The invention relates to a portable beverage dispenser, for use at events. It is known to provide beverage vendors with a frame with a tank with beverage, for instance soft drinks or beer, thereon. With the frame, the tank is carried on the back and a tap installation is coupled to the tank, with which the vendor can pour the beverage into cups. Here, use is made of an exchangeable tank with beverage. When the tank is (almost) empty, the vendor goes to a distribution point where the tank is replaced by a full tank. Such a beverage dispenser has the drawback that it requires a special type of tank. For economic reasons, a special tank is necessary which needs to be able to contain considerably more liquid than a standard beverage bottle and, moreover, the tank needs to have been made specially suitable for tapping via a faucet, for instance with the aid of a pressure installation. During use of such an unusual tank for ambulatory trade it is, moreover, necessary to provide extra brand indications to communicate the quality of the beverage to the users.

It is one of the objects of the invention to provide a portable beverage dispenser in which use can be made of a plurality of beverage bottles, preferably standard, conventional beverage bottles intended for the consumer, such as PET bottles. It is a further object of the invention to enable pouring out from a plurality of bottles in such a portable beverage dispenser without switching between the bottles being necessary. It is a further object of the invention to provide a method for ambulatory distribution of beverage where a plurality of standard bottles are used in a simple manner. A portable beverage dispenser according to the invention is claimed in claim 1. According to the invention, a frame is provided with a supporting plate with connections for a plurality of bottles. The supporting plate is carried on the back, with the connections directed upwards, so that the bottles can be carried on the supporting plate upside down. The plurality of bottles are connected with a joint faucet and a gas supply ensures that sufficient pressure remains in the bottoms of the bottles turned upwards to continue pouring. In use, the frame is "loaded" by turning it around, so that the connections are turned downwards, and the bottles are mounted to the connections in that position, for instance with a thread as is normally used for the cap of the bottle. After mounting the bottles, the frame is turned, so that the bottles are upside down and the whole is hanged on the back of the vendor (or more generally the "pouring person"). In a first embodiment, the gas supply is realized with a gas cartridge and a control valve. In this embodiment, the supporting plate contains a connecting space closed towards the outside through which the beverage flows from the connecting openings to the faucet. The gas cartridge is connected to the connecting space via the control valve to maintain a predetermined pressure in the connecting space. The gas let in flows to the bottles, so that, in each of the bottles, the same pressures prevails above the beverage, corrected for the hydrostatic pressure of the liquid column in the respective bottle. In a second embodiment, the connections for the bottles are provided with gas pipes which project outwards from the connection, so that, in the mounted bottles, the gas pipes reach to virtually the bottom of the bottles. The gas pipes may, for instance, be connected to the faucet, so that, each time during tapping, air is let into the upward facing bottoms of the bottles. Alternatively, the gas pipes may permanently be connected with a vent opening which reaches above the bottles in use, or use can be made of a gas cartridge.

These and other objects and advantages of the invention will be 5 described in more detail with reference to the following drawings, in which: Fig. 1 shows a beverage dispenser; Fig. 2 shows a top plan view of a suppor-ting plate; Fig. 3 shows a side elevational view of a_ supporting plate; and Fig. 4 shows a side elevational view of a_n alternative embodiment. 0 Fig. 1 shows a beverage dispenser with a frame comprising a supporting plate 10, a back support 14 and a s upporting strap 15. The frame is carried on the back by a beverage vendor 1. Supporting plate 10 contains connections 20 for bottles 12. To supporting plate 10, a pouring tube 16 is 5 connected which terminates in a faucet 18. Fig. 2 shows a top plan view of supporti-ng plate 10, with connections 20 for bottles 12 therein. Bottles 1 2 are, for instance, standard 1.5-liter PET bottles with a thread for a closing cap on the mouth. (The standard for this is, for instance, laid down in "the 28 BPF standard of the 0 British Plastics Federation.) In this case, connections 20 are, for instance, provided with a complementary thread, with which the bottles 12 are screwed on supporting plate 10. Although, by way of example, the Figure shows six connections 20 in a virtual circular arrangement, it will be clear that different numbers of connections 20 and arrangements are possible as 5 well (for instance in a grid). Fig. 3 shows a side elevational view of supporting plate 10, with a control valve 32 and a gas cartridge 30 thereon. In the embodiment shown, supporting plate 10 encloses a hollow space in which both connections 20 and control valve 32 terminate and to which tuibe 16 (not shown) is o connected as well. Back support 14 contains, for instance, a construction with a rod which, during carrying, first runs down along the carrier's back, then forms a loop in a plane virtually perpendicular to the back, and then runs up again along the carrier's back. In this case, the loop is designed such that the rod falls into a slot in the outer perimeter of supporting plate 10 or that supporting plate 10 is suitable to be clamped to the rod. The ends of the rod preferably continue over the carrier's shoulder. In use, the apparatus is first "loaded" by connecting a plurality of bottles 12 thereto. For this purpose, supporting plate 10 is turned around, if necessary together with the rest of the frame, so that connections 20 terminate downwards. In this position, bottles 12, their caps removed, are screwed on the respective connections 20. When bottles have been screwed on all connections (or closing means have been screwed on any non-used connections), supporting plate 10 is turned around again and taken on the back by vendor 1 as part of the frame. Optionally, supporting strap 15, which is fixed to back support 14 and/or, via one or more columns (not shown), to supporting plate 10, keeps the bottles 12 in place. Before use, control valve 32 is opened. In this condition, vendor 1 pours out beverage via tube 16 and faucet 18. The frame is preferably provided with straps (not shown) which run over the breast of vendor 1 and to which a holder for cups is provided. In that case, vendor 1 each time takes a cup from the holder, holds the cup under faucet 18 and pours out beverage. Control valve 32 controls the pressure in the hollow space of supporting plate 10 by letting gas (preferably CO2 gas) from gas cartridge 30 into the hollow space if the pressure in this hollow space drops below a threshold value. As a threshold value, for instance some tenths or a half atmosphere of overpressure may be taken. The gas spreads over the upper side of the hollow space and flows therethrough to bottles 12 (or, if connections 20 have a rim which projects into the hollow space, the gas flows to the bottles as soon as there is sufficient gas in the hollow space to force out the liquid to below the projections). Thus, the gas pressure above the beverage in the bottles 12 (i.e. in the bottoms of the bottles facing upwards) will become equal to the gas pressure in the supporting plate 10, as determined by control valve 32, minus the hydrostatic pressure of the liquid columns in the respective bottles 12. When the beverage is poured out, the pressure decreases, after which control valve 32 comes into operation to restore the pressure. Depending on the distribution of the gas, the gas will thereby flow to one or more bottles. Thus, during tapping, the liquid level drops in one or more of the bottles 12. In the extreme case that all the added gas initially flows to one bottle, the gas will eventually flow to the other bottles when this bottle is empty, until all bottles are empty. Preferably, slots are provided in supporting plate 10, in the inner surface of the wall of supporting plate 10 which forms the upper wall during carrying, while the slots run from the mouth of control valve 32 to the connections for the bottles. Hereby, the gas is guided directly to the bottles, thus reducing the risk of formation of a bubble in a corner of supporting plate 10. Although control valve 32 and gas cartridge 30 are shown to be mounted directly on supporting plate 10, it will be clear that they can also be mounted elsewhere, either individually or both, with a gas connection to the supporting plate. In one embodiment, for instance, a closable cock is provided between gas cartridge 30 and the space inside supporting plate 10 and gas cartridge 30 and the closable cock are mounted on the frame within the carrier's reach, so that the carrier can increase the gas pressure above the liquid or not, as desired. This saves gas. This is because, in most cases, the carbon dioxide dissolved in the beverage generates sufficient pressure, so that a supply of gas from gas cartridge 30 is unnecessary. By also mounting the gas cartridge on the frame, it can be replaced quickly, if necessary during carrying. Instead of a gas cartridge, a hand pump may also be used to increase the gas pressure in the hollow space of supporting plate 10. Instead of gas cartridge 30 and control valve 32, other means may also be used to supply gas to the bottoms of bottles 12.

Bottles 12 may also be provided with a flange near the mouths (as is the case with standard PET bottles). In that case, instead of or in addition to a thread, use can be made of a clamp closure (according to the principle of the closure of swing-top bottles such as Grolsch bottles). The clamp closure comprises an engaging part which engages behind the flange and thus forces the bottles with the flange towards supporting plate 10. The engaging part is coupled to a lever which is mounted so hingedly that the lever can be pulled, via a metastable position, from a free position to a clamping position where the lever abuts the supporting plate 10. Here, the lever is mounted such that, in the metastable position, the flange is forced towards the supporting plate with maximum force, i.e. that pulling the bottle in the clamping position only makes the lever press the supporting plate more firmly. Fig. 4 shows an embodiment in which gas pipes 40 project from connections 20. Gas pipes 40 project over a length which is virtually equal to the height of the bottles 12 used, but is slightly shorter. Supporting plate 10 is provided with a column 46 which is parallel to the bottles 12 when the bottles have been mounted on supporting plate 10, and projects above the bottles 12. The inner space of column 46 is in connection with the hollow space in supporting plate 10. Gas pipes 40 are connected to internal pipes 42 which continue, via the hollow space of supporting plate 10, into column 46 and terminate in an upper space thereof above the bottles. An auxiliary tube 44 runs from the upper space and then parallel to the tube 16 for tapping the beverage. With faucet 18, auxiliary tube 4-4 is coupled to the air and closed again parallel to the tapping and stopping of the beverage. During the fixing of bottles 12 to connections 20, bottles 12 are pushed around gas pipes 40 to the connections and fixed while gas pipes 40 are directed downwards. Then, the whole is turned around. By operatively enabling air supply via auxiliary tube 44, the upper sp ace of column 46 and gas pipes 40, the creation of a vacuum in bottles 12 is prevented. By having auxiliary tube 44 terminate at faucet 18, any liquid in gas pipes 42 or auxiliary tube 44 can be discharged without any difficulties. In a different embodiment, column 46 is dispensed with and gas pipes 42 are connected to faucet 18. Gas pipes 42 may, for instance, also terminate somewhere on the frame, above the bottles, via a separate air relief cock. In a further different embodiment (not shown), on its upper side, column 46 is provided with a stop cock which is closed during loading and opened after turning supporting plate 10 around to the carrying position. Thus, a leak flow through the vent column is prevented. In this case, no auxiliary tube 44 is needed. Supporting plate 10 is preferably designed with a completely hollow inner space in which connections 20 for the bottles 12 terminate and wherefrom tapping tube 16 taps as well. This simplifies s the construction. However, it will be clear that, without deviating from the invention, use may also be made of a system of pipes which terminate in tapping tube 16 from connections. In this case, the pipes form a hollow space and a more open structure can be used for supporting plate 10. Via a single tapping tube, then liquid can flow from a plurality of bottles 12 to faucet 18 with which the liquid is poured out.