Abstract:
A programmable cooking system including a plurality of programmable cooking devices and at least one data key. The, or each, data key is provided with a data memory for storing program data corresponding to sequences of cooking operations, and the data memory is divided into a plurality of parts each corresponding to a respective one of the cooking devices. Each programmable cooking device includes a programmable control means for controlling the cooking device to carry out sequences of cooking operations each of which may use a different cooking power and cooking time duration. Each programmable cooking device further includes a key aperture adapted to receive one of the data keys and a data reader arranged to read from the data key program data from that part of the data memory corresponding to the cooking device, and pass the program data to the programmable control means of the cooking device thus making the appropriate sequences of cooking operations available to the cooking device.

Description:
[0001]    This application claims priority to British Application No. 0022378.4, filed Sep. 13, 2000.  
         BACKGROUND OF THE INVENTION  
         [0002]    The invention relates to programmable cooking systems and methods of operating programmable cooking systems. The invention is particularly, although not exclusively, concerned with programmable cooking systems comprising one or more microwave or combination ovens.  
           [0003]    In the catering industry there is increasingly a need to be able to deliver a given range of meals from a menu at maximum speed and efficiency. In order to achieve this, it is common to use pre-programmed cooking devices, such as microwave ovens, which are loaded with program data representing an optimised cooking sequence for each item on the menu.  
           [0004]    For example, a combination oven (being an oven which can make use of a combination of microwave and conventional heating) may contain a cooking sequence for a given item on the menu which comprises three stages, namely a defrosting stage, a microwave cooking stage, and finally a browning stage using conventional heating.  
           [0005]    It will be appreciated that the cooking sequences must be carefully tailored to the particular oven being used, and the item to be cooked must match certain criteria (relating to the size and positioning of the food etc.) which are specified in advance. In order to avoid the need for the chef to manually program each cooking sequence into each oven, ovens are known which allow the chef to select each cooking sequence at the push of a button, or by entering a number corresponding to that cooking sequence.  
           [0006]    For example, an oven is made by Merrychef Ltd and sold under the name “Mealstream” which allows 10 different cooking sequences to be selected by simply pressing one of 10 different numbered buttons corresponding to the desired cooking sequence.  
           [0007]    However, a problem can arise when it is required to change a menu for a different menu, as may happen on different days during the week, or at different times during the same day. In addition it may be necessary to update menus to reflect items added or deleted from a given menu.  
           [0008]    In this regard it should be appreciated that the cooking sequences are usually determined at a different site (referred to herein as a data site) from the site at which the ovens are used (referred to herein as the cooking site), and there may be a number of cooking sites serviced by a single data site.  
           [0009]    In order to address this problem, it is known to update the program data for an oven using a modem connection to the oven, which allows data to be delivered from the data site to the cooking site. It is also known from U.S. Pat. No. 4,841,125 to use separate ROM modules which can be inserted into the oven in order to update the program data. Such ROM modules could for example be despatched by post from the data site to the cooking site.  
           [0010]    However, further problems can arise if the cooking site is relatively large and comprises an array of different cooking devices, such as microwave ovens, combination ovens, conventional ovens, steam combination ovens (using a combination of steam and conventional heating), and hobs. All of these cooking devices can be programmable, and all can be provided with program data representing a number of different cooking sequences corresponding to different items on a menu.  
           [0011]    Modem solutions can be costly because it is necessary to supply each cooking device with a modem. Furthermore, because the data is sent from a remote site, the chef may lose some control over exactly which updates are made and exactly when these updates are made.  
           [0012]    If ROM modules are used, the system can become complex to operate because it is necessary to supply a different module for each cooking device, and it is necessary for the chef to insert different modules into each cooking device each time it is required to change or update menus. As a result of this complexity errors can arise.  
         SUMMARY OF THE INVENTION  
         [0013]    The invention seeks to overcome at least some of the disadvantages of the prior art.  
           [0014]    According to the invention there is provided a programmable cooking system, and a method of operating such a system, as set out in the accompanying claims.  
           [0015]    It will be appreciated that because a single data key can be used with a number of different programmable cooking devices, the complexity involved in operating the system is reduced. The system is thus easier for the chef to use, and the likelihood of mistakes being made during the operation of the system is reduced. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:  
         [0017]    [0017]FIG. 1 shows a data key and key aperture for use with the embodiments described;  
         [0018]    [0018]FIG. 2 shows a microwave combination oven provided with such a key aperture;  
         [0019]    [0019]FIG. 3 is a schematic diagram showing the arrangement of components of the microwave combination oven;  
         [0020]    [0020]FIG. 4 shows the arrangement of blocks of memory on the data key;  
         [0021]    [0021]FIG. 5 shows the sequence of operations carried out in a first embodiment;  
         [0022]    [0022]FIG. 6 shows the sequence of operations carried out in a second embodiment; and  
         [0023]    [0023]FIG. 7 shows the steps carried out in a method of operating a programmable cooking system in accordance with an embodiment of the invention.  
     
    
     DETAILED DESCRIPTION  
       [0024]    [0024]FIG. 1 shows a data key  1  (for example Serial Memory Token LCK 16000 manufactured by Datakey, Inc. of 407 West Travellers Trail, Burnsville, Minn. 55337, USA) and a data key reader  2 . The reader  2  is provided with a key aperture  2   a  adapted to receive the key  1  in order to allow data to be passed to and from the key  1 . The key  1  is provided with E 2 PROM (electrically erasable programmable ROM) for storing data, and with a number of electrical contacts  1  a for communicating with the reader  2 .  
         [0025]    [0025]FIG. 2 shows the key reader  2  mounted in the front panel of a microwave combination oven  5  (for example model EV2451 made and sold by Merrychef Ltd). The oven  5  is provided with a manual control panel  4 , door  6 , and twenty pre-program keys  3  which allow twenty pre-programmed cooking sequences to be called up at the touch of a button.  
         [0026]    [0026]FIG. 3 shows the electronic components of the oven  5 , being the key reader  2 , preprogram keys  3 , manual control panel  4 , together with a display  7 , CPU (central  2  processing unit)  8 , switching unit  9 , alarm/beeper  10 , E 2 PROM  11 , fan  12 , heater  13 , and magnetron  14 . The E 2 PROM  11  exchanges data with the data key  1  via the CPU  8  in known manner.  
         [0027]    The data key  1  is provided with program data corresponding to different cooking sequences at a data site, and is then sent to the cooking site for use with the oven  5 , and with other programmable cooking devices (not shown), each of which is provided with a key reader  2 . Although only the oven  5  is described here, the data key  1  operates with each other programmable cooking device in similar fashion.  
         [0028]    [0028]FIG. 4 shows a typical arrangement of the memory of the data key  1 . The memory is divided into 5 blocks, B 1  to B 5 , each of which contains data corresponding to the cooking sequences of a different type of cooking device. Thus, in the example the blocks B 1  to B 5  correspond to a microwave combination oven, a microwave oven, a conventional convection oven, a steam combination oven, and a hob respectively.  
         [0029]    In the example of FIG. 4, each block contains three programs, P 1  to P 3 , each containing the data for a different cooking sequence comprising a number of stages S 1 , S 2 , S 3  etc. Each stage contains data specifying the time, power and temperature (or other controllable features) for that stage of the cooking sequence.  
         [0030]    The data key  1  can be inserted into any or all of the available cooking devices in order to update the program data for that cooking device. In the example of FIG. 4 the key  1  works with any cooking device of the type corresponding to a given block of the key memory. However, further embodiments are possible in which different blocks are provided for different cooking devices of the same type. For example, a given cooking site may have a number of microwave ovens of the same type which require different program data.  
         [0031]    [0031]FIG. 5 shows the sequence of operations carried out by the oven  5 .  
         [0032]    In step  20  the oven  5  is turned on. In step  22  the oven  5  checks whether a key is present in the key reader  2 . If a key is present, at step  24  the oven  5  locates the memory address for the relevant block B 1  of memory on the data key  1  corresponding to cooking devices of the type of oven  5 .  
         [0033]    At step  26  the contents of block BI are downloaded from the data key  1  to the E 2 PROM  11  of oven  5 .  
         [0034]    At step  28  diagnostic and operational data is uploaded from the oven  5  to the data key  1 . This data is then available for analysis when the data key  1  is returned to the data site at which the data key  1  was initially programmed, or to a separate analysis site. The operational data can be any data relating to the oven  5  and/or the way in which the oven  5  has been used. For example, the operational data may include the number of times each cooking sequence has been performed by the oven  5 , the total time for which the oven  5  has been used, the times at which the oven  5  has been used, and so on.  
         [0035]    Operational data can be uploaded to the data key  1  from each different programmable cooking device, and stored in different parts of the memory on the data key  1 .  
         [0036]    Each data key  1  can be assigned a different key number, and in step  30  the key number, which is read from the data key  1  by the key reader  2 , is displayed on the display  7 . For example, there may be different keys for different days of the week, or for different times of day, and the display of the key number therefore allows the chef to confirm that the correct key has been inserted. The keys can be physically connected together, for example on a single ring, and can also be colour coded using different colours to assist with the correct identification of each key.  
         [0037]    If no key is present at step  22 , the display  7  displays the key number of the last data key  1  to have been inserted into key reader  2 . This confirms to the user which cooking sequences are currently stored by the oven  5 .  
         [0038]    In step  32  the data key  1  is removed from the key reader  2 , and in step  34  the oven  5  determines whether the user has selected to operate the oven  5  in a manual, or preprogrammed mode. If the manual mode is selected, the oven  5  does not make use of the program data downloaded from the data key  1 , and is simply operated using the manual control panel  4  in normal fashion.  
         [0039]    If the user has selected the pre-program mode, then at step  36  the user enters the appropriate program number using pre-program keys  3 , and at step  38  the oven  5  then retrieves the program data corresponding to the appropriate cooking sequence from the E 2 PROM  11  and cooks the food at step  40 .  
         [0040]    [0040]FIG. 6 shows the sequence of operations carried out by an alternative embodiment of oven  5 . Steps corresponding to those in FIG. 5 are given the same reference numerals. However, in the embodiment of FIG. 6 the data key  1  is not removed from the oven  5  during operation, and at step  42  the program data is retrieved directly from the data key  1 , rather than from the E 2  PROM  11  of the oven  5 . In this embodiment use of the pre-programmed cooking sequences is only available while the data key  1  remains in the key reader  2 .  
         [0041]    In a further embodiment of the invention, the oven  5  is programmed so that it cannot be operated at all unless a data key is present in the key reader  2 . This provides a useful security feature which has applications in various areas, including hospitals, schools and institutions where unauthorised use of the oven  5  could be hazardous.  
         [0042]    [0042]FIG. 7 illustrates one embodiment of a method of operating a cooking system of the type described above. In FIG. 7 it is assumed that Merrychef Limited (denoted MC) acts as the data site and analysis site for a number of cooking sites.  
         [0043]    At step  50  MC is advised that a new menu is required. MC then, at step  52  determines optimum cooking sequences or programmes for each item or dish on the menu. This requires experiments to be conducted with the various items on the menu in order to determine the optimum times, temperatures and powers for each stage in the cooking sequence for each dish. These experiments are conducted for a number of different programmable cooking devices, for example the cooking devices listed in FIG. 4.  
         [0044]    At step  54  program data corresponding to the cooking sequences is entered on to a computer according to the format shown in FIG. 4.  
         [0045]    At step  56  the program data is downloaded to a number of differently coloured data keys, the data on each key being arranged in the format of FIG. 4. It is assumed that the menu specifies that different dishes will be available on different days and at different times of day, and each key corresponds to a different time and has program data downloaded to it accordingly.  
         [0046]    At step  58  the data keys are sent, for example, by post, from MC to each customer cooking site.  
         [0047]    At step  60 , the site manager or chef at each cooking site inserts the data keys into key readers of the programmable cooking devices at the appropriate times.  
         [0048]    At step  62  data is downloaded from the data keys and uploaded to the data keys in the manner described above.  
         [0049]    At step  64  each key is returned to MC, and at step  66  the uploaded data is analysed and stored by MC. The uploaded operational data can be used to determine how many meals of each type have been cooked, and this data can be used for stock control and stock ordering purposes. The uploaded operational data can also indicate how long each cooking device has been used for. If the cooking devices are supplied by MC under warranty, such data can be used to determine whether or not the cooking devices fall within the terms of the warranty. For example, a warranty may specify that a cooking device only remains under warranty if its usage, or usage within a given period of time, falls below a certain number of hours. The operational data can also be used in a variety of other ways. For example, it sometimes happens that the cooking device which is located nearest to a given chef or cook is over-used relative to another cooking device of the same type at the cooking site. The operational data can be used to determine and correct such patterns of use.  
         [0050]    Step  68  indicates that different coloured data keys are used for the next menu for which MC prepares data keys.