Abstract:
Portable personal air conditioning unit, attachable to the body of a person, with a receptacle for a detachable and therein insertable latent heat storage device with a filler opening containing or receiving a consumable storage medium frozen for the air conditioning operation, having an inlet for air to be delivered past the latent heat exchange device and there to undergo heat exchange, and an outlet for the discharge of the chilled air, as well as a fan, driveable through a power supply provided on the receptacle side, for delivering the air for a self-sufficient operation of the personal air conditioning unit, whereby at least one extraction device is provided for the extraction by the person of thawed, consumable storage medium serving as drinking liquid.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     A personal air conditioning unit portable by a person is known from U.S. Pat. No. 6,427,476 B1. This air conditioning unit is built as a backpack and consists of a large volume, insulated basic case as the container for a chilled substance, ice for instance. Several cooling pipes are led through this case, through which air is blown by a fan located in a separate sealed part of the case, drawing in the surrounding air. After the cooling pipes come into contact with the chilled medium a heat transfer takes place, the air pumped through the cooling pipes being chilled. The cooling pipes terminate in a collar shaped air diffuser, which partially surrounds the person&#39;s neck and through which the chilled air is discharged.  
         [0002]     This portable backpack air conditioning unit can be carried along relatively easily by the user and offers him some cooling in his leisure time, during sporting and other activities as for instance in a work place, where he is active in high ambient temperatures. The purpose of this air conditioning unit is at the same time strictly limited to the provision of personal air conditioning. The user, be it the sports person, hiker or worker for instance, may however develop other needs through their activity, mainly the quenching of thirst as a consequence of high levels of perspiration in particular. The level of this need may be reduced somewhat by the cooling since the general feeling of well being by the persons will be a little higher as a result of the cooling, nevertheless this basic need cannot be totally eliminated.  
       SUMMARY OF THE INVENTION  
       [0003]     The invention therefore relates to a personal air conditioning unit, which is improved in relation to its function or respective usability.  
         [0004]     The invention provides a portable personal air conditioning unit attachable to a person&#39;s body with a receptacle for a detachably insertable latent heat storage device with a filler opening, which contains or accepts a consumable storage medium, frozen for the air conditioning operation. This receptacle is equipped with an intake for the air to be directed past the latent heat storage device and to undergo heat exchange there, and an outlet for the release of the chilled air and also a fan, driveable by a power supply contained within the receptacle, for delivering the air in a self-sufficient operation of the personal air conditioning unit, whereby at least one extraction device is provided for the extraction of thawed consumable storage medium used as a drinking liquid by the person.  
         [0005]     In a preferred embodiment, the invention provides the use of a latent heat storage device, which is removable from the basic receptacle and is filled with a frozen storage medium of a consumable kind. This latent heat storage device is to be placed inside the receptacle by the user of the air conditioning unit after transformation of the storage medium into its frozen state. If cooling is now required as the result of the person&#39;s activity, this will be provided by the receptacle-mounted fan, which draws surrounding air from outside the personal air conditioning unit and delivers it along the side of the closed latent heat storage device, resulting in a heat exchange; the air gets chilled and can as such be supplied to the person. During this process a heat exchange takes place as described, resulting in the frozen storage medium slowly thawing. In the event of the person becoming thirsty as a result of his activity, he has the advantage of being able to extract the thawed storage medium no longer required for chilling the air as such via the extraction device and to consume it as drinking liquid, as long as the storage medium is of a consumable kind as described. Preferably, clear water or any other water-based liquids such as isotonic drinks, juices etc. is used but any consumable and freezable storage medium may be used.  
         [0006]     The advantage of the air conditioning unit in accordance with the invention is that it is multifunctional, as on the one hand it allows adequate personal cooling and on the other is always available as a drink reservoir as the person may extract the thawed portion of the storage medium at any time. For a long period of time the person therefore has a drink reservoir available, the size of which is ultimately determined by the volume of the latent heat storage device. How soon a consumable quantity of liquid is available is ultimately governed by the speed of the thawing process. This is ultimately determined by the intensity of the heat exchange, therefore whether and to what degree the air gets chilled, and by the surface area of the latent heat storage device at which the heat exchange and consequently the thawing process occur. The person will at any rate greatly appreciate that a single unit provides him with adequate cooling and also a drink supply.  
         [0007]     To allow for easy transport of the personal air conditioning unit the receptacle, which preferably is suitably insulated to prevent early thawing of the storage medium or the thawing process being caused by the surrounding air not specifically drawn past the latent heat storage device, is mounted inside a backpack fitted with straps; alternatively it can also be mounted inside a shoulder or waist bag. The personal air conditioning unit can however come in any form, as long as easy transport is assured. External dedicated openings are provided in the air conditioning unit in any case, which are connected to the receptacle openings via suitable connecting pipes so that surrounding air can be drawn in and chilled air can be discharged to the outside by the fan.  
         [0008]     By taking the invention idea further, the latent heat storage device could be designed to contain a liquid accumulator or such that one is separately assigned to it, in which at least part of the thawed storage medium collects and which is fitted with the extraction device. The thawed storage medium over time collects in the liquid accumulator, which normally does not need to be of a dimension to contain the total quantity of thawed storage medium, as frequent extraction and therefore draining of the liquid accumulator occurs as a rule. Should on occasions the liquid accumulator be full however, the thawed liquid will ultimately remain in the latent heat storage device or the storage compartment containing the frozen storage medium and will only flow on into the liquid accumulator when this is drained.  
         [0009]     In this configuration the assigned liquid accumulator could be joined to the latent heat storage device via a valve, which could be operated manually by the user if necessary. It would be practical for this separate liquid accumulator, which is preferably positioned outside the receptacle, to be connected to the latent heat storage device in a detachable way so that both components can be removed separately for cleaning or for respective removal of the latent heat storage device only, when the storage medium requires freezing again; it would be practical to do this in suitable freezing devices (refrigerator or equivalent).  
         [0010]     As an alternative to mounting a separate liquid accumulator inside the backpack, bag or air conditioning unit generally, the liquid accumulator could also form an integral part of the latent heat storage device and be connected to the storage compartment containing the frozen storage medium via one or more drainage openings. This has the advantage that the thawed liquid is continuously drawn away from the storage compartment containing the frozen storage medium and therefore prevents insulation of the frozen storage medium from the storage wall by the thawed liquid contained therein, which limits the chill transfer to the air being delivered through.  
         [0011]     The latent heat storage device itself and, possibly also the separate liquid accumulator assigned to it could have either a solid or a flexible case. The employment of flexible cases in particular is of advantage as this can guarantee that the outer wall of the latent heat storage device will hug the contours of the thawing storage medium continuously, consequently the storage wall will always be lying closely against the frozen storage medium, resulting in an optimum transfer of cooling temperature. This leads to improved cooling efficiency after the insulating layer of thawed liquid described earlier no longer exists as the result of the continuous draining and the storage wall is capable of optimum adaptation to the shape of the frozen storage medium. A solid latent heat storage device can for instance be shaped as a pocket or container, while a flexible latent heat storage device could be shaped as a hose or bag.  
         [0012]     As the thawing rate of the frozen storage medium is naturally higher in the air intake area, due to the higher temperature difference to the outside air here than it is at the air outlet, a functional development of the invention provides for the latent heat storage device to be designed wider in the area facing the air intake compared to that facing the air outlet. This way the variation in the thawing rate can be compensated in a manner that maintains the maximum ice core surface area possible throughout the entire thawing period. A primarily triangular shape would be practical while other shapes such as a teardrop shape ore equivalent are also conceivable. It would be practical if the shape of the receptacle itself would principally match the shape of the latent heat storage device, at least in its frozen state. In this way the frozen latent heat storage device can on the one hand be inserted into the receptacle easily, on the other hand this creates a principally defined airflow path between the inner wall of the receptacle and the outer wall of the latent heat storage device after both have adapted a uniform shape. The receptacle itself can be solid or flexible, even elastic.  
         [0013]     To enable a sufficient airflow an advantageous development of the invention requires that means for the creation of an air slot encompassing the latent heat storage device preferably on all sides are in place on the receptacle side and/or on the storage side. This means will ensure a wide enough gap between receptacle and latent heat storage device to allow a sufficient flow cross section, through which an adequate quantity of air can be delivered. When employing flexible materials in particular in the creation of the latent heat storage device and also the receptacle, it will in practice not always be possible to realize a fully encompassing air slot around the latent heat storage device, however a sufficiently large ventilation cross-section should be provided at all times. One or more spacers for instance can be used to distance the latent heat storage device from the receptacle as means to create the air slot. These could for instance be provided in the form of ledges or ribs or equivalent. It is possible to have a spring suspension of the latent heat storage device with springy spacers, which in the case of a sufficiently solid construction of the receptacle press down on the case of the latent heat storage device and bring this into contact with the frozen storage medium as long as possible, provided the storage case is sufficiently flexible.  
         [0014]     According to the invention, a preferably detachable flexible fluid tube can be attached to the latent heat storage device or the separate liquid accumulator to allow for easy extraction of the thawed storage medium. In the air conditioning unit version as a backpack for instance, this sufficiently long tube will be led over the person&#39;s shoulder so that it is always readily available close to the person&#39;s head and the person can suck in the liquid without difficulty. To this end appropriate clamps can be provided for instance in the area of the straps, in which the fluid tube can be secured when not in use. As an alternative or in addition to this it is also conceivable to provide a sealable drinking or outlet opening on the removable latent heat storage device. To this end however the latent heat storage device needs to be removed from the receptacle. This could for instance be a screw-on cap or equivalent. Such an outlet could of course be provided on the separate liquid accumulator, which then needs to be removed also from the air conditioning unit for tapping. This is particularly easy with a connection between latent heat storage device and liquid accumulator via a valve, which could then be closed to avoid spilling the thawed liquid. At last, as an alternative or in addition a drain valve could also be provided, which can be operated from the outside and through which for instance a drain pipe terminating on the outside of the backpack for example could be opened and closed.  
         [0015]     If a liquid pipe is employed, it would be practical to provide a locking device at its forward end, for instance in the shape of a plug-in cap, a turn-lock fastener or equivalent, to prevent dripping.  
         [0016]     Another functional development of the invention provides a separate removable liquid accumulator be fitted with a filler opening for the purpose of filling with a consumable liquid, which can be extracted through the extraction device. This version has the advantage that the liquid accumulator can be utilised from the start as a drink reservoir. That means that prior to using the device the person will insert the frozen latent heat storage device and also a liquid accumulator filled with a drinking liquid and will couple these. As a consequence of the liquid contained in the liquid accumulator from the start the person has access to a certain liquid reservoir for drinking from the beginning and therefore does not have to wait for the thawing of a sufficient quantity of the storage medium. With advancing cooling operation the liquid accumulator will be continually refilled and serves as drink reservoir.  
         [0017]     As an alternative to the utilisation of the separate liquid accumulator as an initially filled drink reservoir, one version of the invention provides another detachable storage, either filled or capable of being filled with a consumable liquid, which is or can be coupled to the latent heat storage device, the separate liquid accumulator or directly to the extraction device. The person therefore has the opportunity to integrate an additional drinking liquid storage into the backpack for instance and couple this in accordance with the version used to have an adequate liquid reservoir available in this way at the start of operating the air conditioning unit. Naturally, the additional drinking liquid storage can also be used in connection with the removable and initially fillable liquid accumulator.  
         [0018]     A latent heat storage device can achieve remarkable air-cooling by several Kelvin, whereby a latent heat storage device also has sufficient refrigeration capacity. In the event of the person&#39;s individual perception of the cooling being too strong, a practical version of the invention provides for a second air intake for unchilled air to be mixed with the chilled air, where it would be practical for the air intake to be installed in line with an air duct led into the receptacle and terminating in front of the common air outlet. Through this the warm surrounding air can be mixed with the chilled air, so that the air ultimately supplied to the person can be tempered.  
         [0019]     For this it is advantageous that a preferably flap-type or slider-type regulating element is envisaged, through which the aperture of the supply path for the unchilled air is variable. This means that the person can adjust the aperture and therefore the amount of applied unchilled air either manually or, possibly, automatically controlled via the integrated electronics or respective control device. It is particularly advantageous when the regulating element is positioned in such a way that the aperture of the supply path for the unchilled air and the exhaust path of the chilled air for the adjustment of the respective air volumes is variable simultaneously. This too can be done manually or electrically, particularly controlled via the integrated power supply or control device respectively.  
         [0020]     It would be practical to employ the fan already integrated into the receptacle anyway for drawing and delivering of the unchilled air. Alternatively, there is the possibility to provide at least one further fan for drawing and delivering of the unchilled air.  
         [0021]     The embodiment of the invention described earlier allow tempering of the air supplied to the person. So as to make this tempering process as comfortable as possible, a preferred embodiment of the invention provides a thermostat for the person to operate for temperature adjustment of the possibly mixed air supplied to the person. Therefore the person can select a temperature through a suitable device, whereby, subject to this selection, the thermostat automatically controls the air conditioning operation such as the speed of the fan or fans for instance, or the position of the regulating element and by this the mixing operation. For this, one or several suitable sensors are provided, through which for example the temperature of the possibly mixed air is measured at the air outlet, or the fan speed, or the control flap position is determined.  
         [0022]     Furthermore, it is practical in any case if the person can vary the fan speed, with the result that in this way the person can also vary the fan intensity. In case the fan speed is too high and the air therefore blown too hard, one can make the respective adjustment. To this end a control knob for instance or equivalent is provided in an appropriate position.  
         [0023]     Rechargeable battery cells, batteries or fuel cells can supply power. Solar cells mounted on the outside of the device are also possible, however these need to be protected against damage. Furthermore, it would be practical to provide a charging state indicator for the integrated power supply. It is possible to use several energy sources in parallel, for instance rechargeable battery cells and solar cells, through which the rechargeable batteries can be recharged continuously.  
         [0024]     In addition to a charging state indicator for the integrated power supply further means can also be put in place for monitoring the charging state of the latent heat storage device and a charging indicator could be provided. These means monitor for instance the quantity of the remaining frozen storage medium, so as to determine with this information for how long these quantities will be sufficient for adequate cooling.  
         [0025]     This can be done for example by monitoring the weight of the frozen storage medium or the quantity of thawed storage medium drained.  
         [0026]     Several options are conceivable for applying the chilled air to the person. According to one version of the invention, a hose-like air tube is to be coupled to the receptacle outlet supplying the air to the person carrying the air conditioning unit. This could be a tube with a single outlet opening; alternatively it could also have one or more branches so that the air could be applied to the person in several places. The tube or tubes are inserted into existing openings of the person&#39;s clothing (for example collar, sleeves). Alternatively it is possible to provide coupling means at the receptacle outlet for coupling of an air tube supplying air to a piece of clothing with integrated outlet openings worn by the person. This means that in this version the air conditioning unit is coupled to respectively configured clothing (shirt, jacket, trousers, overalls for instance), which contains integrated air tubes and outlet openings in a distributed configuration.  
         [0027]     Where the air tube is only led under the normal clothing it would be practical to fit, preferably in a detachable way, an outlet section to the air tube, made to any form of ductile and preferably skin friendly material and containing several outlet jets. This should primarily be saucer or semi-saucer shaped and contain several multi-directional outlet jets. This possibly palm-sized outlet section could be suitably fastened under the shirt for instance so that it could distribute the air in accordance with the directions of the outlet jets.  
         [0028]     A further option could be the ability to close the air intake and outlet openings provided for the air conditioning unit for instance in a backpack with suitable flaps or equivalent when not in use to prevent dirt from getting into the system.  
         [0029]     Finally the possibility exists to utilise the latent heat storage device or an additional latent heat storage device respectively, which can be placed inside the receptacle in the same way, not for cooling storage but to use it instead for heat storage. To this end the latent heat storage device or additional devices respectively are filled with a heat storage medium. The functions of the personal air conditioning unit are then consequently reversed; it is used to warm the air supplied to the person when the air conditioning unit is for instance being used in a very cold environment. A wax-like substance for instance, which is filled into the latent heat storage device for example in pearl or ball shape, can be used as heat storage medium. By using this heat storage medium, which, similar to the frozen storage medium, also has an adequate heat storage capacity, air warming can take place for a remarkable length of time. Naturally, the drink option is not available in this case. This version however offers in addition to the principal use in accordance with the invention of the personal air conditioning unit as a cooling device and simultaneous drink reservoir the option of using the air conditioning unit in a multifunctional way for personal warming if required. 
     
    
       [0030]     Further advantages, characteristics and details of the invention become evident from the following examples and through the accompanying drawings.  
         [0031]      FIG. 1  is a schematic diagram of an air conditioning unit in accordance with a first embodiment of the invention,  
         [0032]      FIG. 2  is a schematic diagram of an air conditioning unit in accordance with a second embodiment of the invention,  
         [0033]      FIG. 3  is a schematic diagram of an air conditioning unit in accordance with a third embodiment of the invention,  
         [0034]      FIG. 4  is a schematic diagram of an air conditioning unit in accordance with a fourth embodiment of the invention, and  
         [0035]      FIG. 5  is a partial view showing the control elements of an air conditioning unit in accordance with the invention.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0036]      FIG. 1  depicts by way of a schematic drawing an air conditioning unit  1  in accordance with the invention, which is used both to generate chilled air and also to supply drinking liquid. The air conditioning unit  1  is equipped with a backpack-like carry frame  2  with a backpack-like outer case  3 , which usually is made of flexible and mostly waterproof material as in ordinary backpacks, but which can also be made from solid material in knapsack form. The device can be carried on the back with suitable carry straps  4 .  
         [0037]     Inside the backpack-like flexible case, which is made preferably from an insulating material or has an adequate insulation layer  5  respectively (see  FIG. 2 ), a receptacle  6  is placed either firmly integrated or detachable by way of zippers, plug-in fasteners or equivalent. The receptacle  6  can be made from solid plastic material, but it can also be made flexible itself, therefore being variable in its shape and therefore adaptable.  
         [0038]     In the receptacle  6  a latent heat storage device  7  is placed, containing a frozen and wholesome storage medium  8  consumable by the person P carrying the air conditioning unit, which could be for instance frozen clear water or any other water-based drink like an isotonic drink for example or juice or equivalent. While the receptacle  6  can also be made of a thermal insulating material, the case of the latent heat storage device consists of a material allowing a high degree of heat exchange, preferably a very thin plastic. The case can be of a solid or rigid form; as an alternative the employment of a flexible case in the shape of a bag or hose as depicted in  FIG. 1  is also conceivable.  
         [0039]     Through an air intake opening  10  air is drawn in by a fan  11  integrated in the receptacle and, as indicated by the arrows, is delivered past the cold latent heat storage device  7 . This results in a heat exchange; the air is chilled here and passes through the outlet  12  in the shown example to an air pipe  13 , which is led to the person in the collar area, where it is being discharged through suitable air outlet openings. In this way air-cooling can take place for up to several hours, depending on the size of the latent heat storage device, as long as it contains frozen storage medium.  
         [0040]      FIG. 1  illustrates further how in the shown example a fluid pipe  14  attached to the lower section of the latent heat storage device  7  is led over the person&#39;s shoulder to be within the person&#39;s reach. As a result of the heat exchange the frozen storage medium slowly thaws and, since the frozen storage medium is lighter than the thawed one, collects in the lower section of the latent heat storage device  7 . Coupled to this is the fluid pipe  14 , through which the person can now suck in and drink the thawed liquid, if required. It should already be pointed out here that just as the receptacle  6  is detachable, the connection of pipes  13  and  14  to the receptacle and latent heat storage device respectively can be detachable, for example via suitable screw plugs or stop plugs etc. This is of particular advantage in the case of the fluid pipe  14  to allow easy cleaning. In each coupling area a suitable valve or equivalent, which automatically opens when a respective pipe is connected and closes when it gets disconnected, can of course be provided.  
         [0041]      FIG. 2  depicts an air conditioning unit  1   a  in a second version in accordance with the invention in the form of an enlarged schematic diagram. The latent heat storage device  7  is fitted with a filler opening  15 , through which it can initially be filled with the consumable liquid. A liquid accumulator  17  is coupled downstream from the latent heat storage device  7  through a valve  16 ; in the depicted example the fluid pipe  14  coupled to the liquid accumulator is detachable, whereby here also a valve or equivalent could be provided in the coupling area. This liquid accumulator  17  collects the thawed liquid resulting from the heat exchange; it is therefore drawn away from the latent heat storage device. This has the advantage that no insulating fluid layers can gather there. Especially with a flexible case  9  of the latent heat storage device  7 , which could consist of a plastic foil for instance, a tight adherence between a large area of the case wall and the frozen storage medium can therefore be achieved at all times so that an optimum heat or chill exchange respectively can occur with the air delivered past it.  
         [0042]     The liquid accumulator itself serves as a drink reservoir and can be withdrawn from the backpack-type outer case  3  as well as the latent heat storage device  7  through an opening not specifically shown, if required. It is possible to fill it initially with consumable liquid in order to have an adequate drink volume available already at the start of the operation.  
         [0043]     Suitable spacers  18  in the form of ledges are provided at the latent heat storage device in the depicted example for the realisation of an adequate air slot between the latent heat storage device  7  and the receptacle  6  for a sufficiently large flow cross section. The receptacle  6  itself is being kept in place inside the backpack-like outer case  3 , which can have a sufficiently solid shape for example, by suitable spacers  19  of for instance a springy type or by the pressure of an air cushion. Or the receptacle  6  adheres to the spacers  18  by way of its elastic characteristics.  
         [0044]     Beside the central lower air intake  10 , through which the air to be cooled is taken in and which can be closed by a suitable sealing flap  20  when not in use, a further air intake  21  is evidently provided, through which in the depicted example unchilled air can be taken in by the fan  11 . The air intake  21  terminates directly or via a suitable supply pipe above the latent heat storage device  7  in the area of the air already chilled. In this way additional air can be mixed in. Through the flap-like regulating element  22  in the depicted example the air intake  21  can be opened and closed or its aperture generally can be adjusted respectively. The mixed air is then supplied to the person through the air pipe  13 .  
         [0045]      FIG. 2  further depicts the control unit  23 , which shows an integrated power supply  24  for example in the form of rechargeable battery cells or batteries. This will be referred to later. At any rate this is controlling the air conditioning operation.  
         [0046]      FIG. 3  shows a further version of an air conditioning unit  1   b  in accordance with the invention. Here it is apparent that the latent heat storage device  7  in its lower section, which faces the air intake opening  10 , is distinctly thicker than in its upper section, which faces the air outlet opening  12 . This compensates the different thawing characteristics caused by the temperature difference between the air taken in and the air discharged. This means that the latent heat storage device  7  thaws faster in the lower section, which is being blasted by warmer air, than in the upper section; depicted further in dashed lines is the liquid accumulator  17 , the provision of which is optional as is that of a further liquid storage  25 , which can be placed inside the backpack-like outer case  3  and which in the depicted example can be coupled to the liquid accumulator  17  if required. This liquid storage  25  serves, like possibly the liquid accumulator  17  also, as an initially filled liquid reservoir, from which the person can consume liquid even if no air conditioning operation has occurred yet and therefore no thawed storage medium is available.  
         [0047]      FIG. 4  depicts a further version in accordance with the invention, which is essentially equivalent to the version from  FIG. 3 . However here a second fan  26  is provided for taking in warmer surrounding air through the additional air intake  21  for mixing. The control unit  23  or the integrated power supply  24  respectively operate this fan  26  also. This air intake too can be closed by a locking flap  27  if required, as is also possible for the air outlet  12  by the locking flap  28  with the air pipe  13  disconnected. Depicted further is the mouthpiece  29  attached to the fluid pipe  14 , which for instance could also serve as plug for the fluid pipe  14  to prevent undesired loss of liquid through dripping.  
         [0048]      FIG. 5  finally shows in a basic view the control panel  30  of the control unit  23 , which could for instance be positioned in the freely accessible rear wall of the backpack-like case  3 ; it is equally possible to have it positioned on the side so that the person could operate it with the unit strapped on, if required.  
         [0049]     Depicted is the ON/OFF switch  31 , which requires to be pushed to start the air conditioning unit. With this at least the fan  11  will automatically start to draw in air and to produce cooling. Shown further is a not closer defined thermostat  32 , comprising a selector switch  33 , with which a desired temperature indicated in the display  34 , can be selected. The control unit  23  is capable of automatically adjusting the temperature to the desired level, which is governed by the automatic control of the operation of fan  11  for varying the volume of the air taken in or, if installed, of the second fan  26  or the regulating element  22  respectively, through which the aperture of the air pipe supplying the unchilled air can be varied. All required elements are automatically driven to adjust the selected temperature.  
         [0050]     Finally a switch  35  is provided, through which the person can for instance manually adjust the regulating element  22 , for temperature control when the thermostat-controlled operation is not desired. Furthermore a switch  36  is provided, with which the speed of fan  11  and the second fan  26 , if installed, can be adjusted in order to vary the blower intensity. This switch  36  can for instance be realized as a combined rotary/press switch to allow switching over from driving the fan  11  to driving the second fan  22  by pushing the switch  36 . The ability to drive both through this is indicated by the symbol “U 1/2 ”.  
         [0051]     Further depicted are several solar cells  37 , which aid the power supply. Through them the rechargeable battery cells  38 , which form the power supply, can be recharged continuously. Furthermore, a charging state indicator  39 , for example as a LED, for the power supply and an equivalent charging state indicator  40  for the latent heat storage device are provided.  
         [0052]     The invention is not limited to the versions described. It is possible for instance to realize the case  3  also as a waist or hip bag, which is to be worn like a belt and therefore designed a little smaller. The version in the form of a shoulder bag is also conceivable. Furthermore it is possible to provide instead of the air pipe  13  as shown in the drawings, one that has at its end a clearly expanding outlet segment, which is equipped for example with outlet jets of different radial direction, through which the chilled air can be blown out. This flat outlet segment for example can be pushed under the clothing so that the body can be cooled. It needs to be pointed out eventually that for the operation of the thermostat suitable sensor elements for registering the relevant parameters like actual temperature at the air outlet, speed of the fan or fans if necessary and also the position of the regulating element can be provided. Adequate, preferably electrical adjustment means for varying the position of the regulating element  22  in the form of a small electric motor or equivalent are provided in addition, naturally. However a mechanical motion coupling with the switch  35  is also conceivable.  
         [0053]     Finally there is the option to utilise the personal air conditioning unit not as a combined cooling and drink reservoir unit but as a warming device, combined with the drink option. This will be useful for instance when the unit is being employed in a very cold environment. In this case it is conceivable to fill the latent heat storage device (or possibly a further additional latent heat storage device) with a hot and consumable storage medium, which serves to warm the air delivered past it. When the storage medium cools in the course of the warming operation as the result of the heat exchange, the liquid can be extracted and consumed. It is conceivable for example to fill it with hot water or hot tea or any other hot drink. Although the heat storage capacity or respectively the introducible energy content of the hot storage medium is evidently lower than that of the frozen storage medium, it is nevertheless possible to achieve warming of the air over a longer period of time, which will be appreciated by the user. In this version the separate liquid accumulator option is obviously not required since the storage medium presents in its liquid form anyway. Nevertheless all other invention versions, which have been described in the earlier specifications for the use as a cooling device, have to be provided appropriately in this case also.  
         [0054]     As an alternative to the use of the described unit as a heating device by employing an also consumable storage medium, the option exists in the way of an air conditioning system to provide a further latent heat storage device, which can be placed inside the receptacle if required due to the interchangeability, and which contains a heat-storing, non-consumable medium such as a wax-like medium for example. This could for instance be heated in a microwave oven or a stove or equivalent and be placed in the receptacle in a hot state. In this way the personal air conditioning system can equally be used as a heating device for warming the air, although in this case the drink option is not available. This could be possible if for instance a separate liquid storage would be provided or if the liquid accumulator, which in this version would not be required, would initially be filled with a consumable liquid. In this version however the liquid accumulator is not coupled to the latent heat storage device. In this way the possibility exists to realize a warming of the air, because of the use of a wax-like substance for a clearly longer period of time. Such an additional latent heat storage device could for example be bought as an aftermarket accessory to the personal air conditioning unit in accordance with the invention.  
         [0055]     As no extraction of the storage medium occurs in this case, a refilling of this latent heat storage device is not required. In this case too the personal air conditioning unit displays all the characteristics described in connection with its use as a cooling device.