Improvements in or relating to a machine for the preparation of beverages

0001The present invention relates to improvements in or relating to a machine for the preparation of beverages.

0002Beverage preparation systems for producing beverages such as coffee and tea are known in the art. One example is described in <patcit id="pcit0001" dnum="WO2004064585A"><text>WO2004/064585</text></patcit> which teaches a beverage preparation system suitable for producing a wide range of beverages such as coffee, tea, hot chocolate, espresso and cappuccino.

0003Attempts have been made to produce alternative beverage preparation systems capable of dispensing both hot and cold beverages. However, such systems rely on the provision of a relatively high capacity, on-demand cooler, such as a flash cooler, for cooling relatively large volumes of water very quickly to a suitable temperature when a cold beverage is to be dispensed. Alternatively, the systems provide high capacity coolers for lowering the temperature of the water in the whole storage reservoir to the required temperature for cold beverages. High capacity coolers are those able to quickly cool either relatively large volumes of water by a moderate amount or to produce a relatively large temperature change in smaller volumes of water. These systems have disadvantages, including the problem that the high capacity coolers are large, noisy and contain a refrigerant gas as part of the cooling circuit. This makes the systems bulky, expensive and difficult to recycle. Thus they are unsuitable for use in a domestic setting.

0004The present invention provides a beverage preparation machine for dispensing beverages as set out in claim 1.

0005The machine may further comprise a second reservoir station and a second reservoir for containing an aqueous medium, the second reservoir being connectable to said second reservoir station.

0006The auxiliary module may be connected inbetween the second reservoir and second reservoir station:

0007The auxiliary module may be selected from a chilling module, a pre-heating module, an aqueous medium filtration unit, a disinfection module and a telemetry unit.

0008A heater may be provided in fluid communication with the first reservoir station and or the' second reservoir station.

0009Preferably the first reservoir contains aqueous medium at ambient temperature.

0010Preferably the second reservoir contains aqueous medium at a temperature of between 5 and 30 degrees Celsius below ambient temperature. More preferably, the aqueous medium is at a temperature of between 5 and 15 degrees Celsius below ambient temperature. The ambient temperature will vary according to the local climate in which the machine is used. Preferably, the second reservoir contains aqueous medium at a temperature of between 4 and 15 degrees Celsius.

0011The chilling module may comprise a recirculation mechanism for diverting aqueous medium cooled by the chilling module back to the reservoir.

0012The second reservoir may be thermally insulated.

0013Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: <ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">Figure 1</figref> is a front perspective view of a first embodiment of beverage preparation machine according to the present invention;</li><li><figref idref="f0001">Figure 2</figref> is a rear perspective view of the machine of <figref idref="f0001">Figure 1</figref>;</li><li><figref idref="f0002">Figure 3</figref> is a schematic representation of the machine of <figref idref="f0001">Figure 1</figref>;</li><li><figref idref="f0003">Figure 4</figref> a front perspective view of a second embodiment of beverage preparation machine according to the present invention; .</li><li><figref idref="f0003">Figure 5</figref> is a rear perspective view of the machine of <figref idref="f0003">Figure 4</figref>;</li><li><figref idref="f0004">Figure 6</figref> shows a series of perspective views of the machine of <figref idref="f0003">Figure 4</figref> illustrating the fitting of two auxiliary modules;</li><li><figref idref="f0005">Figure 7</figref> is a schematic representation of the machine of <figref idref="f0003">Figure 4</figref>;</li><li><figref idref="f0006">Figure 8</figref> shows a series of perspective views of a third embodiment of beverage preparation machine according to the present invention illustrating the fitting of two water tanks and an auxiliary module;</li><li><figref idref="f0007">Figure 9</figref> is a schematic representation of a disinfection system for us with the prior embodiments; and</li><li><figref idref="f0008">Figure 10</figref> is a schematic representation of a fourth embodiment of beverage preparation system according to the present invention.</li></ul>

0014<figref idref="f0001 f0002">Figures 1 to 3</figref> show a first embodiment of beverage preparation machine according to the present invention. The beverage preparation machine is of the general type described and shown in <patcit id="pcit0002" dnum="WO2004064585A"><text>WO2004/064585</text></patcit> except for modifications as described below relating to the present invention as defined by the appended claims. <patcit id="pcit0003" dnum="WO2004064585A"><text>WO2004/064585</text></patcit> describes fully the basic design and functioning of the beverage preparation machine and the design and function of the beverage cartridges used with the machine. These aspects will not be described in detail here except where relevant to the present invention. The contents of <patcit id="pcit0004" dnum="WO2004064585A"><text>WO2004/064585</text></patcit> are incorporated herein by reference.

0015It will be appreciated that the invention may find application with other types of beverage preparation machine and for the purposes of the present invention there is no requirement for the beverage ingredients to be derived from cartridges or delivered in a single-dose format.

0016As shown in <figref idref="f0001">Figures 1 and 2</figref> the beverage preparation machine 201 generally comprises a housing 210 containing a water heater 225, a water pump 230, a dispensing valve 235 with an air inlet 236, a control processor, a user interface 240 and a cartridge head 250. The cartridge head 250 in turn generally comprises a cartridge holder for holding, in use, the beverage cartridge, cartridge recognition means and inlet and outlet piercers, for forming, in use, an inlet and an outlet in the beverage cartridge.

0017The front half 211 of the housing 210 comprises a dispense station 270 where dispensation of the beverage takes place.

0018The machine user interface 240 is located on the front of the housing 210 and comprises a start/stop button 241. The start/stop button 241 controls commencement of the operating cycle and is a manually operated push-button, switch or similar. The button 241 may also be used to manually stop the operating cycle.

0019A rear half 212 of the housing 210 provides a recess 214 for the attachment of first and second water tanks 220, 280.

0020The first water tank 220 may be made from a transparent or translucent material to allow a consumer to view the quantity of water remaining in the tank. Alternatively, the first water tank 220 may be made from an opaque material but have provided a viewing window therein. In addition, or in place of the above, the first water tank 220 may be provided with a low level sensor which prevents operation of the water pump 230 and optionally triggers a warning indicator, such as an LED, when the water level in the tank descends to a preselected level. The first water tank 220 preferably has an internal capacity of approximately 1.5 litres.

0021The first water tank 220 is connected in use to a first water tank station 120. The first water tank 220 comprises a generally cylindrical body 221 which may be right circular or a frustum as desired for aesthetic reasons. The tank comprises an open upper end forming an inlet for filling the tank with water which is closed off in use by a manually removable lid 222. An outlet is provided towards a lower end of the tank. The outlet contains a valve which is biased into a closed position when the first water tank is removed from the first water tank station 120. The outlet may also be provided with a filter to prevent ingress of solid particulates into the internal parts of the machine. The first water tank station 120 comprises a base plate 121 shaped to receive a lower end of the first water tank 220. The base plate 121 is provided with a valve connector 122 that matingly connects with the outlet valve of the first water tank 220 when the tank is placed on the base plate. Connection of the tank 220 to the station 120 opens the valve and allows for water flow therethrough.

0022As shown in <figref idref="f0002">Figure 3</figref>, a conduit 123 extending internally from the valve connector 122 communicates with the water heater 225.

0023The beverage preparation machine 201 is provided with a second water tank station 180. The second water tank station 180 comprises a base plate 181 having a valve connector 182 in the same manner as the first water tank station 120. The second water tank 280 is locatable on the second water tank station 180. The second water tank 280 is provided with an outlet valve of the same type as the first water tank and connects to the valve connector in the same manner as described above. The construction and materials of the second water tank 280 are preferable the same as those of the first water tank 220.

0024The base plates 121 and 181 are preferable formed as one piece having separate indentations marking the locations of the first and second water tanks 220, 280.

0025A conduit 183 extends internally from the valve connector 182 of the second water tank station to the dispensing valve 235.

0026The water pump 230 is a volumetric displacement pump that creates sufficient suction head to draw water from the tanks through the heater and the dispensing valve 250. Preferably a peristaltic type pump is used such that each revolution delivers a known volume of water. The water pump 230 provides a maximum flow rate of 900 ml/min of water at a maximum pressure of. 2.5 bar. Preferably, in normal use, the pressure will be limited to 2 bar. The flow rate of water through the machine can be controlled by the control processor to be a percentage of the maximum flow rate of the pump by speed control. Preferably the pump can be driven at any of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100% of the maximum rated flow rate. The accuracy of the volume of water pumped is preferably + or - 5% leading to a + or - 5% accuracy in the final volume of the dispensed beverage where a peristaltic pump is used the volume delivered can be determined by the number of revolutions. Alternatively, for example where a peristaltic pump is not used, a volumetric flow sensor (not shown) can be provided in the flow line either upstream or downstream of the water pump 230. Preferably, the volumetric flow sensor would be a rotary sensor.

0027The dispensing valve, 235 preferably comprises an assembly of two electrically operated solenoid change-over valves with associated non-return valves as shown schematically in <figref idref="f0002">Figure 3</figref>. In order to correctly route water through the machine from the first or second water tanks to the cartridge head the respective solenoid valve of the dispensing valve 250 is selected by the control processor before flow commences.

0028The water heater 225 has a power rating of 1550 W and is able to heat water received from the water pump 230 from a starting temperature of approximately 20°C to an operating temperature in the range of around 88 to 94°C in under 1 minute. Preferably the dwell time between the end of one operating cycle and the heater 225 being able to commence a subsequent operating cycle is less than 10 seconds. The heater maintains the selected temperature to within + or - 2 °C during the operating cycle. Preferably the water for the operating cycle may be delivered to the cartridge head 250 at 88°C, 91°C or 94°C. The heater 225 is able to quickly adjust the delivery temperature within the range 88°C or 94°C. The heater 225 comprises an over-temperature cut-off which shuts off the heater if the temperature exceeds 98 °C.

0029The dispensing valve 235 receives water supply inlets from the water heater 225 and the second water tank 280 as shown in <figref idref="f0002">Figure 3</figref>. In addition, the air inlet 236 allows air to be pumped to the cartridge head 250. If required a separate air compressor may be incorporated into the air supply route. The water/air outlet 237 from the dispensing valve 235 connects to the water pump 230. In turn, the water pump 230 connects to the cartridge head 250.

0030The control processor of the beverage preparation machine comprises a processing module and a memory. The control processor is operatively connected to, and controls operation of, the water heater 225, water pump 230, dispensing valve 235 and user interface 240.

0031In use, the first water tank 220 is used to provide water for hot drinks and the water passes through the water heater 225 on the way to the cartridge head 250. The second water tank 280 is used to provide water for cold drinks or drinks served at ambient temperature and the water does not pass through the water heater 225. The water in the second water tank 280 may be chilled before it is poured into the tank. However, preferably, the tank, containing the water, may be chilled in a refrigerator. Preferably the water in the second water tank 280 when connected to the secondary water tank station is at between 5 and 30 degrees Celsius below ambient or room temperature, more preferably at between 5 and 15 degrees Celsius below ambient. The shape and size of the tank allows the tank to be fitted into a domestic refrigerator door when disconnected from the beverage preparation machine.

0032The first and second water tanks 220, 280 may be interchangeable on the first and second water tank stations 120, 180. In other words, one design of tank may be used for fitting to the first and second water tank stations 120, 180.

0033<figref idref="f0003 f0004 f0005">Figures 4 to 7</figref> show a second embodiment of beverage preparation machine 201 according to the present invention. As with the first embodiment, the machine comprises first and second water tanks 220, 280 and first and second water tank stations 120, 180. As shown in <figref idref="f0003">Figure 4</figref> the design of the housing 210 is of a different shape but the function of the components of the machine is the same as that of the first embodiment described above except where noted differently below.

0034As shown in <figref idref="f0004">Figure 6</figref> the beverage preparation machine is provided with one or more auxiliary modules. In the illustrated embodiment two auxiliary modules are shown mounted to the first and second water tank stations 120, 180. A pre-heating module 320 is mounted on the first water tank station 120 between the first water tank 220 and the base plate 121. A chilling module 380 is mounted on the second water tank station 180 between the second water tank 280 and the base plate 180. It should also be noted that <figref idref="f0004">Figure 6</figref> shows an optional arrangement where the beverage preparation machine is provided with a single water tank 290 of double capacity which is located on both the first and second water tank stations.

0035The auxiliary modules 320, 380 are mounted in line with the first and second water tanks. A lower face of each auxiliary module matches the interface of the water tanks stations, whilst an upper face of the auxiliary modules is shaped to receive the first or second water tanks. Both the upper and lower faces of the auxiliary module are provided with suitable valve connectors for mating with the valve connectors of the water tank stations and water tanks. This arrangement is particularly suitable where the auxiliary module comprises a chilling unit or a pre-heating unit. A filtration unit may also be used in this configuration.

0036<figref idref="f0005">Figure 7</figref> illustrates schematically the internal configuration of the second embodiment. The arrangement of the pump, water heater and dispensing valve are the same as in the first embodiment. As shown, the pre-heating module 320 comprises a heater 321. The chilling module 380 comprises a thermoelectric cooler (TEC) 381 which receives water from the second tank 280 via a tank outlet 383, cools the water and then re-circulates the water back to the second tank 280 via a tank inlet 384. Motive force for the re-circulation is provided by a dedicated pump 382 within the chilling module 380. When required water exits the chilling module 380 via valve 385. Other types of peltier heat pump or similar device may be used instead of the TEC 381.

0037In use, when a cold beverage is required, water is pumped from the second water tank 280 by the pump 230 to the cartridge head 250. Due to the presence of the chilling module 380 the water in the second tank 280 is maintained in a chilled state.

0038The chilling module 380 may be used to chill water in the second tank 280 that is initially at ambient or room temperature or may be used to maintain the temperature of water in the second tank 280 which has previously been chilled in a refrigerator.

0039The pre-heating module 320 may be used to heat water taken from the first tank 220 at ambient temperature by a set amount before passing the water to the main heater 225 in the machine housing.

0040As an alternative, the second tank may itself comprise a chilling mechanism, such as a TEC, as an integral part of the tank.

0041<figref idref="f0006">Figure 8</figref> shows a third embodiment of the present invention wherein the beverage preparation machine 201 is provided with an auxiliary module station 300 as well as the first and second water tank stations 120, 180. The auxiliary module station 300 is used to mount auxiliary modules in parallel to the first and second water tanks rather than in line with the tanks.

0042The auxiliary module station 300 comprises power and fluid connections. The auxiliary module station 300 may be rotated in between a storage position, in which the station is hidden from view below the first and second water tank stations, and an operating position as shown in <figref idref="f0006">Figure 8</figref> in which the station is accessible and is position rearward of the first and second tank stations. In alternative, non-illustrated versions, the auxiliary module station 300 may be moved between storage and operating positions by means of a translational movement, such as a sliding motion, or by being located on a flip-down panel which is lowered when the auxiliary module is to be used.

0043The auxiliary module 300 may be any of a chilling module, a pre-heating module, a water filtration unit, a disinfection module, a telemetry device or similar as described above.

0044<figref idref="f0007">Figure 9</figref> illustrates a modification to the system which can be utilised in any of the above embodiments. An ultra-violet (UV) chamber 501 is provided as part of a water recirculation system. As shown water is recirculated from the second tank 280 by means of pump 382 and three-way valve 500 back to the second tank 280 via the UV chamber 501. This recirculation continues when water is not required to be transferred to the cartridge head 250. When water is required to dispense a beverage then this is diverted to the cartridge head 250 by use of the three-way valve 500.

0045The UV chamber 501 comprises a housing 503 and a plurality of UV emitting elements 502 which are focussed to illuminate the water passing through the chamber 501 with light in the UV range. Preferably, the piping used for conveying the water through the chamber 501 is formed from fluoroethylene polymer (FEP) to allow for good UV transmission across the piping. The UV emitting elements 502 comprises UV-emitting light emitting diodes (LEDs). The LEDs emit UV in a chosen wavelength between 250 and 320 nanometres (nm). The LEDs may have a relatively low power output compared with low-pressure mercury discharge UV lamps since the recirculation of the water through the chamber 501 many times increases the total UV exposure time of the water. In addition, the LEDs may be arranged to have a small focus area by the use of a suitable lens arrangement to enhance the disinfection effect. This allows less expensive and smaller UV LEDs to be utilised.

0046Preferably, the tank 280 or the water contained therein may be illuminated by a portion of the UV output of the LEDs which has been filtered. The tank 280 may be formed, or contain, a material which fluoresces when exposed to UV light.

0047The use of UV light to disinfect the water used in the system may be used for water recirculation in the first tank 220 and or the second water tank 280 irrespective of whether the water is also subject to chilling, heating or discharged at ambient temperature. The UV chamber 501 may be formed as part of the recirculation piping of a chilling module formed as part of the machine or as part of another auxiliary module connectable to one of the water or auxiliary module stations. Each reservoir station may be provided with an inline UV chamber 501 if required.

0048The UV chamber 501 may be formed as part of the main housing of the machine or as part of a separate, connectable, auxiliary module. The UV chamber 501 and recirculation mechanism may be formed as part of a disinfection module per se or as part of a chilling module.

0049<figref idref="f0008">Figure 10</figref> illustrates a fourth embodiment of system. In this system the beverage preparation machine 201 comprises a single reservoir station and two water tanks. The first water tank 220 contains water at ambient temperature and is to be used to prepare hot beverages. The second tank 280 contains water 400 at below ambient temperature and is used to prepare cold beverages. The tanks 220, 280 are interchangeable and swapped on and off the reservoir station as required. Advantageously, the second tank, when not mounted to the beverage preparation machine 201 is preferably stored in a refrigerator in order to create and maintain a chilled volume of water. In this way the system can quickly be used to make both hot and cold beverages without the necessity for chilling apparatus within the housing of the beverage preparation machine.

0050Preferably the second water tank 280 is thermally insulated and may be provided with a carrying handle. It may also be suitably shaped to fit within standard compartments of a refrigerator such as a door pocket.

0051In use of any of the first to third embodiments described above, an auxiliary module as required is mounted to the auxiliary module station or the first or second water tank station as appropriate. In addition, one or other or both of the first and second water tanks are positioned on the respective first and second water tank stations as appropriate.

0052The water for the beverage is sourced from the first or second water tank depending on the type of beverage to be dispensed. For example, where a chilled beverage is required the water is sourced from the second tank which may contain water pre-chilled in a refrigerator, or contain water chilled by a chilling module or integrated TEC. Where a hot beverage is required the water is sourced from the first tank and the water is passed to the heater 225, optionally via a pre-heating module.

0053The basic operational behaviour of the machine 201 thereafter for any of the embodiments set out above is described fully in <patcit id="pcit0005" dnum="WO2004064585A"><text>WO2004/064585</text></patcit>.

0054From the above it will be understood that in the present invention the auxiliary modules where present may be positioned in line or parallel to one or more tanks containing water for forming beverages. One, two or more auxiliary modules may be used in combination with one, two or more water tanks depending on the desired combination of functions. It will also be understood that the various types of auxiliary module described are given as examples only and may be used with one or more of the embodiments of beverage machine described above. The auxiliary modules and water tanks of the above embodiments may be used with beverage preparation machines having one, two or more reservoir stations.