Abstract:
In order to provide a container for the cooling and/or cold storage of foods and/or beverages which comprises at least one storage tank for a multi-phase flowable cooling medium wherein the cooling effect is still as uniform as possible over the entire height of the storage tank even when the multi-phase flowable cooling medium has been stored in the storage tank for a long period of time, it is proposed that the storage tank be divided into a plurality of storage tank segments which are separated from each other by partition walls which extend horizontally or are inclined to the vertical.

Description:
RELATED APPLICATION 
     This application is a continuation application of PCT/EP2007/007937 filed Sep. 12, 2007, the entire specification of which is incorporated herein by reference. 
    
    
     FIELD OF DISCLOSURE 
     The present invention relates to a container for the cooling and/or cold storage of foods and/or beverages which comprises at least one storage tank for a multi-phase flowable cooling medium. 
     BACKGROUND 
     From DE 202 04 974 U1, there is known a food-transporting carriage for meal distribution systems which comprises vertical plate-like hollow bodies in the form of canaliculated walls which are adapted to be filled with a pumpable ice-water-mixture. 
     Vertically aligned storage tanks for multi-phase flowable cooling media have the disadvantage that uniform cooling over the entire height of the vertically aligned storage tank can no longer be ensured after a certain period of storage. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a container of the type specified hereinabove in which the cooling effect is still as uniform as possible over the entire height of the storage tank even when the multi-phase flowable cooling medium has been stored in the storage tank for a long period of time. 
     In accordance with the invention, this object is achieved in the case of a container incorporating the features indicated in the first part of claim  1  in that the storage tank is divided into a plurality of storage tank segments which are separated from each other by means of partition walls that either extend horizontally or are inclined to the vertical. 
     When the storage tank of the container in accordance with the invention is filled with the multi-phase flowable cooling medium and decoupled from the external supply source for the cooling medium, the multi-phase cooling medium begins to separate out and the lighter phase (an ice phase for example) floats on the heavier phase (a liquid phase for example) in each of the storage tank segments. 
     Since, however, a plurality of storage tank segments are arranged one above the other and are separated from each other by the partition walls, the lighter phase does not accumulate in its entirety at the upper end of the storage tank, but rather, several accumulations of the lighter phase are formed and these are distributed over the height of the storage tank, this being the reason why the storage tank remains uniformly cold over its entire height since the lighter phase can only float up to the next higher partition wall in each case. 
     Preferably, the partition walls run substantially horizontally between storage tank segments that are arranged one above the other. 
     The plurality of storage tank segments of the storage tank in accordance with the invention are preferably arranged substantially vertically one above the other. 
     In a preferred embodiment of the invention, the storage tank is divided into at least three, and preferably into at least six storage tank segments. 
     If the container comprises at least one receiving space for holding the foods and/or beverages requiring cooling, then the storage tank preferably forms a boundary wall of such a receiving space so that the foods and/or beverages in the receiving space can be subjected directly to the cold from the storage tank. 
     In particular, there is provided thereby a very large heat-transferring surface area between the storage tank and the receiving space for the foods and/or beverages requiring cooling. 
     In a preferred embodiment of the invention, provision is made for the storage tank to comprise at least one side wall that is provided with projections upon which trays, food containers and/or beverage containers can be placed. 
     In this case, the storage tank of the container fulfils several functions: it serves as a storage tank for the multi-phase flowable cooling medium and also as a support wall for the placement of trays or containers when it is provided with beadings for example. 
     A particularly simple structure for the container in accordance with the invention results in the case where the storage tank comprises at least a first side wall and a second side wall, wherein at least one of the side walls comprises at least one projection which abuts the other respective side wall in sealing manner. Such a projection can thus form a partition wall which separates two mutually adjacent storage tank segments from each other. 
     In particular, provision may be made for both the side walls of the storage tank to be fixed together in the vicinity of the at least one projection. 
     For example, provision may be made for both the side walls of the storage tank to be welded and/or soldered to one another in the vicinity of the at least one projection. 
     In order to enable the storage tank to be filled with fresh cooling medium in a simple manner and also to enable used cooling media to be removed from the storage tank in a simple manner, it is of advantage if the storage tank comprises at least one connecting channel which interconnects two storage tank segments. 
     In particular, provision may be made for the storage tank to comprise at least one connecting channel by means of which a first storage tank segment is connected to a more highly located second storage tank segment, and at least one second connecting channel by means of which the first storage tank segment is connected to a lower lying third storage tank segment. 
     In order to ensure that the freshly supplied cooling medium flows completely through the first storage tank segment when filling the storage tank with fresh cooling medium, it is of advantage if the first connecting channel and the second connecting channel are arranged on mutually opposite sides of the storage tank. 
     In order to ensure that the fresh cooling medium being supplied to the storage tank mixes as thoroughly as possible with the stored cooling medium, it is expedient for the storage tank to comprise a plurality of storage tank segments through which the cooling medium can flow in meandering manner. 
     In order to prevent the lighter phase of the multi-phase cooling medium that is floating on the surface thereof from leaving a storage tank segment and passing through a connecting channel to a more highly located storage tank segment, it is of advantage if the at least one connecting channel comprises at least one inlet opening through which the cooling medium can enter the connecting channel from a storage tank segment, wherein the inlet opening is spaced in the downward direction from a partition wall which bounds this storage tank segment in the upward direction. Consequently, the lighter phase of the multi-phase cooling medium that is floating on the heavier phase can be arranged entirely above the inlet opening so that, in the storage operational mode of the storage tank, this lighter phase will not enter the respectively more highly located storage tank segment through the connecting channel. 
     Preferably, the spacing of the inlet opening from the partition wall located thereabove corresponds at least approximately to a quarter of the height of the storage tank segment concerned. 
     In order to enable the storage tank to be filled with fresh cooling medium in a simple manner, the container preferably comprises at least one cooling medium in-flow line through which the cooling medium can be supplied to the lowermost storage tank segment of the at least one storage tank. 
     In order to enable the used cooling media to be extracted from the storage tank in a simple manner, the container preferably comprises at least one cooling medium return line through which the cooling medium is removable from the uppermost storage tank segment of the at least one storage tank. 
     The container in accordance with the invention preferably comprises no devices of any type whatsoever for producing or for cooling the flowable cooling medium. 
     In order to enable the storage tank of the container to be filled with the multi-phase flowable cooling medium, it is therefore of advantage if the container comprises at least one cooling medium in-flow connector for supplying cooling medium from an external source of cooling medium to the at least one storage tank. 
     Furthermore it is expedient, if the container comprises at least one cooling medium return-flow connector for carrying away the cooling medium from the at least one storage tank to an external cooling medium sink. 
     The at least one storage tank is preferably divided into a plurality of storage tank segments located vertically one above the other. 
     In a preferred embodiment of the container in accordance with the invention, provision is made for the container to be mobile. 
     This can be achieved, in particular, in that the container is provided with castors. 
     Furthermore, provision is preferably made for the multi-phase flowable cooling medium to be a binary ice. 
     Binary ice (also known as flow ice or smart ice) is a flowable and pumpable, two-phase mixture consisting of a solid ice phase and a liquid water/alcohol phase (which thus contains water and an alcohol serving as a substance for reducing the freezing point) in which the ice phase is suspended. 
     The melting temperature of the ice phase depends upon the type of alcohol being used (ethanol for example) and on the proportion of alcohol that has been selected. 
     If this binary ice is used for cooling goods which require cooling, then the binary ice absorbs heat from the goods being cooled and converts it into latent heat of the binary ice, in that a portion of the ice phase of the binary ice is melted without thereby changing the temperature of the binary ice, at any rate, insofar as the ice phase of the binary ice has not completely melted. 
     Due to these properties and because it is capable of being pumped, binary ice is ideally suitable for being filled into static or mobile containers as a latent cooling medium. 
     Furthermore, due to the proportion of ice therein, the binary ice has a comparatively high specific energy density. 
     The container in accordance with the invention works independently of mains power and is environmentally friendly. 
     The container does not include an integrated refrigerator and for this reason the container in accordance with the invention is capable of being passed through a washing plant, it is easy to maintain and is not liable to malfunction and it only occupies a small amount of space. 
     Due to the absence of pumps and/or fans in the container in accordance with the invention, there is no noise nuisance whatsoever when the container is operational so that the container in accordance with the invention is especially suitable for use in hospital wards. 
     The container in accordance with the invention produces no waste heat and does not therefore produce an increase in the building load. 
     The container in accordance with the invention is very reliable in service since a whole day&#39;s supply of the multi-phase flowable cooling medium can be pre-stored in its storage tank and it is therefore generally possible to effect maintenance and repair work without interfering with its operation. 
     An additional pre-cooling of the container in accordance with the invention is not necessary since it is immediately ready for use independently of a mains electricity supply due to the introduction of the multi-phase flowable cooling medium into the container. 
     Consequently, refrigerated depositories (goods stations) or means of transport (refrigerated lorries) and refrigerated regeneration stations are not needed for the containers in accordance with the invention, this thereby significantly increasing the economical effectiveness thereof. 
     The container in accordance with the invention is particularly suitable for use in the field of food distribution in institutional catering, especially in centralised kitchens, large hospitals etc. 
     Further features and advantages of the invention form the subject matter of the following description and the graphical illustration of an exemplary embodiment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a schematic perspective illustration of a mobile food transporting container; 
         FIG. 2  a schematic perspective illustration of the cooling medium storage tanks in the food transporting container depicted in  FIG. 1 ; 
         FIG. 3  a schematic perspective illustration corresponding to 
         FIG. 2  after the right-hand and two central cooling medium storage tanks have been removed; 
         FIG. 4  a schematic perspective illustration of the left-hand cooling medium storage tank depicted in  FIG. 3 ; 
         FIG. 5  a schematic perspective illustration of a left-hand side wall of the cooling medium storage tank depicted in  FIG. 4 ; 
         FIG. 6  a schematic plan view of the inside of the side wall depicted in  FIG. 5 ; and 
         FIG. 7  a schematic vertical section through a lower region of the cooling medium storage tank depicted in  FIG. 4 . 
     
    
    
     Similar or functionally equivalent elements are designated by the same reference symbols in each of the Figures. 
     DETAILED DESCRIPTION OF THE INVENTION 
     A mobile food transporting container bearing the general reference  100  in  FIGS. 1 to 7  comprises a base plate  102  having castors  104  that are rotatable about horizontal axes mounted on the lower surface of the base plate  102  and a substantially cuboidal carcass  106  disposed on the upper face of the base plate  102 . 
     The carcass  106  comprises a horizontal base plate  108  (see  FIG. 3 ), a vertical rear wall  110 , a storage tank assembly  112  (see  FIGS. 2 and 3 ) for storing a flowable cooling medium, an outer cladding  114  and thermal insulation which is arranged between the outer cladding  114  and the storage tank assembly  112 . 
     Two gripping bars  116  that can be held by the user for pushing and guiding the mobile food transporting container  100  are arranged on each of the two external walls of the outer cladding  114 . 
     The storage tank assembly  112  for storing a flowable cooling medium is illustrated in full in  FIG. 2  and comprises four vertical storage tanks  118  namely, two outer vertical storage tanks  118   a  and two inner vertical storage tanks  118   b , wherein an outer storage tank  118   a  and an inner storage tank  118   b  form the respective lateral boundary walls of a holding chamber  120  that is used for holding foods and/or beverages requiring cooling, and also an upper horizontal storage tank  122  which rests upon the upper ends of the vertical storage tanks  118  and forms a cover wall for the two holding chambers  120 . 
     At the front of the food transporting container  100 , the holding chambers  120  are closed by means of a respective heat insulating door  124  which is mounted on one of the vertical storage tanks  118  such that it can pivot about a vertical pivotal axis. 
     The supply of the flowable cooling medium from an external source of cooling medium to the storage tanks  118 ,  122  is effected through a cooling medium in-flow connector  126  which is arranged on the upper surface of the food transporting container  100  and incorporates a control valve  128  from where cooling medium in-flow lines  130  lead to each of the storage tanks  118  and  122 . 
     The removal of the flowable cooling medium to an external cooling-medium-sink is effected through a cooling medium return-flow connector  132  which is likewise arranged on the upper surface of the food transporting container  100  and incorporates a return valve  134  from where cooling medium return pipes  136  branch out to each of the storage tanks  118  and  122 . 
     Each of the vertical storage tanks  118 , of which one is illustrated in detail in  FIGS. 4 to 7 , is composed of a first side wall  138  (see  FIG. 4 ) that faces the interior of the respectively bordering holding chamber  120  and a second side wall  140  (see  FIGS. 5 and 6 ) that faces away from the interior of the respectively bordering holding chamber  120 . 
     The outer side of the first side wall  138  facing the interior of the respectively bordering holding chamber  120  is provided with horizontally extending beadings  142  which protrude into the holding chamber  120  and serve as support rails  144  upon which trays can be placed or upon which food containers and/or beverage containers can be placed directly. 
     The support rails  144  on the first side walls  138  of those vertical storage tanks  118  which respectively bound the same holding chamber  120  are arranged in pairs and are located opposite to each other at the same height level so that a tray or a food or a beverage container can be placed on this pair of support rails  144  in horizontal alignment. 
     The second side wall  140  of each vertical storage tank  118  is provided on the inner surface thereof facing the first side wall  138  with a plurality of horizontally extending strip-like projections  146  having a trapezoidal cross section (see  FIG. 7 ) the substantially vertically aligned front end faces  148  of which rest flatly against the inner surface of the first side wall  138  facing the second side wall  140 , wherein the first side wall  138  and the second side wall  140  are connected together in fluid-tight manner at the front end faces  148  of the second side wall  140  by a rolled seam welding process for example, so that the strip-like projections  146  of the second side wall  140  form partition walls  150  between each two storage tank segments  152  of the vertical storage tank  118  which are arranged vertically one above the other. 
     Each two storage tank segments  152  that are arranged one above the other are connected together by means of a connecting channel  154  which extends between an end region of the partition wall  150  between the two storage tank segments  152   a  and  152   b  on the one hand and a narrow-sided side wall  156  of the storage tank  118  ( FIG. 6 ). 
     As can best be seen from  FIG. 7 , the narrow-sided side walls  156  of the storage tank  118  are formed by folded portions  158  of the first side wall  138  which are connected in fluid-tight manner to likewise folded portions  160  of the second side wall  140  and in particular, are welded thereto. 
     Each of the connecting channels  154  is provided with a cooling medium guidance plate  162  made of sheet metal which comprises a lower section  164  at the height of the respective lower storage tank segment  152   a  and an upper section  166  at the height of the respective upper storage tank segment  152   b  ( FIG. 6 ). 
     In the exemplary embodiment illustrated here, the lower section  164  of each cooling medium sheet-metal guidance plate  162  comprises two inlet openings  168  for the cooling medium through which the cooling medium can enter the connecting channel  154  from the respective lower storage tank segment  152   a.    
     The top edge of the respective upper inlet opening  168   a  is spaced from the partition wall  150  separating the storage tank segments  152   a  and  152   b  from each other by a distance which corresponds at least approximately to a quarter of the height of a storage tank segment  152 . 
     After the vertical storage tank storage tank  118  has been filled with a multi-phase flowable cooling medium and in particular, with binary ice, and is decoupled from the external source of cooling medium and the external cooling medium sink, the multi-phase cooling medium begins to separate out and the lighter phase  174  (the ice phase in the case of binary ice) floats on the heavier phase  176  (on the liquid phase in the case of binary ice) in each of the storage tank segments  152 . 
     Since the lighter phase  174  (the ice phase for example) is thus disposed above the inlet openings  168  in each of the storage tank segments  152 , this lighter phase  174  does not enter the respective more highly located storage tank segment  152  through the connecting channels  154  in the storage operational mode of the storage tank  118 , so that the accumulations of the lighter phase  174  (the ice phase for example) remain distributed over the entire height of the vertical storage tank  118 , this being the reason as to why the vertical storage tank  118  and thus the first side wall  138  of the storage tank  118  forming a boundary wall of a holding chamber  120  remain uniformly cold over the entire height of the storage tank  118  in the storage operational mode of the storage tank  118 . 
     The upper section  166  of each cooling medium sheet-metal guidance plate  162  comprises a large outlet opening  170  in order to enable the cooling medium to exit from the connecting channel  154  into the respective upwardly located storage tank segment  152   b  in as unhindered a manner as possible. 
     Apart from the lowermost storage tank segment  152   d  and the uppermost storage tank segment  152   e  of a vertical storage tank  118 , all of the storage tank segments  152 , the storage tank segment  152   a  for example, are each connected by a respective first connecting channel  154   a  to a storage tank segment  152   b  located thereabove and by a second connecting channel  154   b  to a storage tank segment  152   c  located therebelow. 
     The first connecting channel  154   a  and the second connecting channel  154   b  are here arranged on mutually opposite sides of the storage tank  118  and are vertically displaced with respect to one another so that, when filling the storage tank  118  with fresh cooling medium, the cooling medium is caused to flow from bottom to top in meandering manner through the various storage tank segments  152  of the vertical storage tank  118  and the connecting channels  154  located therebetween. 
     The direction of flow of the cooling medium is indicated by the arrows  180  in  FIG. 6 . 
     The connecting channels  154  located vertically one above the other are separated from each other by means of a respective fluid-tight, horizontally directed bulkhead  172 . 
     The respective cooling medium in-flow line  130  associated with each storage tank  118  extends vertically downwards from the upper end of the storage tank  118  through these bulkheads  172  and ends within the lowermost storage tank segment  152   d.    
     The cooling medium return line  136  associated with the storage tank  118  extends downwardly from above into the interior of the uppermost storage tank segment  152   e.    
     For the purposes of filling the storage tank assembly  112  with fresh cooling medium which can absorb a large amount of latent heat, the food transporting container  100  is moved to a filling station where the cooling medium in-flow connector  126  is connected to a source of cooling medium in the filling station and the cooling medium return-flow connector  132  is connected to a cooling medium sink in the filling station. 
     After the control valve  128  and the return valve  134  have been opened, fresh cooling medium is pumped through the cooling medium in-flow lines  130  into the respective lowermost storage tank segments  152   d  by means of a pump in the external filling station so that the fresh cooling medium will displace the old cooling medium, which is present in the storage tank  118  and has already absorbed a large quantity of latent heat from the foods and beverages requiring cooling, from storage tank segment  152  to storage tank segment  152  in the upward direction and through the cooling medium return line  136  and the cooling medium return-flow connector  132  to the cooling medium sink in the filling station. 
     In order to achieve optimal exchange of the used and the new cooling medium when filling the storage tank  118 , the bulkheads  172  between the storage tank segments  152  are not absolutely fluid-tight.