Apparatus for dispensing a liquid from a liquid storage container

The apparatus includes a housing having a dispensing location for liquid disposed above a repository for a liquid storage container. A pressurising assembly including an air pump supplies gas to pressurize the container and cause liquid to leave the container via a delivery tube. A replaceable flow assembly including a manifold 30 and a reservoir 18 conveys liquid from the delivery tube 16 to the reservoir and thence from the reservoir 18 to the dispensing location. The manifold has an underside which includes a riser tube connector 36 and a reservoir connector 40 to rigidly mount the manifold on the reservoir. An upper side of the manifold has an outlet 33 located directly above the reservoir connector 40. The manifold contains a chamber 58 configured to convey liquid from the riser tube connector 36 to the reservoir 18 and a connector 37 for feeding a second reservoir provided with a steam venting valve. A valve connector 47 connects the steam venting valve to an air passage 29 which travels through a lifting handle 46 to the reservoir 18 via the chamber 58. The flow assembly contains no check valves or bypass valves and is self-purging on replacement.

TECHNICAL FIELD OF THE INVENTION

This invention relates to apparatus for dispensing a liquid such as water from a liquid storage container and a replacement flow assembly for use therein.

BACKGROUND

WO 2006 018 614 A1 discloses a replaceable flow assembly for use in a water cooler or similar bottled liquid dispenser. The flow assembly includes a liquid reservoir and a manifold incorporating a bottle connector for releasable sealing engagement with a neck formed on an inverted bottle. The manifold is mounted on the reservoir and incorporates a first pathway for conducting liquid from the bottle connector to the reservoir, and a second pathway for conducting liquid from the reservoir to a discharge outlet. A third pathway within the manifold conducts atmospheric air through an air filter and into the interior of the bottle through the delivery tube without passing through the reservoir. In a preferred embodiment the flow of liquid is assisted by an impeller which is incorporated in the manifold magnetically coupled to an external motor. Another embodiment is also described in which an external air pump pressurizes the bottle via the third pathway.

Bottled liquid dispensers also frequently include a hot tank which receives ambient water from the bottle and which incorporates a heating element to provide a supply of hot water at a separate discharge outlet. Water may leave the hot tank via a steam valve which automatically vents gases to prevent a dangerous pressure build-up.

In common with most contemporary water coolers, which are often referred to as “top loaders”, the bottle has to be inverted and lifted onto the top of the cooler. WO 2003 062 131 A1 discloses a water cooler in which the bottle does not need to be inverted and is placed in the bottom of the cooler—therefore known as a “bottom loader”. A liquid pump draws water from the bottle via a non-return valve. In one embodiment a passage with a flow restriction bypasses the non-return valve to prevent over-pressure in the system.

Replaceable flow assemblies as in WO 2006 018 614 A1 permit quick and easy sanitization of the water cooler by replacing the water contacting surfaces in a single operation. In bottom loaders however, the need to maintain adequate dispensing pressures makes it more difficult to provide a low cost and easily replaceable flow assembly. Furthermore, tortuous flow paths and complex valve arrangements can reduce flow rates and produce undesirable heat transfer to or from the various flow paths.

Various problems have been encountered with replaceable flow assemblies. Firstly, during replacement of the flow assembly there may be a tendency for water to spill out of the water inlet. A second problem is that in some circumstances the steam valve may permit the hot tank to siphon back into the bottle and empty. In bottom loaders a non-return valve and pressure relief valve may be included in the flow path from the bottle, but this adds to the cost of the assembly, and if the valves should fail back-siphoning can still occur. Another problem which has been encountered is that the cold reservoir does not always fill consistently. Ideally the unit will prime consistently and automatically when the flow assembly has been changed.

SUMMARY OF THE INVENTION

When viewed from one aspect the present invention proposes apparatus for dispensing a liquid from a liquid storage container associated with the apparatus, which includes:a housing having a dispensing location from which liquid from a liquid storage container is dispensed, and a repository to receive said liquid storage container;a first reservoir disposed in the housing, the first reservoir being configured to receive a liquid from the liquid storage container before the liquid is dispensed from the dispensing location;a second reservoir disposed in the housing, the second reservoir being configured to receive a liquid from the liquid storage container before the liquid is dispensed from the dispensing location, the second reservoir being provided with an automatic gas-venting valve;a delivery tube to convey liquid from said liquid storage container;a first transfer conduit to convey liquid from the first reservoir to the dispensing location;a second transfer conduit to convey liquid from the second reservoir to the dispensing location;
anda manifold operably connected to the delivery tube and the first and second reservoirs to convey liquid from said liquid storage container to both of said reservoirs, and operably connected to the first reservoir to convey liquid from the first reservoir towards said dispensing location via said first transfer conduit, said manifold having:an inlet to admit liquid from the delivery tube to the manifold,a first reservoir connector to rigidly mount the manifold on the first reservoir,a second reservoir connector to connect the manifold to the second reservoir,a valve connector for connection to the automatic gas-venting valve,a pathway to convey liquid from the inlet to the first reservoir via said first reservoir connector and to the second reservoir via said second reservoir connector,an outlet passage to convey liquid from the first reservoir towards the dispensing location via the first reservoir connector, andan air passage configured to admit air from the automatic gas-venting valve to the first reservoir via the valve connector.

In a preferred embodiment the manifold incorporates a lifting handle and the air passage travels along said lifting handle.

In a preferred embodiment of the dispensing apparatus the air passage incorporates an air flow restriction.

In a preferred form of dispensing apparatus the dispensing location is disposed above at least a portion of the repository and a pressurising assembly is disposed in the housing to supply a gas under pressure into said liquid storage container.

The pressurising assembly preferably includes an air pump and an over-pressure release valve.

The invention also provides a replacement flow assembly for use in the apparatus, which includes the manifold and the reservoir.

DETAILED DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention may be applied to various kinds of dispensing apparatus which require liquid to be withdrawn from a container. By way of example a preferred form of liquid dispensing apparatus will be described with reference toFIGS. 1 and 2.

Referring firstly toFIG. 1, apparatus for dispensing a liquid has an external housing1with a removable lid1a, and includes a dispensing location2in the form of a recess occupying a front portion of the housing, within which water can be dispensed into cups removed from a supply of cups3. In this embodiment the user has the option of dispensing chilled water or hot water by operating respective dispensing valves4and5. Beneath the dispensing location2a bottom portion of the housing is occupied by a repository6having a front access door through which may be loaded a liquid storage container in the form of a bottle.

Referring toFIG. 2, a bottle10containing water is loaded into the repository6with its neck uppermost. A releasable bottle connector11is sealingly engaged with the neck of the bottle, via which a pressurising assembly including an air pump12supplies air under pressure to pressurise the bottle. The bottle connector11may incorporate an air filter13. The outlet of the pump supplies the bottle via a non-return valve15to maintain pressurisation of the bottle and is provided with an over-pressure release valve14. The pump may be associated with a pressure sensor so that the pump only operates when necessary to maintain adequate pressurisation of the bottle. The over-pressure release valve14may vent air to atmosphere and limit any pressure rise within the bottle. The increased air pressure which the pump creates within the bottle enables ambient water to pass out of the bottle through a delivery tube16to a replaceable flow assembly17which incorporates a first reservoir18.

Water within the reservoir18may be chilled by means of a conventional cooling element20. When it is desired to dispense chilled water at the dispensing location2, operation of the cold valve5opens a first transfer conduit21through which water may flow from the reservoir18via a dip tube22which extends to the bottom of the reservoir.

Hot water may also be dispensed from a second reservoir in the form of a hot tank23which is provided with a suitable heating element24. The hot tank is filled with ambient water from the flow assembly17and supplies the hot tap4via an automatic gas-venting valve25and a second transfer conduit121. A preferred form of gas-venting valve has a chamber26through which passes hot water from the top of the hot tank23on its way to the hot tap4. The chamber26contains a float27which normally closes a gas vent28, but when steam, air or other gases are present in the chamber the float falls to allow the gases to escape through the vent.

In the illustrated flow assembly the top of the chamber26is connected by an air passage29to the top of the cold reservoir18. The air passage incorporates a flow restriction129, such as a small bore tube, the function of which is explained below.

It will be noted that no check valves or pressure relief valves are incorporated in the water flow path.

If required, ambient water from the flow assembly could also flow directly to an ambient water dispensing valve at the dispensing location2.

Referring toFIG. 3, which shows the dispensing apparatus with its lid1aremoved, the top of the cold reservoir18and the top of the hot tank23are both disposed at substantially the same level, flush with an internal partition wall8(also indicated inFIG. 2). The gas-venting valve25is mounted on top of the hot tank23above the partition wall8. The flow assembly17includes a manifold30and the cold reservoir18. Since the hot tank23and its connecting pipework are effectively sanitized by the temperature of the hot water it is not normally necessary to replace them as part of the flow assembly.

The replaceable flow assembly is shown removed from the dispensing apparatus inFIGS. 4 and 5. The manifold30may be formed from upper and lower components31and32. The upper component31provides the upper side of the manifold which has an outlet33for connection to the first transfer conduit21. The transfer conduit21may comprise a flexible length of tubing which is joined to the outlet connector33but at least part of the transfer conduit21could be integral with the manifold. The lower component32provides the underside of the manifold which includes an inlet36for connection to the delivery tube16. The underside of the manifold is also provided with a first reservoir connector40which is sealingly engaged with the neck of the reservoir18. The reservoir may be blow moulded of PET or a similar polymer, and is rigidly secured to the lower component32by the connector40. The reservoir connector40also includes an inner co-axial tubular portion44which connects with the dip tube22. The upper end of the tubular portion44extends upwards through the manifold to sealingly engage the outlet33of the upper component31. The manifold also has a second reservoir connector37, which is preferably a plug-in connector, to supply ambient water to the hot tank23.

The upper component31of the manifold30incorporates an inverted-U shaped handle46by which the flow assembly (manifold30and reservoir18) can be lifted in and out of the housing1. The manifold30contains a flow chamber58which provides a pathway to convey liquid from the inlet36to the reservoir18via the reservoir connector40and also convey liquid to the hot tank23via the second reservoir connector37. One end of the handle46is located adjacent to the reservoir connector40. The second end of the handle is located above the second reservoir connector37and incorporates a valve connector47which projects downward to sealably engage the top of the automatic gas-venting valve25. Air passage29travels through the handle and is configured to admit air from the automatic gas-venting valve25to the cold reservoir18via the valve connector47and the flow chamber58.

When either of the dispensing valves4or5is opened the pressurisation of the bottle10causes ambient water to flow through the delivery tube16into the flow chamber58. From the flow chamber ambient water can travel to the hot tank via the second reservoir connector37. When the cold dispensing valve5is opened, ambient water enters the reservoir18through the outer part of the reservoir connector40. Water entering the reservoir displaces chilled water from the bottom of the reservoir which flows up the dip tube22and through the straight inner portion44of the reservoir connector which passes transversely through the flow chamber58before entering the conduit21via outlet33. Since the period of thermal contact across the wall of the tubular portion44is only brief there is little thermal transfer between the ambient water and the chilled water.

When the flow assembly is replaced as part of a routine maintenance program the pump is turned off and the hot and cold taps4and5are opened allowing air to enter the steam-venting valve25through the vent port28. The taps4and5are held open so that the water level will continue to drop until it reaches the top of the hot and cold reservoirs18and23when the air break provided via the air passage29prevents the tanks from emptying. The restriction129in the air passage29slows down the entry of air into the flow chamber58and allows more water to drain back into the bottle10. This helps to ensure that the final water level in the flow chamber58is lower than the second reservoir connector37, and the manifold30and cold reservoir18can be lifted out of the dispenser without risk of spillage.

The delivery tube16may be replaced together with the manifold30and reservoir17along with the flexible tube21which leads to the cold dispensing valve5. The bottle connector11may also be replaceable, but the air pump12is not part of the replaceable flow assembly and will normally be a fixed part of the dispenser.

The incorporation of the air passage29improves the priming of the system after the new flow assembly has been installed. When the pump is started the cold reservoir will fill automatically with air being purged through the air passage29and vent28. The hot reservoir23will also fill until the water level reaches the steam-venting valve25causing it to close the vent28. The pump may be signaled to run for a period which is sufficient to fully purge the system, e.g. by depressing both taps simultaneously. When the system is fully purged of air the pressure relief valve14vents excess air until the pump shuts down.

In addition to self-priming and low risk of spillage the manifold which is part of the replaceable flow assembly has a small volume, a minimum number of components, allows free flow through all the necessary flow paths, and permits rapid dispensing of chilled liquid with minimum heat transfer between flow paths. The lack of check valves or pressure relief valves in the water flow path also means that the flow assembly is relatively inexpensive.

The flow assembly is designed to be a low cost disposable unit which can be changed at recommended service intervals, typically every 3 to 6 months. The configuration of the flow assembly, and the provision of a handle in a convenient position and orientation, means that it is very easy for the user to remove the flow assembly and re-insert a new one. The structure of the flow assembly also enables it to be manufactured from materials which do not impart any taste to the water.

Although the flow assembly has been described in relation to a bottom loader it could also have similar advantages when used with top-loading coolers without a pressurising pump. The apparatus may also be used for dispensing liquids other than plain water such as carbonated liquids, fruit juices etc. Instead of an air pump12the bottle may be pressurized by other means such as a CO2cylinder.

Whilst the above description places emphasis on the areas which are believed to be new and addresses specific problems which have been identified, it is intended that the features disclosed herein may be used in any combination which is capable of providing a new and useful advance in the art.