WO2011050486A1

WO2011050486A1 - Installation for reheating portioned fresh, chilled or frozen snack food products

Info

Publication number: WO2011050486A1
Application number: PCT/CH2010/000271
Authority: WO
Inventors: Walter Niemetz
Original assignee: Niemetz, Jerome
Priority date: 2009-10-28
Filing date: 2010-10-27
Publication date: 2011-05-05

Abstract

The invention pertains to an installation (1) for automatic reheating of portioned fresh, chilled or frozen hot snack food products packaged in a food container (24) comprising a lid (25) and a bottom part (29) normally hingedly connected, the installation comprising a drawer (3) for receiving the closed food container (24), a drawer cavity (6) into which upon closing of the drawer (3) the food container (24) is transported, a heating cavity (7) provided with microwave and infrared heating means, and transport elements (12) comprising a fork (14) for automatically transporting the food product without the food container (24) from the drawer cavity (6) into the heating cavity (7) and after heating back to the drawer cavity (6) for repositioning it into the food container (24). The installation is in particular characterized in that the drawer (3) comprises an essentially horizontal bottom element (5) with clamping elements (42) protruding in an essentially vertical direction, wherein at least one clamping element (42) comprises at least two oppositely arranged expansion tongues (46) expanding in a horizontal direction. Furthermore the invention relates to a particularly tailored package for use in such an installation.

Description

TITLE

INSTALLATION FOR REHEATING PORTIONED FRESH, CHILLED OR

FROZEN SNACK FOOD PRODUCTS

TECHNICAL FIELD

The present invention relates to installations for reheating portioned fresh, chilled or frozen snack food products as well as to containers for food for use in such installations and methods of operation of such installations.

PRIOR ART

The consumption of individually packaged cold sandwiches and of other snack products for quick consumption is one of the most well established growth markets in the global food industry, the so called "food on the go" industry. Nevertheless, 90% of all products sold in gasoline stations, kiosks, supermarkets, offices or households, are consumed in a cold state. The traditional products consumed in a warm state, like for instance pizzas, paninis, baguette's, toasts, quiches, strudels etc. are still not offered by the industry as separately packaged snack helpings which can be reheated within one minute by the user/consumer himself at the point of sales or at home.

What is needed therefore is a system whereby the food industry can distribute fresh, frozen or chilled produced single snack portions, for hot or warm consumption, in a functional portion package, whereby the food products are secured during transportation, and packaged in a special merchandising configuration (snack towers) for easy and attractive placement at the point of sales or stored at home.

What is furthermore needed in combination with the functional packaging is a compact convenient to use automated hybrid re-heating equipment integrated in a compact oven, to heat the food product at the point of sales, or in households, within one minute. Further what is needed at the point of sales is an easy attractive merchandising display of the snack products and handling instructions via a TV Video screen integrated in the oven.

Usually, the packaged or unpackaged food product is introduced by the consumer or the sales personnel into the heating device (oven). After a heating period of time the heated food product is taken manually out of the heating device (oven) and returned to the consumer with the heated package, or if it was heated without the package, it is put manually back to its original package (if solid container is used- with film wrapping it is not possible) or placed into a new package and handed over to the consumer. In all these operations are time, staff and additional extra material cost involved and carry a hygienic risk, as very often the personal preparing the food, cashes in also money, and touches at the same time the food. It is for these reasons, that in the European Union the Food & Drug law forbids that the person who is touching money can prepare food. Further, the heating time is not accurately adapted to the food product, the manipulation of the package or the food product does not allow a correct hygienic handling, the manual operation of the heating device is time consuming and erroneous operation occur. A waste factor of 15 % calculated from the net sales price of the food product, is factored into the consumer sales prices as a trade standard, to cover the losses with the handicaps by the existing practice. WO 2006070269 discloses an installation for reheating portioned chilled or frozen snack food products packaged in a lower and upper hinged package parts. It comprises a compact oven provided with a first cavity section infrared heating and a second cavity section heated by microwave means. The package with the food to reheat is taken into the cavity, automatically opened and the food only is unload on a moving grill/fork device. The grill/fork moves sidewards inside the microwave cavity section for microwave heating. A door moves with grill/fork to isolate the microwave heated cavity. After the microwave heating the grill/fork moves inside the infrared cavity section. At the end the food is automatically unloaded back to the package.

SUMMARY OF THE INVENTION

It is an object of the present invention to improve installations for automatic reheating of portioned fresh, chilled or frozen hot snack food products. The main field of application is the essentially complete automatic opening, heating and re-closing operation for essentially fully automated food heating in situations where the food product shall not be touched during this process. So it preferably aims at situations where a closed (optionally sealed, e.g. in an airtight manner and/or tamper proof sealed) food container comprising a food product (usually in a carton insert) shall be automatically put into the installation, automatically unpacked, reheated, and repacked and then delivered from the installation to the personnel or customer.

More specifically the invention relates to an installation for fully automatic reheating of portioned fresh, chilled or frozen hot snack food products packaged in a food container comprising a lid and a bottom part normally hingedly connected. The proposed installation comprising a drawer or drawer like element, typically comprising a bottom element and a cover plate, the drawer being provided for receiving the closed food container and moving it into the installation. The installation further comprises a drawer cavity into which upon closing of the drawer the food container is transported, it further comprises a heating cavity provided with microwave and infrared heating means (either located spatially separated or at the same location), and transport elements, typically comprising a fork for automatically transporting the food product without the food container from the drawer cavity into the heating cavity and after heating back to the drawer cavity for repositioning it into the food container. Typically after repositioning the food container is at least partially, sometimes completely, automatically closed before delivery to the customer.

According to the invention, the drawer preferably comprises an essentially horizontal bottom element which is provided with clamping elements protruding in an essentially vertical direction, wherein at least one clamping element comprises at least two oppositely arranged expansion tongues expanding in a horizontal direction.

In other words specifically tailored holding means for the food package are provided on the drawer. Indeed these holding means or clamping means not only take a function of firmly holding the food package on the drawer, they also serve to accurately position the food product at a clearly defined location. Indeed in the context of these automatic unpacking/heating/repacking machines one of the main problems is the proper removal of the food product from the food package and in particular the accurate repositioning of the food products into the food package after the heating process. Even the smallest inaccuracies in the repositioning of the food product in the food package lead to situations where subsequently the food package cannot be closed anymore leading to a jamming of the machine. As the food product may change shape and dimensions during the heating process, this repositioning is even more important and is only possible, if the food package is not only located on the drawer in the drawer cavity at a clearly defined location, but also at the moment of removal and repositioning of the food products very firmly and safely attached to the drawer.

The compact oven cavity in this context can be closed by a cover plate, which forms part of the transport elements. The drawer is generally shaped to receive and accurately arrange to unpack automatically the food product from the package allowing the re-heating and crispness process to achieve without the package. The installation is provided with means to open automatically the package of the food product, and places it automatically onto a grill/fork device and moves it through the oven cavity provided with two different heating and crispness systems and purposes, said grill/fork device being provided with means allowing the grill/fork device normally under CPU control to be moved inside the oven cavity and take the heated food product moving it back and by doing so re-package the hot food product automatically into the original package. The drawer or the surrounding installation can be provided with means controlled by the CPU designed to close this package containing the heated food product, typically by pressing down the upper part of the package until, if present, snap means between the upper and lower lid are reengaged for secure and convenient self-service take out by the consumer or user.

As mentioned above, according to a preferred embodiment the grill/fork device and the cover plate for the oven cavity are a one piece element or at least attached to each other preferably rigidly attached to each other. This has the effect that if the fork is located in the oven cavity for the heating process the cavity is automatically closed by the cover plate. The food package can be provided with labels with heating instructions. Correspondingly the installation may comprise means for reading a heating instructions label located on the package of the food product and CPU means for controlling the compact oven. As mentioned above, the food package may comprise snap means for closure thereof.

According to a first preferred embodiment, the clamping element comprises a row of circularly arranged expansion tongues, preferably in the range of 4-20, more preferably in the range of 5-12 equally spaced tongues. The tongues are like projecting members, normally projecting essentially perpendicularly from the bottom of the drawer, which are flexible enough that they can be expanded so as to clamp the food package to position and hold it firmly in place.

The tongues can preferably be spread apart for expansion by means of a central pin penetrating from below between the tongues, wherein the pin may comprise a bottom element pointing downwards from the bottom element for cooperation with a stationary guide rail, preferably located below the drawer, such that upon closure of the drawer automatically the central pin is pushed upwards for expansion of the tongues.

According to a further preferred embodiment, at least three clamping elements (preferably arranged in a triangular manner) are arranged on the bottom element, and these clamping elements are arranged such that they are located vertically below a food product packaged in the food container. This arrangement makes sure that the clamping elements are located where all the weight of the food is pushing the food package down as much as possible which contributes to the accurate positioning of the food package.

According to a further preferred embodiment, the fork of the transport element can be heated for a heating of the food product from below, wherein preferably the fork is a resistive heating element.

According to a further preferred embodiment a sensor is located in the drawer cavity or on the transport devices (e.g. a weight sensor) in order to check whether a food product is actually in the cavity and/or loaded on the grill/fork device for safety reasons.

The drawer may further comprise, in accordance with a further preferred embodiment, at least one, preferably two push open elements for automatically opening the food container upon closure of the drawer. In other words, preferably the drawer (and not the surrounding installation elements) comprises the elements for opening the food package. This preferably in a manner such that automatically upon closure of the drawer this opening mechanism is mechanically released. This aspect can also be embodied in such an machine independent of the attaching means of the protruding elements inventive. So the invention also relates to an installation for fully automatic reheating of portioned fresh, chilled or frozen hot snack food products packaged in a food container comprising a lid and a bottom part normally hingedly connected, the installation comprising a drawer or drawer like element, typically comprising a bottom element and a cover plate, the drawer being provided for receiving the closed food container and moving it into the installation, the installation further comprising a drawer cavity into which upon closing of the drawer the food container is transported, it further comprises a heating cavity provided with microwave and infrared heating means (either located spatially separated or at the same location), and transport elements, typically comprising a fork for automatically transporting the food product without the food container from the drawer cavity into the heating cavity and after heating back to the drawer cavity for repositioning it into the food container, wherein the drawer further comprises at least one, preferably two push open elements for automatically opening the food container upon closure of the drawer.

The push open elements preferably comprise noses, preferably penetrating through slots in the bottom element, which are below the upper surface of the bottom element if the drawer is in its open position, and, upon closure of the drawer, move upwards to extend over and above the upper surface of the bottom element.

Below the drawer there is preferentially located in opening guide rail with a ramp for a automatic lifting of the push open elements upon closure of the drawer. According to yet another preferred embodiment the fork comprises rodlike elements moving below the lower surface of the food product, and in that the rodlike elements are provided with spikes for at least partial penetration into the food product or the (cardboard) tray carrying the food product upon lifting thereof. As mentioned above, accurate repositioning of the food product is key to the functioning of the installation without problems. The proposed spikes make sure that the food product, or a carton insert into which the food product is put, remains exactly at the same position on the fork elements during the whole transport and heating process.

Preferentially the heating cavity is located vertically above the drawer cavity, wherein preferably the single heating cavity comprises infrared as well as microwave heating means.

Further preferably, the transport element is mounted in the installation on a bidirectional guide rail system so is freely movable in horizontal and as well as vertical direction, wherein the horizontal mobility is parallel to the loading direction of the drawer.

Further preferably, motion of the transport element is effected by means of a motor-driven mechanism. This for example by means of one or a pair of lever bars operatively coupled to the transport element e.g. via a guiding slot provided in the lever bars, wherein the lever bar is pivotable around a horizontal axis arranged parallel to the loading direction, and wherein the position of the transport element is further controlled by a stationary guide rail into which a guide knob or an equivalent element of the transport element penetrates.

Below the installation there can be located a refrigerator and/or freezer, and/or in that on the front side of the installation above the drawer, there is located a screen for displaying information, preferably a flatscreen display device.

It is important on the one hand that the food product is reheated sufficiently and also in a manner to generate the necessary crispiness on the surface. This necessitates high temperatures in the heating cavity and thus also high temperatures of the food product at the end of the heating process. These temperatures can be well above 60 or 70°C. On the other hand the food product shall, for security reasons, only be delivered to the customer once it has cooled down to a certain extent, typically the temperature of the food product when delivered to the customer should not be above 65°C. In order to make sure that the food product is only delivered at a temperature of not more than 65°C, it is possible, according to a further preferred embodiment, to include a temperature sensor in the drawer cavity which measures, directly or indirectly, the temperature of the food product. The sensor is used to control the machine in the sense that once the heated food product has reached the drawer cavity, the sensor will measure the approximate temperature of the food product. If a temperature at or below 65°C is detected, the drawer will open and the food package at least party or fully be closed and the food product will be delivered. If a temperature of more than 65°C is detected by the sensor, either the food product is just passively allowed to cool down in the drawer cavity (note that the package at this stage is usually open when the drawer is closed), or, preferably, in order to speed up the process, is actively cooled by use of an additional fan or other ventilation device provided in connection with the drawer cavity. So if the sensor detects too high a temperature it will first activate the fan/ventilation such that "cold" air is smoothly blown over and below the food product leading to an active cooling of the food product. As soon as the sensor, which is permanently monitoring the temperature of the food product during this process, detects that the temperature of the food product has fallen below 70°C, or below or equal to 65°C it will stop the fan and then allow the opening of the drawer. The provision of such a fan has the additional advantage that moisture from the interior of the food product reaching the surface of the food product, which then may destroy the crispiness of the surface, is carried away very efficiently from the surface. So the fan not only acts as a cooling device but it also serves to maintain the crispiness of the surface.

It should be noted that this cooling step can on the one hand the implemented in the drawer cavity, it can however also be implemented in the heating cavity. In this case a corresponding sensor can be located in the heating cavity. In the heating cavity a fan for cooling the cavity is often already provided and all one has to do to cool the food product in the heating cavity is to continue operating the fan after the heating elements are switched off. The cooling step may also be implemented somewhere between the heating cavity and the drawer cavity. It is for example also possible to provide a specific further cavity for cooling of the food product.

Generally the installation can be provided with an intake of fresh air (typically located on the backside or on one of the sides of the housing of the installation, the intake may be provided with a filter for filtering the air which is sucked in), optionally even inclusive of a cooling of the intake air, and it can be provided with an output for used, normally hot and humid air. Indeed the heating cavity, in particular the microwave part thereof, and if the above-mentioned active cooling is used in the drawer cavity also the drawer cavity, is usually provided with a fan and the generated hot humid air needs to be transported out of the installation in order to avoid a successive overall heating of the installation. To this end on the backside, on one of the sides, or on the top of the installation there is usually provided an output opening for the used (hot) air. In order to avoid the smell of cooked food in the surroundings of the installation, this opening can be connected to a pipe which directly or indirectly leads out of the room and/or building in which the installation is placed. This output opening/pipe may also be provided with filters, condensation devices and the like in order to avoid smell, humidity and output of small particles.

It should be noted that it is also possible to have several drawer cavities in such an installation and several heating cavities in order to allow parallel heating of food products. Furthermore the present invention relates to a food container (with or without food product in it) for an installation as outlined above. Such a food container comprises a bottom part and a lid (normally) hingedly connected, wherein the bottom part comprises at least two parallel ridges onto which the food product or a tray for the food product can be put or is resting. Between these parallel ridges there are channel like free spaces into which the bars of the fork may penetrate. It may further comprise a carton insert which is open at the top for receiving the food product, at this carton insert is located on the ridges. It furthermore comprises in-line with or partially replacing these ridges at least one, preferably at least three protrusions (each located in a different ridge) of essentially the same height as the ridges formed as blind holes open from the bottom (depth typically in the range of several millimetres) such that the clamping elements can penetrate into and clamp the food container.

The lid preferentially comprises essentially vertical sidewalls with a horizontally extending bottom flange in the region next to the hinge connecting bottom part and lid, preferably at both sides, and the bottom part in this region comprises vertical sidewalls in order to separate the food product also during the opening process towards the side. Specifically at the laterally outer side thereof cutouts are provided which in the closed state are covered by said bottom flanges. These cutouts are specifically provided such that the push open elements mentioned above may travel through these cutouts and then abut with the flanges such as to push open the upper lid.

Preferentially, such a food container is made as one-piece of transparent (or particularly colour) plastic material and in that it further comprises a carton insert for the food product which is positioned on the ridges by positioning elements.

Further preferably such a food container comprises a tamperproof seal which is automatically destroyed upon opening of the food container, and wherein the tamperproof seal comprises the heating instructions in a way such that upon destruction on opening the heating instructions are not readable anymore, wherein preferably the heating instructions are provided in the form of an RFID (radio frequency identification device) tag, which is destroyed upon opening of the food container.

The protrusions of such a food product are preferably located right vertically below the food product and/or any insert comprising the food product.

Such a food container may further preferably be characterised in that in order to avoid shifting of a tray for the food product and/or the food product in the closed package, elements such as notches, ribs, grooves and/or protrusions are provided on the tray and/or the package which keep the tray and/or the food product firmly in place in the package, wherein preferably a tray is provided with side walls of a height such that the upper edge thereof contacts the top wall of the food package if the lid is closed, and the tray is clamped between the bottom part and the lid of the package.

Further preferably the inner side of the lid of the package can be provided with ribs and/or knobs/protrusions or the like penetrating downwards into the interior of the package, this for example with a height of the ribs in the range of 2-15 mm. The height of the ribs and/or is chosen such that the food product (optionally located in a tray) is clamped (not full surface clamping) between these ribs and the bottom of the package. Like that during transport it is not possible that the food product gets stuck on the lid, e.g. if the food container is transported with the wrong side pointing upwards.

The food product can be essentially triangular, square, rectangular, circular or part circular. Further embodiments of the invention are laid down in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described in the following with reference to the drawings, which are for the purpose of illustrating the present preferred embodiments of the invention and not for the purpose of limiting the same. In the drawings,

Fig. 1 shows in a) schematic side view an illustration of the oven and in b) shows a schematic front side view of the oven;

Fig. 2 shows a schematic illustration of the transport mechanism of the oven, wherein in a) the receipt position of the transport element is illustrated, and in b) an intermediate position and the heating position of the transport element are illustrated;

shows several illustrations of a triangular food container with half open lid, wherein in a) a front view, in b) a top view, in c) a side view, in d) a perspective view, each time without carton insert are shown and in e) a side view with carton insert, and in f) a perspective view with carton insert are shown;

shows several illustrations of a rectangular food container with half open lid, wherein in a) a perspective view without carton insert, and in b) a perspective view with carton insert is shown;

shows illustrations of the drawer with a triangular food container loaded, wherein in a) a side view with an open container, in b) a top view with an open container, in c) a front view with an open container, in d) a cut in a plane perpendicular to the loading direction through the position where the push open elements are located, and in e) a perspective view are given; shows illustrations of the clamping mechanism of the drawer with a triangular food container loaded each time with an open and with a closed drawer, wherein in a) a side view with an open container, in b) a cut in a plane through the central clamping element and parallel to the central guide rail, in c) a top view are shown, and wherein in d) details of the clamping mechanism are shown in a cut perpendicular to the loading direction, and wherein in e) the details as designated with the dashed circle x in figure b) are given;

shows illustrations of the food container opening mechanism of the drawer wherein in a) the open drawer and the closed drawer position are shown without food container and in b) with food container loaded, each time cuts parallel to the loading direction are given;

shows a detailed cut through the oven inclusive of the heating cavity but with some of the transport elements removed; and

shows a detailed cut through the oven inclusive of transport elements.

DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 shows in a in a schematic side view the main elements of an installation or oven 1 according to the present invention. The installation comprises in its lower part a drawer 3 which can be opened and closed and which comprises a cover plate 4 as well as bottom element 5. This drawer 3 moves in and out of a drawer cavity 6 which is open to the left and the right, so which is a channel like structure. From the right side it is, the drawer is closed, essentially closed by the cover plate 4 of the drawer 3. Towards the backside of the drawer cavity 6, so in figure 1 on the left side, there is located a transport element 12 which comprises a fork 14 which penetrates into the cavity 6 as well as a vertical cover plate 13. This cover plate 13 serves, in the position where the transport element is moved to the heating position, as the closing cover for the heating cavity. The fork 14 on the other hand travels underneath the food product accessible in the automatically opened food package and lifts and transports it as will be detailed further below.

The heating cavity 7 is located vertically above the drawer cavity 6, and this heating cavity 7 is a single cavity which at the same time is provided with microwave heating facilities as well as in infrared heating means. The infrared heating means are located typically in the top and bottom parts of the cavity, however if the fork 14 itself is structured as a heating element (resistive heating element), the infrared heating means of the bottom part of the cavity can be at least partially or completely replaced by this heating possibility of the fork. Typically the heating process in this heating cavity 7 is carried out in that first the microwave is used for unfreezing the product, and for heating to a minimum temperature, and subsequently the infrared heating is used for generating the crispiness.

The installation 1 further comprises a motor 8 for moving the transport element 12 as will be illustrated further below, and it comprises a control and or power supply element 9 which is only schematically illustrated. This control element may comprise a computer with internet access not only for controlling the heating process and the transport process but also for interacting with the food package (reading and processing of product information), with the operator as well as with databases which can be internal but also external (accessible via Internet). Typically the installation comprises a top wall, a bottom wall, side walls, a backside wall as well as a front side cover 2.

In figure 1 b) this oven is shown in a front view. As one can see, the cover plate 4 of the drawer is located in the lower part of the installation. In the upper part it is possible to locate a screen 11 on the front side wall 2, and this screen 11 can e.g. be used for user information, advertisement, process control, etc. It can for example also be a touch screen such that during the heating process further instructions or information can be provided to the user. In the alternative next to or below the screen input means such as a keyboard can be located. It is for example possible to inform the customer waiting for the heated product about additional products or services separate or in relation with the heated product, so about beverages, non heated food products, or also about charity donation possibilities. So essentially add-on order possibilities can be advertised and activated this way.

It is for example possible to provide an integrated system as follows:

1. Identification of the product and/or services: an RFID tag/initiator (or another readable device such as a barcode) is provided on the food package activating the provider installation (also for controlling the heating process) This RFID tag/initiator is attached to the food package. The RFID tag concerns the identification of the product/service and the location of the installation, as well as heating instructions, product information etc.

2. The installation is provided with a reader (e.g. an RFID tag reader) and optionally writer capabilities, integrated in the installation and connected to a central computer which is part of the installation or a control element. The installation is started/controlled by the RFID tag initiator. It is connected to consumer products or services and as a reader in the machine detects it, it activates the whole process, inclusive of the computer and its content management.

3. An internet connected computer in the installation, transmitting the information to a central mainframe computer returning client data/product data/heating instruction data or any other kind of associated data, which can subsequently be displayed on the TV monitor. On the spot proof, amount, time, incentives the purpose of e.g. donation by ticket included in the TV monitor is possible.

Figure 2 shows the functioning of the transport mechanism of the installation. On the very right side the drawer 3 is shown in the open position. It is also shown in the closed position where the cover plate 4 essentially closes the drawer cavity 6. When the drawer 3 closes, the food product container is shifted into the cavity 6 in a way such that it is automatically opened (as will be outline further below), and such that the bar like elements of the fork 14 can penetrate into the food package and below the food product (or a tray within which the food product is placed) so as subsequently to be able to lift it and remove it from the food package.

The fork carrying the tray or the food product can have bar like fingers with around cross- section or it may have has wider and flat fingers covering up to 80% of the bottom surface of the tray. The fork fingers in this case can be of a construction such that they can be heated up to 240° C and replace the bottom tube infrared heating.

The concentrated heat close to the product will toast the outside of the lower part of the snack - and in the case of a Hamburger or a Ham and Cheese Toast make it crunchy. The "crunchy Hamburger" bread, provides a new eating sensation, compared with the cold soft bread in the traditional Hamburgers. Preliminary tasting with toasted Cheeseburgers gives a new character to these Hamburgers.

The top part of the product is heated with infrared means in the heating cavity with the tubes in different configuration close to the bread.

The transport element 12 is there to transport the food product (alone or are located in the tray) after the removal from the food package (the food package remains in the cavity 6 during the whole process), from the drawer cavity 6 to the heating cavity 7. This is realized in that the transport element 12 is mounted in the installation on a bidirectional suspension 20. This means that the transport element 12 is, within certain boundaries, movable in vertical as well as horizontal direction, specifically the horizontal direction is given by the direction of closure of the drawer 3. This y-directional suspension 20 can be realized, as illustrated schematically here, by providing a vertical guide rail 21, which is located stationary, and on which, vertically movable, there is mounted a horizontal guide rail 22 (x-directional suspension), on the horizontally movable element thereof the transport element 12 is mounted in a rotationally fixed manner. The transport element 12 can be moved horizontally and vertically on the suspension device while the fork 14 always remains in the horizontal orientation. It is of course possible to interchange the vertical guide rail 21 and the horizontal guide rail 22, so it is possible to have a stationary horizontal guide rail 22 and a movable vertical guide rail 21.

In order to control the coordinates of the transport element within these two dimensional mobility area which is accessible to the transport element 12, there can be provided to independent motors for the two axes which are controlled in a synchronised manner. In the alternative, as shown in the figure, the motion can be controlled by providing two elements, one for driving it and one for controlling the position. The drive is realized by a lever bar 15, which is preferably mounted on a rotation axis 16 and which is driven by motor 8 coupled via element 19 to the lever bar 15. The lever bar 15 on its free end is provided with a guiding slot 17, into which a corresponding travelling pin 18 of the transport element 12 penetrates.

If the lever bar 15 in figure 2a rotates in a clock wise direction, it will shift the transport element 12 side ways and upwards and eventually to an intermediate position at half height as illustrated on the left side of figure 2b. Upon further rotation it will then move the transport element 12 further upwards and in a manner such that the fork (and the food product placed thereon) will penetrate into the heating cavity 7 and finally the cover plate 13 of the transport element 12 will close the insertion opening 23 of the heating cavity 7. This is illustrated on the top part of figure 2b, as the heating position. Also illustrated is the corresponding position of the horizontal guide rail 22 in the heating position.

In other words in the heating position the cover plate 13 which forms part of the transport element 12 is at the same time the oven door.

In order to provide for an accurate control of the position of the transport element, further a specific guide slot or guide rail 56 is provided, as it is illustrated in figure 9. These guide rails are typically located on the inner side of the side walls of the installation and there are provided guide knobs, guide protrusions or guide rolls on the transport element 12 which penetrate into this guide rail 56 to travel therein and be guided thereby. This guide rail 56 determines, as a function of the y-coordinate, the x-coordinate of the transport element 12 (and vice versa) and therefore defines an accurate and appropriate travelling trajectory for the motion between the position where the fork is located in the drawer cavity 6 and the position where the fork is located in the heating cavity 7.

The whole installation is ideally suitable and adapted to a use together with food packages as illustrated in figure 3 and figure 4. Such a food container 24 comprises a bottom part 29 and a lid 25, which are connected with each other via a hinge 28 (typically a film hinge). The lid 25 comprises essentially circumferentially downward projecting side walls 27. The bottom part 29 of this essentially triangular food container is provided with a set of parallel ridges 30, so that between these ridges 30 there are channels into which the bars of the fork 14 may penetrate in order to lift the food product. The food product is typically located in or on a carton insert 39 or tray as illustrated in figures 3e and in order to allow for accurate positioning of this carton insert 39, the ridges 30 are provided with positioning elevations 38 and at the back side of the bottom part there is located a back wall portion 34. Further more on the side of the bottom part there are located side walls 33 which form part of the bottom part 29 as well.

The ridges 30 are either partially replaced or in the lateral case, fully replaced by protrusions 32, which are open towards the bottom. These protrusions have essentially the same height as the top of the ridges 30. These protrusions 32 are provided such that the clamping elements 42, which will be discussed in more detail below, may penetrate from below into these protrusions 32 and by expanding on the cylindrical side walls or rather the inner side thereof attach the food package to the drawer.

Another important feature of this type of food package is the fact that the side walls 33 extend high up and essentially almost to the top wall 26 of the lid 25. On the laterally outer side these side walls 33 or rather the bottom flanges thereof are provided with recesses or cutouts 36. The side walls 27 of the lid at this position are provided with an essentially parallel to top wall 26 flange 37.

So if the food package is in the closed state, this flange 37 will cover the recess 36. On the other hand in the region of this recess 36 this bottom flange 37 may then serve as abutment surface for the push open elements 40 which will be discussed further below. Due to the height of the side walls 33 the push open element 40 can not interfere with any kind of food product located within the food package.

In order to avoid shifting of the tray and/or the food product in the closed package, it can be advantageous to provide elements/protrusions on the tray and/or the package which keep the tray and/or the food product firmly in place in the package to avoid shifting around or food particles being stuck to the upper part of the packaging until reaching the point of sales or the final use in the oven installation. To achieve this firm positioning of the food product and/or of the tray within the package for transport, it is possible to e.g. provide a tray with side walls of a height such that the upper edge thereof contacts the top wall of the food package if the lid is closed, so the tray is clamped between the bottom part and the lid of the package.

In the central portion of the lid 25 of the food package there may be provided a depression 35 for heating aids/labelling etc. In the region of this depression there can be provided several further downward pointing ribs, e.g. arranged perpendicular to the hinge between the top and the bottom part of the package. The height of these ribs (not illustrated in the figure) is then chosen such that the lower face thereof essentially touch the food product present in the tray and thereby clamp the food product between the ribs and the bottom of the tray. Like this the food product is held firmly in the package for transportation, and if for example by error the food package is transported the reverse way, it is prevented that the food product gets full surface pressed against the upper lid.

Figure 4 illustrates a rectangular food package of similar type, other forms such a circular, square or part circular are possible. Typically the opening angle a as illustrated in figure 3e should be in a range of 20-50 degrees. Of course the package should just be minimally opened and the food product shifted out of the package at the minimum opening position in order to allow an as small as possible cavity and thus a most compact installation design. One important feature of the invention is the specific design of the drawer 3, as it is illustrated in figure 5.

Figure 5 focuses on the opening mechanism for the lid 25. This opening mechanism comprises half circle like push open elements 40, which may penetrate through slots 41, which are provided in the bottom part 5 of the drawer. These elements 40 are in the receded position if the drawer is open, so they don't penetrate above the upper surface of the bottom part 5 of the drawer. Therefore it is possible to locate the food package on the open drawer 3 in the closed state of the package. Upon motion of the drawer 3 into the drawer cavity 6, specifically at the very end of the motion of the drawer 3 into the cavity 6, the push open elements 40 are mechanically lifted such that they start pushing upwards the lid near the hinge by abutment onto the lower surface of the flange 37, leading to an automatic opening of the lid 25 when the drawer 3 is closing.

Figure 6 focuses on another mechanically coupled mechanism of the drawer, namely on the mechanism for holding the food container 24 in a proper position. To this end expansion pins 44 of clamping elements 42 are provided on the bottom element 5 of the drawer 3. These expanding pins 44 are permanently protruding above the upper surface of the bottom element 5. They are provided as a ring of tongues 46, in the center of which there is provided essentially a blind hole accessible from below. The tongues 46 on their inner sides are provided with a ramp like structure such that if a pin is pushed into the hole from the lower side, the tongues 46 radially expand. These expansion pins 44 penetrate, upon placement of the food package 24 on to the drawer, into the blind holes of the protrusions 32 as mentioned above. If the tongues 46 are spread, they will get into frictional contact with the inner side of the side walls of the protrusions 32 and attach the food package to the drawer 3.

On the bottom side the clamping elements 42 are provided with a rounded bottom 47. This rounded bottom 47 is spring loaded together with the pin it forms part of, in a downwards direction by means of a pressure spring coil 45. So if the rounded bottom 47 of the expansion pin is not pushed upwards by some additional element, it will remain in the retracted position which is defined by an abutment. Only if the rounded bottom 47 and the pin connected therewith is pushed upwards against the spring force of the coil 45, the tongues 46 will radially expand and thereby firmly hold the food package via the protrusions 32.

This clamping is automatically activated mechanically when the drawer 3 moves into the closed position. This can be seen in particular by looking at figure 6. If the drawer 3 moves from the open position displayed on the right side to the closed position displayed in the middle, the rounded bottom 47 will come into contact with a specifically provided guide rail 48, at each lateral position where a clamping element 42 is located such a guide rail 48 is located. As soon as the rounded bottom 47 reaches a ramp 49 or just a starting point of a guide rail 48, it will be pushed upwards leading to a radial clamping and corresponding attachment of the food container on the drawer.

Figure 7 illustrates again the mechanism of the push open elements 40. On the right side there is displayed the situation where the drawer is in the open position. In this position the push open element 40 is in the retracted position, so the semi circular nose 45 is within and below the slot opening 41 and thus does not protrude above the upper surface of the bottom element 5. Again typically the push open element 40 is either spring loaded to be in the retracted position or it is held in the retracted position by gravity. Typically a pair of such push open elements 40 is located to interact with both lateral sides of the food package or rather the flanges 37 thereof for automatic opening of the package upon closure of the drawer 3.

If the drawer 3 now moves to the left into the closed position, these push open elements 40 are moved upwards due to interaction with an opening guide rail 51 which is stationary located and which on its right side is provided with a ramp 52. The push open elements 40 comprise a corresponding negative ramp 53, such that the ramp 53 upon closure of the drawer 3 will travel on the ramp 52 leading to a lifting of the semicircular nose 54 and correspondingly to an opening of the lid by abutment on the flange 37 thereof.

Figure 8 shows a more detailed cut in a plane vertical and parallel to the loading direction 50 of the drawer. Here one can see that indeed it is possible to locate the cavity 6 for the drawer closely below the heating cavity 7 and that this cavity 6 does not have to be high as even a small opening angle of around 22 degrees is sufficient to remove and take out the food product in the carton insert 39. In this case a mechanism is shown, in which there is no lever bar transport, but where there is a simple bidirectional motor/suspension driving the fork of the transport element. For taking out the carton insert 39 out of the opened food product located in the drawer cavity, this motor just drives to the left, subsequently the horizontal motor is deactivated and the vertical motor is switched until the proper height is reached, which is schematically illustrated by the carton insert 39 displayed in the upper left part, and then the horizontal motion is activated again towards the right side to move the fork into the heating cavity and at the same time close the heating cavity by the cover plate 13. This heating position is schematically illustrated by the carton insert 39 shown in the heating cavity 7.

Figure 9 on the other hand shows a mechanism where there is provided above-mentioned guide rail 56 to define a proper travelling behavior of the transport element 12 in each state.

LIST OF REFERENCE SIGNS

1 oven 23 insertion opening of 7

2 frontside of 1 24 food container

3 drawer 25 lid of 24

4 cover plate of 4 26 top wall of 25

5 bottom element of 4 27 sidewalls of 25

6 drawer cavity 28 hinge between 25 and 29

7 heating cavity 29 bottom part of 24

8 motor 30 ridge of 29

9 control/power supply 31 insertion channels of 29

10 sidewalls of 1 32 protrusion

11 screen 33 side wall of 29

12 transport element 34 back wall of 29

13 cover plate of 12 35 depression for heating

14 fork aids/label

15 lever bar 36 recess/cutout in 29

16 rotation axis of 15 37 bottom flange on 27

17 guiding slot in 15 38 positioning elevation on 30

18 travelling pin 39 carton insert for holding food

19 gearing element/coupling piece

element 40 push open element

20 bidirectional suspension of 12 41 slot opening in 5 for 40

21 vertical guide rail of 20 42 clamping elements

22 horizontal guide rail of 20 43 slide rail for 5 expansion pins of 42 50 loading direction of drawer pressure spring coil of 42 51 opening guide rail circular arrangement of 52 ramp of 51

expansion tongues of 42 53 triangular ramp element of 40 rounded bottom of expansion 54 semicircular nose of 40 pin 55 connecting bar for the two guide rail for control of 42 push open elements ramp of 48 56 guide slot/guide rail

Claims

1. Installation (1) for automatic reheating of portioned fresh, chilled or frozen hot snack food products packaged in a food container (24) comprising a lid (25) and a bottom part (29) hingedly connected, the installation comprising a drawer (3) for receiving the closed food container (24), a drawer cavity (6) into which upon closing of the drawer (3) the food container (24) is transported, a heating cavity (7) provided with heating means such as microwave and infrared, and transport elements (12) comprising a fork (14) for automatically transporting the food product without the food container (24) from the drawer cavity (6) into the heating cavity (7) and after heating back to the drawer cavity (6) for repositioning it into the food container (24)

characterized in that

the drawer (3) comprises an essentially horizontal bottom element (5) with clamping elements (42) protruding in an essentially vertical direction, wherein at least one clamping element (42) comprises at least two oppositely arranged expansion tongues (46) expanding in a horizontal direction.

2. Installation according to claim 1, characterised in that the clamping element (42) comprises a row of circularly arranged expansion tongues (46), preferably in the range of 4-20, more preferably in the range of 5-12 equally spaced tongues (46).

3. Installation according to any of the preceding claims, characterised in that the tongues (46) are spread apart for expansion by means of a central pin penetrating from below between the tongues (46), wherein preferably the pin comprises a bottom element (47) pointing downwards from the bottom element (5) for cooperation with a stationary guide rail (48), preferably located below the drawer (3), such that upon closure of the drawer automatically the central pin is pushed upwards for expansion of the tongues (46).

4. Installation according to any of the preceding claims, characterised in that at least three clamping elements (42) are arranged on the bottom element (5), and wherein these clamping elements (42) are arranged such that they are located vertically below a food product packaged in the food container (24).

5. Installation according to any of the preceding claims, characterised in that the fork (14) of the transport element (12) can be heated for a heating of the food product from below, wherein preferably the fork is a resistive heating element.

6. Installation according to any of the preceding claims, characterised in that the drawer (3) comprises at least one, preferably two push open elements (40) for automatically opening the food container (24) upon closure of the drawer (3).

7. Installation according to claim 6, characterised in that the push open elements (40) comprises noses (54), preferably penetrating through slots (41) in the bottom element (5), which are below the upper surface of the bottom element (5) if the drawer (3) is in its open position, and, upon closure of the drawer (3), move upwards to extend over and above the upper surface of the bottom element (5).

8. Installation according to claim 7, characterised in that below the drawer (3) there is located in opening guide rail (51) with a ramp (52) for a automatic lifting of the push open elements (40) upon closure of the drawer (3).

9. Installation according to any of the preceding claims, characterised in that the fork (14) comprises rodlike elements moving below the lower surface of the food product, and in that the rodlike elements are provided with spikes for at least partial penetration into the food product upon lifting thereof.

10. Installation according to any of the preceding claims, characterised in that the heating cavity (7) is located vertically above the drawer cavity (6), wherein preferably the single heating cavity (7) comprises infrared as well as microwave heating means.

11. Installation according to any of the preceding claims, characterised in that the transport element (12) is mounted in the installation on a bidirectional guide rail (20) freely movable in horizontal and as well as vertical direction, wherein the horizontal mobility is parallel to the loading direction (50) of the drawer (3).

12. Installation according to claim 11, characterised in that motion of the transport element (12) is effected by means of a motordriven lever bar (15) operatively coupled to the transport element (12) via a guiding slot (17), wherein the lever bar (15) is pivotable around a horizontal axis arranged parallel to the loading direction (50), and wherein the position of the transport element (12) is controlled by a stationary guide rail (56) into which a guide knob of the transport element (12) penetrates.

13. Installation according to any of the preceding claims, characterised in that below the installation there is located a refrigerator and/or freezer, and/or in that on the front side of the installation above the drawer, there is located a screen for displaying information, preferably a flatscreen display device.

14. Food container (24) for an installation according to any of the preceding claims, comprising a bottom part (29) and a lid (25) preferably hingedly connected, wherein the bottom part comprises at least two parallel ridges (30) onto which the food product, preferably in a carton insert (39) which is open at the top, is placed, and wherein it comprises in-line with these ridges (30) at least one, preferably at least three protrusions (32) of essentially the same height as the ridges (30) formed as blind holes open from the bottom such that the clamping elements (42) can penetrate into and clamp the food container.

15. Food container according to claim 14, characterised in that the lid (25) comprises essentially vertical sidewalls with a horizontally extending bottom flange (37) in the region next to the hinge (28) connecting bottom part (29) and lid (25), preferably at both sides, and in that the bottom part (29) in this region comprises vertical sidewalls (33) and at the laterally outer side thereof cutouts (36) which in the closed state are covered by said bottom flanges (37).

16. Food container according to any of the preceding claims 14 or 15, characterised in that it is made as one-piece of transparent plastic material and in that it further comprises a carton insert for the food product which is positioned on the ridges (30) by positioning elements (38).

17. Food container according to any of the preceding claims 14-16, characterised in that it comprises a tamperproof seal which is automatically destroyed upon opening of the food container, and wherein the tamperproof seal comprises the heating instructions in a way such that upon destruction on opening the heating instructions are not readable anymore, wherein preferably the heating instructions are provided in the form of a barcode and/or an RFID tag for activation of the process via a reader in the installation, which barcode/RFID tag is optionally destroyed upon opening of the food container.

18. Food container according to any of the preceding claims 14-17, characterised in that the protrusions (32) are located right vertically below the food product and/or any insert (39) comprising the food product.

19. Food container according to any of the preceding claims 14-18, characterised in that in order to avoid shifting of a tray for the food product and/or the food product in the closed package, elements and/or protrusions are provided on the tray and/or the package which keep the tray and/or the food product firmly in place in the package and/or in the tray, wherein preferably a tray is provided with side walls of a height such that the upper edge thereof contacts the top wall of the food package if the lid is closed, and the tray is clamped between the bottom part and the lid of the package.

Food container according to any of the preceding claims 1 -19, characterised that it is essentially square, circular, triangular, rectangular or part circular.