Abstract:
The invention relates to a device for heating food comprising a frame, a pan or basket having an opening into which the food to be heated can be placed, which pan or basket can be coupled to the frame by means of coupling means and in which the frame comprises a heating element and a fan for circulating heated air in the pan or basket, and a drive for rotating the pan or basket about a non-vertical rotation axis during the heating of food in a heating position of the frame. The frame is designed such that the pan or basket can be coupled to the frame while the pan or basket is on a supporting surface with its opening directed upwards. The invention also comprises a method for heating food.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to a device for heating food. A device of this type is known from WO 0124673, Hoebrigs. The drawback of the known device is that the pan or basket has to be filled with food through a small opening with the pan or basket being installed inside the device, which is awkward. 
       SUMMARY OF THE INVENTION 
       [0002]    In order to overcome this disadvantage, the device is designed in that the frame is designed so that the pan or basket can be coupled to the frame of the device while the pan or basket is on a supporting surface and has its opening directed upward. As a result, the pan or basket can be filled in a simple manner while preventing the problem of food falling outside the pan or basket during filling. 
         [0003]    In accordance with an improvement, the device is designed with supporting feet. As a result, it is readily possible to couple the pan or basket to the frame and keep it in the heating position during heating. 
         [0004]    In accordance with an improvement, the device is designed with a frame that is tiltably connected to a baseplate. This ensures a stable arrangement of the device on a supporting surface. 
         [0005]    In accordance with an improvement, the device is designed with a spring arranged between the frame and a baseplate. This ensures that little force is required to tilt the pan or basket to assume the heating position. 
         [0006]    In accordance with an improvement, the device is designed with a sensor for detecting when the frame is in the heating position. As a result, the operation of the device is made dependent on the position of the frame, making it possible, for example, to make safeguards dependent on this position. 
         [0007]    In accordance with a further improvement, the device is designed with a switch for switching on the drives, fan or heating element with a sensor connected to the switch. As a result, switching on the drive, the heater and/or the fan can be made dependent on the position of the frame, as a result of which mistakes during use and thus potentially dangerous situations are avoided. 
         [0008]    In accordance with an improvement, the device is designed with resilient couplers for clamping the pan or basket against the frame. This ensures that the pan or basket can be coupled to the frame in a simple manner. 
         [0009]    In accordance with a further improvement, the device is designed with resilient couplers that can be moved simultaneously into an uncoupled position by displacing a common ring. This ensures that the pan or basket can be uncoupled from the frame in a simple manner. 
         [0010]    In accordance with a further improvement, the device is designed with couplers having a beveled edge. This ensures that the pan or basket can be coupled to the lid by placing the frame with the lid over the pan or basket and pressing the lid onto the pan or basket. 
         [0011]    In accordance with an improvement, the device is designed with a coupler that can rotate in a bearing and a flexible ring is provided between the bearing and the coupler. This ensures that the thermal expansion resulting from the heating does not influence the play in the bearing. 
         [0012]    In accordance with an improvement, the device is designed with the fan and heating element provided on a holder and the coupling means rotate with respect to the holder. This ensures that the fan and/or heating element have an approximately stationary position relative to the frame, as a result of which the power supply can be effected in a simple manner via a power lead. 
         [0013]    In accordance with a further improvement, the device is designed with the motor mounted on the holder. This ensures that the motor can drive the fan directly, which is easier and leads to fewer failures in transmission belts and the like. 
         [0014]    In accordance with an improvement, the device is designed with a pan made of heat resistant glass. This ensures that a pan is available which is easy to clean. 
         [0015]    In accordance with a further improvement, the device is designed with a pan having a reflective layer. This ensures that better use is made of the radiation for browning and/or cooking the food. 
         [0016]    In accordance with a further improvement, the device is designed with a pan having indentations. This ensures that the pan is easy to handle and prevents the food from simply sliding, as it is forced to roll over indentations. 
         [0017]    In accordance with an improvement, the device is designed with a pan or basket having partitions. This ensures that various kinds of foods can be heated simultaneously. 
         [0018]    In accordance with an improvement, the device is designed with the frame coupled to a manipulator for automatically coupling or uncoupling the pan or basket and tilting frame. This ensures that the food can be heated automatically, the device, for example, forming part of a machine for heating food automatically. 
         [0019]    The invention also comprises a method. By means of this method, the pan or basket can be filled in a simple manner, the food, after the tilting as a result of the rotation of the food, being able to move and roll along the side wall of the pan or basket. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0020]    The invention will be explained below with reference to a number of exemplary embodiments with the aid of a drawing, in which: 
           [0021]      FIG. 1  shows a diagrammatic cross section through a first exemplary embodiment of a heating device for food; 
           [0022]      FIG. 2  shows a diagrammatic plan view of the device of  FIG. 1  with a partially cut-away cover and a detail of the drive; 
           [0023]      FIG. 3  shows a diagrammatic side view and a partial cross section of the device from  FIG. 1 , and 
           [0024]      FIG. 4  shows a diagrammatic side view of a second exemplary embodiment of a heating device for food. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    The heating device shown in  FIGS. 1 ,  2  and  3  comprises a lid  21  which can be coupled to a pan  18 . The lid  21  is rotatably mounted in a cover  5  and is provided to this end at its circumference with a bearing ring  16  which can rotate in the cover  5  about a rotation axis  19  and which is positioned inside the cover  5  in the axial direction by, inter alia, an edge  17 . The edge  17  protects the underside of the lid  21 , preventing a user from accidentally touching the hot parts of the lid  21 . 
         [0026]    Six springs  30  are provided on the lid  21  for coupling the pan  18  to the lid  21 , which springs are provided, at their loose ends with a hook  29  which can grip around an upper edge of the pan  18  (in  FIG. 1 , the springs  30  on the left-hand side of the figure have been drawn in a position which is rotated about thirty degrees for the sake of clarity). As the lid  21  is pressed onto the pan  18 , the upper edge of the pan  18  presses the hooks aside until these hooks  29  fall around the upper edge and grip the pan  18  securely in such a manner that the pan  18  and the lid  21  are coupled. A resilient ring  20  is placed between the pan  18  and the lid  21  as a seal. This resilient ring  20  and the springs  30  are designed such that the hooks  29  can engage with the upper edge when the ring  20  is pressed, following which the ring  20  presses the upper edge downward in such a manner that the latter is pressed down against the hook  29 . 
         [0027]    On that side of the lid  21  which faces the pan  18 , a coiled heating element  23  is arranged, as well as a fan  24 . The fan  24  is attached to a shaft  25  of a motor  7 . A grid  22  is arranged on the underside of the lid  21  on order to protect the heating element  23  and the fan  24 . This grid  22  preferably consists of small-meshed gauze made of thin metal wire, so that a good permeability is ensured for the infra-red radiation emanating from the heating element  23 . The grid  22  can be detached from the lid  21  for ease of cleaning. 
         [0028]    In the embodiment shown, the lid  21  is made of metal, but it is likewise possible to use other materials. During switching on of the heating element  23  the lid  21  heats up, resulting in an increase in its diameter. An expansion rim  15  is provided between the part of the lid  21  which becomes hot and the bearing ring  16  which can absorb the increase in diameter of the heated part of the lid  21  so that the bearing play between the bearing ring  16  and the cover  5  does not become too small. 
         [0029]    Before the pan  18  can be detached from the lid  21 , the six hooks  29  have to be moved outwards simultaneously. In order to achieve this, a ring  14  rests on the springs  30 , the springs  30  being shaped in such a manner that the hooks  29  move outwards when the ring  14  is pressed downwards. The springs  30  and the ring  14  rotate with the lid  21 . The ring  14  has a flat top surface which moves under push-buttons  1  when the lid  21  rotates. By means of the push-buttons  1 , the ring  14  can be pushed down as a result of which the hooks  29  move outwards and the pan  18  is detached from the lid  21  and the lid  21 , together with the cover  5  can be lifted off the pan  18 . The push-buttons  1  are pushed upwards by the springs  30  and the ring  14 . The upward movement of the push-button  1  in the cover  5  is limited by a pin  2 . Handles  33  are arranged in the cover  5  for easy operation of the push-buttons  1 . 
         [0030]    The motor  7  can rotate with respect to the lid  21 , for which purpose a bearing ring  26  is incorporated in the lid  21 , enabling this rotation. The motor  7  is clamped inside a holder  8  by means of a clamp  34 . The holder  8  is coupled to the cover  5  by supports  4 . The heating element  23  is fastened to the underside of the motor  7  and a supply lead  10  for the heating element  23  runs to a switch  13  via the underside of the motor  7 . A supply lead  9  for the motor  7  also runs to the switch  13 . The motor  7  is also used for rotating the lid  21  inside the cover  5 . To this end, a pulley  6  is arranged on the shaft  25  at the top of the motor  7 . A drive belt  3  is tensioned around the pulley  6  and also runs around a disc  36 . The disc  36  is mounted on a shaft  31  which can rotate at the top in a bearing (not shown) mounted in the cover  5 . At its bottom, the shaft  31  is provided with a drive roll  37  which is pressed against the bearing ring  16  by a spring  32 . By selecting the diameters of the pulley  6 , the disc  36  and the drive roll  37 , the speed of rotation of the lid  12  and thus of the pan  18  can be selected. 
         [0031]    The cover  5  is provided with two supports  28  which are dimensioned such that there is a distance a between the supports and a table when the rotation axis  19  is vertical and the pan  18  is on the table and clamped securely by the hooks  29 . After tilting, when a rotation axis  19  of the pan  18  is horizontal, the supports  28  rest on the table by means of a support plate  27  and a support plate  38  and the pan  18  can rotate freely. In order to facilitate the tilting, a handle  35  is provided on the cover  5 . It will be clear that it is also possible to have embodiments where the supports  28  and the support plates  27  and  38  are designed in such a manner that the rotation axis  18  is not at an angle of ninety degrees to the vertical when the support plates  27  and  38  rest on the table, but are at another angle, different from zero. 
         [0032]    A sensor  11  is arranged in the cover  5  for detecting this tilted position in which the pan  18  can rotate freely. When the sensor  11  detects the tilted position, the heating element  23 , the fan  24  and thus the rotational drive of the pan  18  can be switched on. 
         [0033]    In use, the pan  18  described above is filled with food to be heated, coupled to the lid  21 , and subsequently the pan  18  is tilted. Then, the heating element  23 , the fan  24  and the drive of the lid  21  are switched on and the food is heated. After a few minutes, when the food is cooked, the heating element  23 , the fan  24  and the drive of the lid  21  are switched off, the pan  18  is put on the table. Subsequently, the push-buttons  1  are pushed in, as a result of which the hooks  29  move outwards and the cover  5  can be lifted from the pan  18 . The heated food can then be taken out of the pan  18 . 
         [0034]    It has been assumed in the embodiment shown that the pan  18  rotates continuously in the same direction. In a situation where the direction of rotation of the pan  18  vary and the rotation in one direction is in each case limited, the motor  7  can be securely mounted in the lid  21 , while the supply leads  9  and  10  can run directly to the motor. In this case, however, a sensor and/or switch in order to limit the rotation is required. One possible embodiment may feature a reverse clutch between a motor and the pan  18 , the sensor switching the reverse clutch and thereby reversing the rotational direction of the pan  18 . Optionally, the drive for the pan  18  and the fan  24  are designed as separate units and there are two motors which can be operated independently. As a result, the use of the pulley  6 , the disc  36  and the drive belt  3  is redundant, resulting in fewer failures. 
         [0035]    The pan  18  may have a diameter of between 20 and 60 cm and a depth of 15 to 30 cm. The speed of rotation of the pan  18  is approximately 10 revolutions per minute, if desired between 5 and 15 revolutions per minute. Optionally, the supports  28  of the device are designed such that, during the heating, the pan rotates about an axis which is at an angle to the horizontal plane, for example an angle of thirty degrees, so that the food partially rests against the side wall and on the bottom of the pan  18  during heating. 
         [0036]    The pan  18  may be made of heat-resistant glass. The surface of the glass is preferably metallized or the glass is made to be reflective in another way, so that the infra-red radiation from the heating element  23  reflects on the pan  18  and further heats the food present in the pan  18 . Other embodiments are likewise possible, such as a metal pan or also a basket. In one embodiment, the pan  18  or basket, respectively, may be provided with partitions, which may be removable, if desired. In that case, different kinds of food are placed in the various compartments of the pan  18 , which can be heated separately. Indentations  12  may be provided in order to be able to pick up the pan easily. These indentations may also be useful for moving the food in the pan  18 , as these indentations interrupt any possible sliding of the food, so that it starts to “roll” and is better heated on all sides. 
         [0037]    In the embodiment shown, a simple switch  13  is shown for operating the device. Obviously, the device may also be provided with features which prevent overheating of the heating element  23  and it is also possible to design the device to have a programmable controller, a timer and other features known for the use of the device in the preparation of meals. 
         [0038]    It will be clear to those skilled in the art, that the abovementioned cover  5  may be moved by a manipulator which, for example, forms part of a machine for heating food, rather than by a cook. Once the food has been place in the pan  18 , if desired automatically, the cover  5  and the pan  18  are coupled by the manipulator and subsequently also tilted. 
         [0039]    After heating, the pan  18  and the cover  5  are uncoupled by displacing the ring  14  using a drive fitted into the cover  5  for this purpose. The pan  18  is removed and automatically emptied, if desired, into a small tray which can be taken out of the machine. The machine may be provided with a payment system with selection means, so that an individual may, after payment, have a portion of food heated in the machine, with the machine carrying out the heating in the manner described above. 
         [0040]      FIG. 4  shows a second embodiment of the heating device, in which most components are more or less identical to the components of the first exemplary embodiment. In the second embodiment, the cover  5  is pivotably attached between two supporting legs  43  by means of, inter alia, a hinge  40 . The supporting legs  43  are attached to a baseplate  45  which may be placed on a worktop, for example. A fastening eye  41  is fixed to the cover  5  and a fastening eye  44  is fixed to the baseplate  45 . A spring  42  is arranged between the fastening eyes  41  and  44 , which spring is designed such that the cover  5  with all the components attached to it, and the pan  18  are tilted upwards by the effect of the spring force of the spring  42 , in such a manner that the rotation axis  19  of the pan is at an angle with the vertical, as indicated in  FIG. 4 . Positioning projections  46  are fitted on the baseplate  45  into which the pan  18 ′, indicated in  FIG. 4  by a broken line, can be placed. 
         [0041]    When using the heating device according to  FIG. 4 , the pan  18 , which is filled with the foodstuffs to be heated, is placed on the baseplate  45  between the positioning projections  46 . By pulling the handle  35 , the cover  5  is pressed downwards until the hooks  29  grip around the rim of the pan  18  and the pan  18  is coupled to the cover  5 . The force of the spring  42  lifts the pan  18  up until the rotation axis  19  of the pan is at an angle to the vertical. Then, the heating device is switched on, as described above. Once the foodstuffs are sufficiently heated, the pan is pressed between the positioning projections  46  again and the hooks are pressed outwards by pressing the buttons  1 , causing the pan  18  to be detached from the cover  5 . The cover  5  can now move upwards again and the pan  18  with the heated foodstuffs can be removed. It will be clear to those skilled in the art, that the hooks  29 , the positioning projections  46  and the other components are designed such that the cover  5  is able to make this tilting movement. If desired, the pan can slide over the baseplate  45  during the movement or the hinge  40  is designed such that restricted horizontal movements of the cover  5  are possible.