 is a tight fit around the surface of the body portion locator section 27.

The air pump is formed as an integral moulding of plastics material, such as silicone rubber.

The outer surface region 41 of the air pump is relatively flexible whereby pressure applied to the pump causes a reduction in volume of the air chamber 43 within the pump. In contrast, a lower region 44 of the air pump is relatively thick whereby it is substantially inflexible and, in the assembly of the dispenser head, is located around the frusto conical section 25 of the body portion 15.

The air pump is provided with two air flow apertures (see Figure 7). One aperture 45 sealingly extends around a tubular projection 46 of the body portion and which defines the air passage 21 for flow of pressurised air from the chamber 43 to the air supply tube 20.

The other aperture 47 allows air to enter the chamber 43 as the outer region 41 of the pump relaxes from a deformed condition to the original, non-deformed condition.

Entry of air into the chamber 43 through the passage 47 is via a non-return valve 49c located at a position 49a where the passage 47 enters the chamber 43 thereby to prevent escape of pressurised air from the chamber 43. The other end of the passage 47 is aligned with an opening 49b in the body portion and a flap valve 48 extends over that opening. The flap valve 48 is pressed against the opening 49b by the closure member when the closure member is in the closed position thereby to prevent flow of air into the air pump when the nozzle outlet 40 is closed. When the closure member is in the open position the valve inherently lies away from the opening 49b thereby to allow air to flow into the chamber.

The nozzle unit 17 (see Figures 8 and 9) is a moulding of medium strength silicone rubber and is held in position within the cylindrical locator section 27 of the body portion by means of a circumferentially extending groove 50 which, in the assembled dispenser head, locates with inwardly directed protrusions 51 of the locator section

27.

The nozzle unit also comprises a circumferentially extending air supply groove 52 which aligns with the body portion air passage 21 irrespective of the relative rotational orientation of the nozzle and body portion. Within the nozzle unit the aforementioned air passage 22 of the nozzle unit extends from the air supply groove 52 towards an end face 53 of the nozzle at a position 54 which is adapted to receive an end of the air supply tube 20.

The nozzle additionally defines an outlet passage 55 that, in use, allows flowable material to flow from the container to the nozzle outlet 40.

The nozzle end face 53 serves as a contact surface for sealingly engaging with the mouth of a container when the end of a container is positioned within and supported by the inner surface 28 of the body portion irrespective of whether the container is a friction fit or is screwed into position..

The distal end region 60 of the air supply tube 20 (see Figures 10 to 13) may comprise a bend region such as that of a II shape whereby the outlet faces in a direction towards the nozzle unit 17. However in this embodiment of the invention the distal end 60 is provided with a valve unit 61 of moulded silicone rubber. The valve unit 61 comprises an inlet port 62 which is a close fit over the end of the tube 20 and an outlet port 63 from which, in use, pressurised air may enter the container. The outlet port 63 is located alongside the inlet port 62 and faces in a direction towards the nozzle unit 17.

Optionally the valve unit 61 may comprise a non-return valve but in this embodiment the valve unit is provided instead with a variable volume air chamber 64 defined primarily by the space between two thin, flexible wall sections 65 of low shore rubber. In use the wall sections deflect to increase the volume of the chamber 64 when air is received from the tube but relax to the condition as shown in Figure 13 when the flow of air from the tube 20 and flow of material from the container ceases. That has an advantageous effect, namely, as also reflected in Figure 16, the chamber 64 expands when air is pumped in from the air pump but when the air supply ceases the pressure in the chamber balances with that in the container, thereby creating a sudden reduction of pressure such that material is no longer urged to flow from the container.

Figure 14 shows a dispensing head 80 provided with an air passage pipe 81 having a distal end 82 of a II shaped form. Part 83 of the length of the pipe 81 is expandable in cross section when the air pump is operated, and relaxes to reduce in cross section and thus volume when the air pump ceases operation. In consequence the air pressure within the container is reduced thereby to minimise any tendency for flowable material to continue to flow from the container through the dispensing head.

The protective enclosure sleeve 14 is shown in more detail in Figure 15. The sleeve is positioned to extend in the assembly of the dispenser head and container over part of the container but to be spaced from the mouth region of the container and air pump as shown in Figure 1.

The enclosure sleeve is formed from a semi-rigid plastics material and comprises a pair of outwardly extending end flanges 70 and longitudinally extending internal ribs 71 whereby in use the flanges and ribs cushion forces on the container, such as might damage a glass container, when dropped. One end, an upper end 72 of the protective sleeve comprises a pair of upwardly extending tabs 73 which prevent the assembly of the container and dispensing head being stood inverted on a support surface with the dispensing head uppermost.

The upper end 72 additionally is formed with four inwardly extending tabs 74 which bear against the end of the container. Thus the protective sleeve is prevented from sliding downwards toward the air, and remains in position to protect the end of the container furthermost from the air pump.

Having regard to the foregoing it will be appreciated that the present invention provides a dispensing head that enables users to enjoy the functional advantage of squeezable plastic bottles for dispensing flowable products, such as sauces and other condiments, along with the environmental benefits of purchasing the required product in a glass rather than a plastic bottle. A further advantageous feature is that versions of the invention allow product to be dispensed in a more controlled manner than when conventionally dispensing from rigid containers.

Claims

1. A dispensing head for the dispensing of flowable material from a constant volume container having an outlet region comprises a body portion which defines a through bore and contact surface for sealingly engaging with the outlet region of the container and a closure member for inhibiting the dispensing of flowable material from the container, said body portion having associated therewith or defining an airflow passage which communicates between an air pump positioned, in use, externally of the container and an air flow outlet from which air can be introduced via the body portion into the container by operation of the air pump.

2. A dispensing head according to claim 1 wherein the airflow passage comprises a one way valve to prevent flow of flowable material in a reverse direction from the container to the air pump.

3. A dispensing head according to claim 1 or claim 2 wherein the air flow outlet comprises a supply tube which, in use of the dispensing head, extends to within the enclosure.

4. A dispensing head according to claim 3 wherein the supply tube extends in a direction towards that end of the container furthest from the container outlet region.

5. A dispensing head according to claim 3 or claim 4 wherein a one way valve is provided within the supply tube.

6. A dispensing head according to any one of the preceding claims wherein the body portion comprises a closure member.

7. A dispensing head according to claim 6 wherein the closure member comprises a flexible member which inherently tends to adopt a closed position to restrain flow of flowable material from the container but which deflects to allow flow of flowable material from the container when air is introduced into the container by operation of the air pump.

8. A dispensing head according to any one of the preceding claims wherein the closure member comprises a rigid component movable between a first position at which it prevents flow from the container to a second position which allows flowable material to be dispensed.

9. A dispensing head according to claim 8 wherein the closure member is operable with an over-centre type action whereby it inherently tends to reside in either a first or a second position in the absence of applied force.

10. A dispensing head according to claim 8 or claim 9 wherein the air pump comprises an air inlet provided with a valve which is adapted to prevent air entering the air pump when the closure member is in said first position.

11. A dispensing head according to any one of the preceding claims wherein the body portion comprises a support portion which extends in a direction away from the container engaging contact surface thereby to allow an assembly of the dispensing head and a container to be stood upright on a support surface with a container in an inverted position.

12. A dispensing head according to claim 11 when dependant on claim 8 or claim 9 wherein the support portion is provided in combination with the closure member in a configuration in which the closure member is deflected from an open to a closed position when the assembly of a container and dispensing head is placed on a support surface.

13. A dispensing head according to any one of the preceding claims wherein the body portion provides support for an enclosure within which a container may be located for sealingly engaging with said contact surface of the body portion.

14. A dispensing head according to claim 13 wherein the enclosure is adapted to protect the container from damage.

15. A dispensing head according to claim 12 or claim 13 wherein the enclosure member comprises an end region furthest from the contact surface of the body portion, said end region being shaped to prevent an assembly of a dispensing head and a container being stood with the container outlet region uppermost.

16. A dispensing head according to any one of claims 13 to 15 wherein the enclosure comprises a viewing aperture or at least in part is of transparent material whereby the level of contents of the container may be viewed.

17. A dispensing head according to any one of the preceding claims wherein the air pump is integral with or supported by the dispensing head.

18. A dispensing head according to any one of the preceding claims wherein the air pump is of an annular shape.

19. A dispensing head according to any one of the preceding claims wherein the air pump extends around a support portion of the dispensing head body portion.

20. A dispensing head according to any one of the preceding claims wherein the air pump comprises a deformable bladder.

21. A dispensing head according to any one of the preceding claims wherein the airflow passage comprises a supply tube which is selectively removable from sealing engagement with the air pump for cleaning and which is replaceable for sealing engagement with the air pump.

22. A dispensing head according to any one of the preceding claims wherein the air flow passage comprises a supply tube having a distal end of II shape.

23. A dispenser assembly comprising a container and a dispensing head according to any one of the preceding claims wherein an outlet region of the container sealingly engages with said contact surface of the dispensing head body portion.

24. An assembly according to claim 23 wherein the air flow outlet comprises a supply tube which extends into the container and wherein the end of the supply tube is in proximity with that end of the container furthest from the container outlet region.

25. An assembly according to claim 23 wherein the air flow outlet comprises a supply tube which extends into the container and wherein the end of the supply tube is at a position sufficiently remote from the container outlet region thereby to minimise or avoid the risk of air cavitation and an associated unwanted direct flow of air from the supply tube to said outlet region underneath a head of flowable material.

26. An assembly according to any one of claims 23 to 25 wherein the container is a rigid container.

26. An assembly according to any one of claim 23 to 25 wherein the container, when in engagement with the dispensing head, is substantially devoid of non-recyclable plastics material.

27. A method of dispensing flowable material from a container of the constant volume type comprising providing a dispenser head to engage with the mouth of the container and enable air to be emitted to within the container through the mouth of the container.

28. A method according to claim 27 and comprising use of a dispenser head according to any one of claims 1 to 22.