Patent Publication Number: US-2007119195-A1

Title: Cooling appliance

Description:
The invention relates to a refrigerator with a goods space for industrially produced frozen goods.  
      Ice cubes consist of frozen water and are required, as a rule, in the catering trade and in the private area. Ice cubes are used in particular for preparing or cooling cocktails and other cold drinks. Furthermore, they can be used for cooling cold dishes, for example for large buffets. In addition to ice cubes, chopped ice cubes, so-called “crushed ice”, are also increasingly used for the preparation of cocktails. To produce ice cubes, water can be frozen in a deep-freezer in ice-cube molds or else in bags with a number of honeycombs. Furthermore, there are refrigerators and deep-freezers which produce ice cubes automatically and store them in a container ready for withdrawal.  
      In the catering trade, for large-scale events or also for large-scale private celebrations, where large quantities of ice cubes are needed, it is as a rule not feasible and too expensive to produce ice cubes by oneself, so that for these purposes industrially produced ice cubes are usually purchased. Industrially produced ice cubes and also industrial crushed ice is usually filled by weight and packed in plastic bags, stored in refrigerators and offered for sale. Refrigerators for the sale of ice cubes, for example freezers, freezer chests or deep-freezer chests, are usually installed in wholesale markets, supermarket and also in service stations.  
      In addition to water, the production of ice cubes requires large quantities of electrical energy, so that industrially produced ice cubes are produced centrally. For this purpose, large freezing machines can be used, whereby, on the one hand, energy costs can be minimized and, on the other hand, only few freezing machines have to be installed and manufactured, so that investment costs can also be kept low.  
      It is, however, a disadvantage of the central production that the ice cubes have to be transported to the customers or to the installed refrigerators, which constitutes considerable expenses for supplying the ice cubes. This is in particular due to the fact that the central production disproportionately increases the production costs, consisting of the fixed costs and the variable unit costs for water and energy, which are relatively low in comparison with the fixed costs. In view of the transportation costs, the variable unit costs are disproportionately increased, due to the specific characteristics of the ice cubes.  
      In addition, the demand for ice cubes and crushed ice is strongly cyclical, so that it is difficult to forecast when a refrigerator will have to be refilled. The reason for the cyclic demand is on the one hand a dependency on the weekday or on the weather, as on warmer days clearly more ice cubes are purchased, and on the other hand large-scale events unforeseeable for the producer, for which unexpectedly large quantities of ice cubes are purchased. To avoid that the ice cubes of certain refrigerators are completely sold out, it is, however, not possible to increase the size of the refrigerators to an unlimited extent as this would increase the energy costs for the operation of the refrigerators and also the rent for the floor space of the refrigerators.  
      Therefore, one tries, when supplying the refrigerators, to forecast the level of the refrigerator in question in order to determine an appropriate refilling date. It is a disadvantage of this procedure usual in practice that due to the above-described problem of cyclic demand, the ice cubes of refrigerators are sold out, or that the producer unnecessarily makes a refilling call at a sufficiently filled refrigerator. This causes loss of turnover and unnecessary transportation costs.  
      Therefore, it is the object of the invention to provide a refrigerator with a goods space for industrially produced frozen goods, which can be supplied with new goods as efficiently as possible.  
      This object is achieved according to the invention by the fact that the goods space of the refrigerators is provided with a level sensor.  
      The invention is based on the consideration that for an efficient refilling of a number of refrigerators, the planning of the refilling itinerary should be optimized. For this purpose, the quantity of frozen goods contained in the goods space of a refrigerator should be known and should, therefore, be determined or measured. It can then be decided by means of the filling level whether or not a refrigerator has to be supplied with new goods. Furthermore, the moment when a refilling is necessary can be forecast better. Therefore, to measure the level of a refrigerator, the latter&#39;s goods space is provided with a level sensor.  
      To determine the level of frozen goods in the goods space independently of the type of storage or the stacking of the individual frozen products, the level sensor is advantageously a balance. The balance can be appropriately positioned as a function of type and way of loading of the refrigerator, so that a particularly reliable measurement of the weight of the goods contained in the refrigerator is possible. By means of the measured weight of the frozen goods and the known weight of the individual frozen products, their number or another characteristic value for the level can be determined.  
      To measure the weight, the balance is expediently provided with a strain gauge, which is in a position to record a movement caused by the mass of the frozen goods, for example the movement of the bottom of the goods space, thus determining the weight of the frozen goods.  
      In an alternative or additional advantageous embodiment, the level sensor comprises a so-called RFID sensor system. Preferably, a transmitter, for example an RF transmitter, is provided inside the goods space, emitting a characteristic signal for inquiring the level. In such a system, the goods packages are provided with suitable chips, in the manner of a code, which passively reflect a reply signal in response to the emitted signal, which, in turn, can be received by the transmitter and receiver unit. In the manner of a code, the chips can be designed in an individualized manner in such a way that a characteristic reply signal is generated which depends, for example, on type, best-before date or other parameters of the goods in question. Through evaluation of these signals, it is possible to also determine, in addition to the global level, the composition of the goods contained in the goods space, in the manner of a qualified level measurement, so that a refilling which is particularly well adapted to the requirements can be arranged for. This is particularly advantageous when loading the refrigerator with different kinds of goods, for example with both ice cubes and crushed ice or with different kinds of ice cream.  
      To enquire the level of a refrigerator or send it to a central evaluation unit, the level sensor is preferably connected with a data-transfer unit.  
      To transmit the levels, a plurality of decentral refrigerators of a goods management system for industrially produced frozen goods are advantageously connected, concerning their data, by means of a data-transfer unit with a central evaluation unit. A data-transfer unit can be designed, according to availability and costs, for wireless or wire-bound communication. One can choose for this purpose, for example, mobile communication (GSM, GPRS, UMTS), wireless communication, wire-bound communication, WLAN, the Internet or a connection over the mains supply (“Powerline”). A communication as an IP connection is particularly advantageous because the protocols used in this case are suitable for almost all hardware types in the evaluation.  
      During the operation of such a goods management system, the level of the respective refrigerator is expediently transmitted by a data-transfer unit to the evaluation unit. A transmission and subsequent evaluation of the levels can be effected, for example, continuously, according to a cyclic monitoring. Alternatively, however, the levels can be stored intermediately and transmitted and evaluated at relatively long time intervals, according to a logging.  
      To allocate in the central evaluation unit a transmitted level to a certain refrigerator, preferably an individual code of a refrigerator is included in the transmission. In addition, the time of the level measurement and other parameters like, for example, temperature values, can be transmitted.  
      The transmission can be effected at specified intervals. Alternatively, it is possible to transmit the level to the central evaluation unit only when needed, i.e. when the level of a refrigerator falls below a maximum minimum level. For this purpose, a level of a refrigerator is advantageously stored in a data memory of a refrigerator.  
      To make it possible to inquire the level of a refrigerator also by the central evaluation unit from the data memory, the transmission process has expediently a bidirectional design. Upon the inquiry, a command for a new level measurement of a refrigerator and its transmission to the central evaluation unit can be transmitted.  
      For a simple determination of the level and for the sake of clarity of the transmitted data of the level, a current level of a refrigerator is expediently not transmitted after each withdrawal of goods. Rather is a measured level preferably transmitted in the form of predefined level categories. Rather is the level rounded to the predefined level categories. For this purpose, the level categories are adapted to the size of a refrigerator, so that, for the supply with new goods, the quantity of these goods can be determined by means of the categories and the size of a refrigerator. In particular, categories like “completely filled”, “filled more than half”, “filled more than one quarter”, “filled less than one quarter” can be provided.  
      To record the withdrawal and refilling process of the frozen goods in real time, as far as possible, a level should advantageously be transmitted whenever it reaches a new level category.  
      The advantages achieved with the invention consist in particular in the fact that by measuring the levels of refrigerators and transmitting them to a central evaluation unit, the exact requirements of new goods are known and can, furthermore, also be forecast with greater accuracy. For example, the problem of the cyclic demand for frozen goods can be mitigated by immediately detecting a dynamically increasing demand and arranging for the supply of new goods.  
      By means of the determined levels, the supply can be adapted to these requirements and the supply and logistic processes can be optimized by supplying a plurality of refrigerators by means of an itinerary planning adapted to the requirements.  
      In this way, considerable costs can be saved by maximizing the capacity of the supply vehicles, omitting calls at refrigerators which are still full, and minimizing the number of calls at refrigerators, as the refrigerators will only be refilled shortly before the goods are sold out. Furthermore, the invention can reduce losses in turnover, which previously occurred due to the fact that goods of refrigerators were sold out.  
      Another advantage of the invention is the possibility to elaborate customer profiles by means of the level measurements and to utilize them for economic purposes. 
    
    
      In the following, an exemplary embodiment of the invention is explained in detail by means of a drawing, in which  
       FIG. 1  is a diagram of a goods management system for ice cubes,  
       FIG. 2  is a sectional view of a refrigerator for ice cubes of a goods management system according to  FIG. 1 , and  
       FIG. 3  shows an alternative refrigerator for the goods management system according to  FIG. 1 . 
    
    
      In all figures, identical parts are marked with the same reference numbers.  
       FIG. 1  is a diagram of a goods management system  2  for industrially produced ice cubes and/or so-called crushed ice with a number of refrigerators  1 . The refrigerators  1  are installed, decentralized, in various supermarkets, shops and service stations. To supply the refrigerators  1  with ice products as efficiently and cost-advantageously as possible, the goods management system  2  and the refrigerators  1  are designed for individual determination of the requirements of new goods for each individual refrigerator  1 . For this purpose, each refrigerator  1  is provided with a level sensor, by means of which the level of the refrigerator  1  can be determined. To illustrate this more clearly,  FIG. 2  shows a refrigerator  1  of a goods management system  2 .  
      The refrigerator  1  could, for example, be a freezer. In the exemplary embodiment, however, the refrigerator  1  is a freezer chest, in particular a deep-freezer chest. The frozen goods are stored in a goods space  4  surrounded by an outer wall, ice cubes packed in bags being in particular provided. The body of the freezer chest surrounding the goods space  4  is carried on four bases  5 . In each of these bases, a weighing cell with a strain gauge  8  is integrated to form a balance  6 , so that by recording the local load of the bases and taking into account characteristic parameters of the freezer chest, like, for example, its own weight, the weight of the ice cubes can be determined. By means of this weight, the level in the goods space can be determined, so that the balance  6  services as a level sensor. Alternatively, the weight can also be determined or the level can be measured, for example, by a weight sensor, a temperature sensor, a volume sensor, an ultrasonic sensor, a motion detector, a pressure sensor, a light barrier, a radar, a sonar or a laser for depth measurement.  
      Using the weight of the ice cubes as an input quantity, the microcontroller  16  computes and monitors the level of the available ice-cube bags. The level can be recorded and evaluated in the manner of a continuous parameter. In the exemplary embodiment it is, however, provided, for a particularly simple processing requiring only little processing capacity, to subdivide the level for the sake of more clarity into a number of (in the exemplary embodiment, four) measuring limits: full load, ¾ load, ½ load, and ¼ load. When any of these measuring limits is reached, a message including date stamp, hour and a refrigerator identification code will be transmitted by a data-transfer unit  18  to the evaluation unit  3 . In addition, the level will be stored in a data memory  20  and can be inquired, if necessary, by the evaluation unit  3  via the data-transfer unit  18 .  
      For this purpose, the transmission method is of bidirectional design, the refrigerator  1  being connected in the exemplary embodiment via the data-transfer unit  18  with the Internet with der evaluation unit  3 . Alternatively, other transmission methods, such as, for example, transmission over the mains supply, by WLAN, wireless communication, mobile communication (GSM, GPRS, UMTS) or over a separate transmission line are also imaginable.  
      If after seven days, no data transfer has taken place, the microcontroller  16  will automatically send a test signal to the evaluation unit  3 .  
      The program of the microcontroller  16  is designed in such a way that it can be adapted to an individual size of a refrigerator  1 , without requiring any programming knowledge. The parameters of the refrigerator  1 , such as size, empty weight and load, are entered for this purpose by means of a keypad  22  provided on the refrigerator  1  or else in the manner of remote initialization, over the evaluation unit  3 . Upon first putting into service, the program will be imported by means of a computer over a serial interface, which is not shown in detail in the drawing. The refrigerator identification code can be assigned to the refrigerator  1  either over the keypad  22  or alternatively, over an interface.  
      An alternative embodiment of a refrigerator  1 ′ is shown in  FIG. 3 . Regarding many components, for example for the processing, storing and/or transmission of data, the refrigerator  1 ′ is essentially of identical construction as the refrigerator  1 . It differs, however, by the level-measuring system provided in that case, as the refrigerator  1 ′ comprises a so-called RFID sensor system  28  as a level sensor. Inside the goods space  4 , a sender and receiver unit  30 , in the exemplary embodiment, an RF sender, is arranged. To inquire the level, the sender and receiver unit  30  emits a characteristic signal, which is reflected by chips  34  integrated into the goods packages  32  of the goods contained in the goods space  4 , the chips  34  being configured in such a way that the signal reflected by them has individual, chip-specific properties, in the manner of a characteristic signature.  
      Thus, by means of suitable coding and evaluation of these reflected signals, information which is characteristic of the respective goods package  32 , such as, for example, kind of goods, quantity unit, best-before date or the like can also be transmitted. Responding passively to the emitted signal, the chips  34  thus reflect a reply signal, which, in turn, can be received by the sender and receiver unit  30 . Through evaluation of these signals, it is, therefore, possible to also determine, in addition to the global level, the composition of the goods contained in the goods space, in the manner of a qualified level measurement, so that a refilling which is particularly well adapted to the requirements can be arranged for. This is particularly advantageous when loading the refrigerator with different kinds of goods, for example with both ice cubes and crushed ice or with different kinds of ice cream.  
     LIST OF REFERENCE NUMBERS  
     
         
           1  Refrigerator  
           2  Goods management system  
           3  Evaluation unit  
           4  Goods space  
           5  Base  
           6  Balance  
           8  Strain gauge  
           16  Microcontroller  
           18  Data-transfer unit  
           20  Data memory  
           22  Keypad  
           28  Sensor system  
           30  Sender and receiver unit  
           32  Goods package  
           33  Chip