BACKGROUND ART Combined pumps and dispensing valves are well known for use in connection with flexible high barrier bags, semi-rigid and rigid containers.

These types of containers are often contained within wallmounted or free standing dispensers. Flexible bags with these types of combined pumps and dispensing valves are used to contain and dispense liquid hair and skin care products, antiseptic medical products, food products and industrial liquids.

Prior art designs are known to incorporate metal parts such as metal springs or metal balls in their ball valves. These types of prior art combined pump and dispensing valves are also known to leak and perform inconsistently.

SUMMARY OF THE INVENTION According to one aspect of the invention there is provided a combined fluid pump and dispensing valve comprising:- (i) a backing plate having an inlet adapted to be connected to a supply of fluid, (ii) an outer flexible housing sealed against the backing plate, the outer housing having a dispensing orifice, (iii) an inner flexible housing captured between the backing plate and the outer housing, the inner flexible housing having at least one passageway allowing fluid flow from within the inner housing towards the dispensing orifice, (iv) a closure member adapted to close the dispensing orifice when the outer housing an the inner housing are in a non-dispensing

disposition and to open the dispensing orifice when the outer housing and the inner housing are pressed towards the backing plate in a dispensing disposition, and (v) a valve adapted to close the inlet when the outer housing and inner housing are pressed towards the backing plate.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side elevation of a combined pump and dispensing valve according to one embodiment of the present invention; Fig. 2 is a cross section of an alternative backing plate for use with the pump and valve arrangement of Fig. 1, Fig. 3 is a cross sectional view of the device depicted in Fig. 1, when relaxed; Fig. 4 is a cross sectional view of the device depicted in Fig. 3 when compressed for dispensing; Fig. 5 is a top plan view of an inner dome with an integral sealing flap ; Fig. 6 is a side elevation of the inner dome depicted in Fig. 3 illustrating how the flap is folded prior to assembly; Fig. 7 is a plan view of a separate sealing membrane; and Fig. 8 is an exploded perspective view of a combined pump and dispensing valve according to another embodiment of the present invention incorporating a separate membrane of the type depicted in Fig. 7.

As shown in Fig. 1, a combined pump and dispensing valve 10 according to one embodiment of the invention includes a backing plate or backing plate assembly 11 in which is formed an inlet opening 12. The inlet

opening 12 can pass through a nipple, bayonet or spigot 13 which permits the device 10 to be coupled to a bag or a container or a tube containing the fluid which will be dispensed. The backing plate 11 fluidically couples with a flexible outer dome 14 which provides the pumping action required to dispense the liquid.

As shown in Fig. 2, other forms of backing plates or backing plate assemblies may be used in conjunction with the other components which will be described. In essence, the backing plate serves as a means for holding an outer housing in the form of a semi-spherical dome 14 and the internal components required for the operation of the device 10 and providing a convenient inlet. The particular style of backing plate 11 depicted in Figure 2 is ideally suited for bag-in-box containers. As such, the outer surface of the backing plate 11 incorporates circumferential ribs 15 which define a peripheral groove 16 which is adapted to engage the outer cardboard box of a bag-in-box type container.

As shown in Fig. 3, a backing plate assembly 11 may be provided in two distinct pieces. In this example, the backing plate 11 comprises a disc-like backing element 30 and a locking ring 31. The locking ring 31 holds the flexible outer dome 14 in sealing engagement with the backing disc 30. The flexible outer dome 14 is shown as further comprising an integral dispensing nozzle 32 which comprises an inner bore 33 and integral diaphragm 34 and a dispensing outlet 35.

An inner housing which in this instance is in the form of a semi-spherical dome 40 occupies the space between the outer dome 14 and the backing plate 11. The inner dome 40 acts as a resilient spring so as to urge the outer dome 14 into its initial or relaxed position after it has been depressed to dispense fluid from the space between the backing plate 11 and the inner dome 40 (see

Fig. 4). The inner dome 40 incorporates (for example) four large through passageways 41 which allow the liquid passing through the inlet 12 to reach the outlet orifice 35. The lower portion of the inner dome 40 is characterised by guide fins 42 whose tips are guided and retained by the inner bore 33 so as to maintain the correct orientation between inner dome 40 and outer dome 14. In this instance, the inner dome 40 terminates in a closure member or spear 43 which is preferably tapered.

When the interior space of the outer dome 14 is pressurised during dispensing, the diaphragm 34 flexes away from the interior as suggested by the arrow 44 in Fig. 3. This creates an opening between the dispensing outlet 35 and the spear 43 as shown in Fig. 4. Accordingly, the diaphragm 34 is preferably formed in the shape of an inverted dome (relative to the outer and inner domes) having a central tapered spout 45 which terminates at its lower end with the dispensing outlet orifice 35. When the internal pressure is relieved the diaphragm 34 reverts to its initial position and seals against the spear 43 as shown in Fig. 3.

Fig. 5 illustrates the construction of a preferred embodiment of the inner dome 40. The inner dome 40 comprises a reinforced outer rim 50 with integral ribs 51 separated by through openings 41. The inner dome 40 may also include an integral flap 52.

As shown in Fig. 5, the flap 52 is manufactured in the same plane as the rim 50 but outside of, or away from, the interior of the rim 50. In this way, and as shown in Fig. 6, the flap 52 may be folded inwardly or centrally of the rim 50.

As shown in Figs. 3 and 4, the flap 52 then occupies the space just below the inlet 12 and acts as a one way or reed valve.

When the pressure internal to the outer dome 14 is greater than the pressure in the inlet 12, the flap 52 seals against the inlet 12 and prevents

back flow into the container which supplies the fluid to be dispensed thus increasing the efficiency and predictably of the amount of fluid dispensed through the outlet orifice 35.

When the pressure in the inlet 12 is greater than the pressure interior to the inner dome 40, the flap 52 flexes inwardly so that the inner dome 40 can fill with fluid. As suggested in Fig. 6, the folding 54 of the flap 52 results in a natural tendency of the flap, once assembled, to exert an upward bias 55. This increases the sealing efficiency of the flap 52 against the inlet 12.

As shown in Figs. 7 and 8, the device 10 may be provided with a one way valve without the necessity of an integral flap 52. In this embodiment, a separate sealing membrane 60 is provided between the inner dome 40 and the backing disc 30 or backing plate. The membrane 60 includes through openings 61 which allow fluids to pass through the membrane 60. The membrane flexes or moves according to the pressure differential across it and thus seals against the inlet opening 12 when the interior pressure is greater than the feed pressure during a dispensing operation. When the internal pressure is lower than the feed pressure, the membrane 60 flexes and allows fluid to fill the interior of the outer dome 14.

It is preferred that the interior dome be fabricated from a polymer with a high degree of shape memory and resiliency. This is because the speed at which the outer dome 14 fills with fluid from the inlet 12 is largely determined by the expansive forces exerted by the inner dome 40. Flexibility, resiliency and shape memory are also properties desirable in the outer dome 14, particularly as the diaphragm 34 must return to its initial position after dispensing. Accordingly, the entire device 10 may be formed from polymers without the need for metal springs or balls.