Method for determining the need for cleaning of a commercial cooking appliance, and commercial cooking appliance

Abstract

Method for determining the need for cleaning of a commercial cooking appliance with at least one cooking surface, characterized by the steps: - Capturing at least one image of at least part of the cooking surface and / or at least part of a cooking product to be cooked or cooked by an optical recognition device, - Comparing the captured image of the cooking surface area with a pre-stored reference image of a dirty cooking surface requiring cleaning, and / or the captured image of the product to be cooked or cooked with a pre-stored reference image of the product in a state of cooking that indicates a need for cleaning the cooking surface, and - Decide, based on the result of the comparison, whether cleaning is necessary.

Description

[0001] The present invention relates to a method for determining the need for cleaning a commercial cooking appliance, according to the preamble of claim 1. Such a method is known from DE 101 28 024 B4. Furthermore, the present invention relates to a cooking appliance according to the invention as per claim 10.

[0002] Commercial cooking appliances are cooking appliances used for commercial purposes. These include, for example, grills, conveyor ovens, combi steamers, deep fryers, kettles, cooking vessels, ovens, and microwave ovens.

[0003] Commercial cooking equipment becomes soiled due to its frequent use. Depending on the type of cooking and the products being cooked, different types and degrees of soiling can be expected over varying periods. For example, commercial cooking equipment may become soiled more frequently and with greater intensity when cooking high-fat products, such as roast chicken or roast beef, compared to other products, such as cakes or bread. Since soiling of the cooking equipment is critical to the quality of the cooked product, its safety for human consumption, and the efficient operation of the equipment, it must be detected and recorded so that the cooking equipment and its accessories can be cleaned.

[0004] Commercial cooking appliances, such as combi steamers, are typically equipped with automatic cleaning systems for cleaning the cooking chamber. Such cleaning systems are described in EP 1 473 521 A1, EP 1 717 518 A1 and EP 1 953 458 A1.

[0005] In an existing cleaning system, the cooking processes since the last cleaning cycle are taken into account, and the cleaning system can suggest a cleaning sequence based on a certain degree of soiling. Another existing cleaning system offers an environmentally friendly option that allows: (a) skipping a drying step after cleaning, (b) skipping a rinsing step, or (c) reducing the amount of water used.

[0006] Furthermore, another cleaning system is known from EP 1 953 457 A1. This involves an automatic cleaning method for removing soiling, limescale, and / or corrosion based on a degree of soiling. The degree of soiling is determined using a turbidity sensor. After the degree of soiling has been determined, a number of cleaning points, i.e., cleaning times, are determined for repeated cleaning cycles, each defined by a first time T1 and a second time T2. EP 1 953 457 A1 also discusses in general the aspect of determining a cleaning sequence based on time values, temperature values, and values ​​of a mechanical and a chemical action.

[0007] Furthermore, a method and a device for providing a flexible cleaning sequence for cooking appliances are known. The operator of the cooking appliance can vary the parameters of a cleaning program so that the cleaning of the cooking appliance can be adapted to the soiling conditions of the cooking appliance, and the cleaning program can be selected with a view to saving water, energy, and cleaning agents.

[0008] However, all these cleaning systems and methods determine the need for cleaning based on the operating times and / or operating modes (cooking programs) of the cooking appliance. Therefore, these systems and methods do not offer a dynamic way of determining the degree of soiling of the cooking appliance or the quality of the food being cooked or already cooked, on which basis the cooking appliance is switched off.

[0009] Furthermore, various cooking appliances are known from the prior art in which the product to be cooked can be identified. These cooking appliances generally include a product detection device, for example, a camera. The camera is generally positioned outside the cooking appliance in such a way that a product to be placed in the cooking appliance is within the camera's field of view. These appliances can also automatically provide cooking programs for the identified products.

[0010] The cleaning systems and procedures described above have several disadvantages. Most of these systems and procedures rely on operator observation or indirect detection of the degree of soiling via a sensor to determine whether the cooking appliance needs cleaning and to select a cleaning program. Therefore, errors can occur when determining whether cleaning is necessary. In particular, this does not guarantee proper cleaning of the cooking appliance. It is also possible that the cooking appliance will continue to be used when it should be cleaned. The result is a deterioration in the quality of the cooked product; at best, the product will appear unappealing, and at worst, it will be unfit for human consumption.This can lead to dissatisfied customers and / or waste of cooked products, resulting in a loss of profit. Furthermore, the described cleaning systems and procedures cannot predict the need for cleaning during the next cooking process.

[0011] It is therefore an object of the present invention to propose a method for determining the need for cleaning a commercial cooking appliance, whereby an objective and current determination of the need for cleaning the cooking appliance can be made possible.

[0012] This problem is solved by the features of claim 1.

[0013] Specifically, this task is solved by a method for determining the need for cleaning a commercial cooking appliance with at least one cooking surface, comprising the steps of capturing at least one image of at least a part of the cooking surface and / or at least a part of a cooking product, comparing the captured image of the part of the cooking surface with a pre-stored reference image of a soiled cooking surface requiring cleaning, and / or comparing the captured image of the part of the cooking product with a pre-stored reference image of the cooking product in a state of cooking that indicates a need for cleaning the cooking surface, and deciding, based on the result of the comparison, whether cleaning is necessary.

[0014] The method according to the invention offers the advantage that the need for cleaning the cooking surface of the cooking appliance is determined by its current level of soiling. This allows a decision to be made as to whether cleaning the cooking surface is actually necessary. In this respect, cleaning that is solely triggered by the fact that a certain number of cooking cycles have taken place and / or a certain operating time of the cooking appliance has been reached can be avoided. This leads to more efficient operation of the cooking appliance and significant savings in water, energy, and cleaning agents.

[0015] Furthermore, determining whether the cooking surface needs cleaning or when cleaning is required is not subject to the subjective judgment of the cooking appliance operator. On the contrary, this can be done reliably and in real time. This ensures high-quality cooked products.

[0016] The need for cleaning can first be determined by observing the cooking surface of the cooking appliance and assessing its level of soiling. A cooking surface could be, for example, one or more walls of the cooking chamber, the inner surface of a door used to open or close access to the cooking chamber, the griddle plates of a grill, or the surface of a conveyor belt in a continuous oven. Alternatively or additionally, the need for cleaning the cooking surface can be determined by observing a product being cooked or at least one surface of the product being cooked or at least one surface of the product being cooked or at least one surface of the product being cooked or at least one surface of the product being cooked.

[0017] The degree of soiling or the need for cleaning of the cooking surface is determined by comparing the captured image of the cooking surface and / or the food being cooked with pre-stored reference images. Based on this comparison, a decision can be made as to whether cleaning of the cooking surface is necessary. Subsequently, suitable cleaning methods can preferably be suggested or pre-selected.

[0018] For example, if the cooking surface becomes coked due to fat burning, cok particles detached from it can settle onto the food being cooked. Therefore, the image of the food being cooked can indicate contamination of the cooking surface.

[0019] Furthermore, it is an object of the present invention to create a cooking appliance in which an objective determination of the need for cleaning of the cooking appliance can be ensured.

[0020] This problem is solved by the features of claim 10.

[0021] In detail, this problem is solved by a quality management monitoring system of a commercial device according to the invention with at least one cooking surface, which comprises an optical detection device directed at at least a part of the cooking surface and / or at least a part of a product to be cooked or cooked, and a control device that is in signal communication with the optical detection device.The control unit includes a first memory for images of the part of the cooking surface and / or the part of the cooking product captured by the optical recognition device, a second memory for reference images of a dirty cooking surface requiring cleaning, and / or for reference images of cooking products in a state of cooking that indicates a need for cleaning, and a comparator. The comparator is in signal communication with the first memory and the second memory for comparing the captured images with the reference images.

[0022] The dependent claims contain advantageous further developments of the present invention.

[0023] Preferably, the current cooking process can be interrupted, preferably automatically, or the cooking appliance can be switched off if the cooking surface requires cleaning. This automatic interruption of the cooking process or automatic switching off of the cooking appliance prevents a reduction in the quality of the cooked product, even if the operator is engaged in other tasks. Therefore, constant monitoring of the cooking appliance by the operator is not necessary.

[0024] Preferably, the remaining cooking time until the end of the current cooking process is compared with a predetermined time threshold. The cooking appliance is only switched off after the remaining cooking time has elapsed if it is less than the predetermined time threshold. This allows cooking processes where the remaining cooking time is less than the predetermined time threshold to be completed first before the appliance is switched off. In such cases, where a cooking cycle or program is nearly complete, interrupting the cooking process or switching off the appliance immediately after determining the need for cleaning would offer only a slight overall advantage for the operation of the appliance and would not noticeably impair the quality of the cooked product.

[0025] Advantageously, a current degree of soiling is calculated and / or a current soiling type is determined based on the captured image of the cooking surface and / or the food being cooked. This allows for a quantitative determination of the soiling status of the cooking surface. The soiling status or cleaning requirement of the cooking surface can then be determined by comparing the current soiling type with preset or known values. The captured soiling type is preferably taken into account when calculating the current degree of soiling.

[0026] According to a preferred embodiment of the present invention, the need for cleaning is determined for the next cooking process. Preferably, the degree of soiling of the cooking surface of the cooking appliance can be measured and compared with the next anticipated cooking process. If, in the next anticipated cooking program or cycle, it is likely that the determined degree of soiling of the cooking surface will exceed an acceptable, predetermined degree of soiling and / or an acceptable, predetermined quality level of the cooked product, cleaning of the cooking appliance can be suggested or required before the start of the next anticipated cooking program or cycle. Thus, the method has an anticipatory or predictive aspect.

[0027] It is particularly preferred that the expected degree and / or type of soiling of the cooking surface in the next cooking process be determined based on the current degree and / or type of soiling of the cooking surface, and / or the remaining cooking time until the end of the current cooking process, and / or the cooking time of the next cooking process. It is preferably proposed or required that the cooking surface be cleaned before the start of the next cooking process if the expected degree of soiling necessitates cleaning. This is particularly advantageous if there is no need for cleaning at the current degree of soiling. Thus, it can be predicted whether cleaning will likely be necessary in the next cooking process.

[0028] In such a case, it is advantageous to switch off the cooking appliance after the current cooking process has ended.

[0029] To clean the cooking surface, a cleaning program is preferably selected from pre-stored programs based on the current and / or expected degree and / or type of soiling. Based on the specific degree of soiling, the quality management monitoring system can suggest any number of cleaning processes. These include, for example, simple brush cleaning, manual cleaning with any cleaning agent, an automatic cleaning cycle using detergents or descaling agents, etc. Additionally, the quality management monitoring system can interrupt the operation of the cooking appliance to ensure optimal cooking results and to prevent potential health problems and / or damage to the appliance.

[0030] Preferably, a warning signal is emitted when the cooking surface requires cleaning. This cleaning requirement can arise during the current and / or the next cooking process. This alerts the operator that the cooking appliance needs cleaning and / or that the next cooking program or cycle should not begin. The warning signal can preferably be an alarm, a flashing light, a message on a user interface (such as a display or other part of the cooking appliance), a vibration (in the case of a wireless or portable device), or similar signaling methods indicating that the cooking appliance needs cleaning and / or that its operation must be interrupted until it is cleaned.

[0031] If it is determined that the quality of the cooking product or the cooking surface of the cooking appliance is inferior, for example in the case of excessive browning, an excessive number of spots on the surface of the cooking product or excessive fat formation on the cooking surface of the cooking appliance or in the cooking chamber, a warning signal is preferably given.

[0032] According to a preferred embodiment of the present invention, the emitted warning signal and / or a switched-off state of the cooking appliance and / or an interrupted state of the cooking process can be overwritten and / or canceled when an operator of the cooking appliance switches the appliance back on.

[0033] Advantageously, images of the cooking surface and / or the food being cooked are captured continuously or at predetermined time intervals. This allows for a dynamic determination of whether cleaning is necessary, by analyzing the food being cooked and / or the cooking surface of the appliance during the cooking process.

[0034] The optical recognition device is preferably designed digitally.

[0035] For capturing images, the optical recognition device is preferably equipped with a digital image capture element, in particular an electronic image sensor. The electronic image sensor can be designed as a CCD sensor or a CMOS sensor.

[0036] The optical recognition device is preferably configured such that the captured image data is in digital format from the outset. This is the simplest way to evaluate, analyze, manipulate, and / or process the image data. The image data can be stored in a data storage device. Furthermore, the image data can be easily accessed from the data storage device. Alternatively, the image data can be stored in the control unit of the quality management monitoring system. In this case, the image data can be accessed directly.

[0037] According to an alternative embodiment of the present invention, the image data can be in a non-digital, for example analog, format. In this case, the image data is converted into digital form. For example, colors can first be calculated in shades of gray to which digital values ​​have previously been assigned, and then digitally analyzed.

[0038] The digital optical recognition device preferably comprises an optical device and a device for electronically evaluating the objects observed or detected by the optical device. The digital optical recognition device further preferably comprises a device for detecting a surface of the product to be cooked or already cooked and / or a cooking surface of the cooking appliance. In particular, within the scope of the invention, any surface that is an integral part of the cooking appliance is to be understood as a cooking surface of the cooking appliance. The cooking surface of the cooking appliance can include an inner wall of the cooking chamber, an inner door surface, a grill surface, a conveyor belt or the inner walls of a continuous oven, the walls of cooking vessels or kettles, the outer edges and / or inner surfaces of a deep fryer, and / or a surface of any component of the cooking appliance.

[0039] Furthermore, the quality management monitoring system can comprise a digital optical detection device directed at and monitoring the surfaces of the product being cooked and / or the cooked product and / or the cooking appliance; a control unit for operating the cooking program or cycle of the cooking appliance and the quality management monitoring system; and a collection of images of the surfaces of the product being cooked and / or the cooked product and / or the surfaces of the cooking appliance, which are stored in the control unit or in another storage medium. The optical detection device can preferably be arranged in or on the cooking chamber of the cooking appliance, or close to the cooking appliance, and configured to capture images of the product being cooked or the cooked product as the cooked product leaves the cooking chamber of the cooking appliance.Alternatively or additionally, the optical recognition device is configured to capture images of one or more selected areas inside the cooking appliance or other surfaces of the cooking appliance. The images can preferably be captured either continuously or at predetermined time intervals. The quality management monitoring system can further preferably issue a command or instruction so that the monitoring system is switched off and the current cooking cycle or cooking program can be terminated.

[0040] The quality management monitoring system can preferably also include an integrated delay time for the command or instruction described above for switching off the monitoring device. This allows the system, in addition to determining whether the cooking appliance needs cleaning, to also recognize that a cooking program or cycle has a limited remaining runtime until its end, so that cleaning can only take place after the cooking program or cycle has finished. More preferably, the quality management monitoring system can include an anticipatory or predictive aspect, allowing it to detect the degree of soiling of the cooking appliance and compare this degree of soiling with the next anticipated cooking process. If, during the next anticipated cooking program or cycle, the degree of soiling is significantly lower than expected, the system can then adjust the cleaning schedule accordingly.If, during a cooking cycle, it is likely that the degree of soiling of the cooking appliance will exceed acceptable levels of soiling and / or the acceptable quality level of the cooked product, the quality management monitoring system may preferably suggest or require cleaning of the cooking appliance before the start of the next anticipated cooking program or cycle. Advantageously, the quality management monitoring system may include a warning indicator to alert the operator of the cooking appliance that cleaning is necessary and / or that a cooking program or cycle has ended and / or should not begin. Preferably, the quality management monitoring system includes stored cleaning programs, the application of which may depend on the degree and / or type of soiling of the cooking appliance.Based on the specific degree and / or type of contamination, the quality management monitoring system can suggest a specific cleaning program and / or cleaning agent.

[0041] The quality management monitoring system and the procedure for determining when the cooking appliance needs cleaning can preferably be manually overridden by the operator. This is done by switching on the appliance after it has been switched off, when the quality of the product being cooked or already cooked indicates a need for cleaning when compared to the standard quality criteria and reference images, and / or when the cooking surface is determined to be so dirty that cleaning is necessary. Upon completion of the next cooking process after the override, the operation of the cooking appliance is automatically interrupted again until it is cleaned.

[0042] The optical detection device, in particular the digital optical detection device, either on its own or in a housing-mounted state, is preferably adjustable and / or configured to move or rotate during operation so that images of the food being cooked and / or the cooking surfaces of the cooking appliance can be captured from different angles or perspectives. A programmable control unit may be provided for this purpose, configured to move the digital optical detection device in a coordinated manner synchronized with the cooking programs or recipes. The programmable control unit may preferably be the control unit of the quality management monitoring system.

[0043] Advantageously, the quality management monitoring system uses real-time, first-hand information about the contamination level of the surface of the product being cooked or cooked, and / or the cooking surface of the cooking appliance, and / or the internal environment of the cooking appliance to determine the need for cleaning the cooking surface or the internal environment of the cooking appliance, thus maintaining the quality of the cooked or to-be-cooked products.

[0044] Within the scope of the present invention, the term "image" can refer to a single image or a sequence of images, such as a video.

[0045] The optical detection device is in signal communication with a control unit that has access to image data, i.e., image or video recordings of surfaces of the product being cooked or already cooked and / or cooking surfaces of the cooking appliance. Preferably, the control unit can be designed as part of the optical detection device. Furthermore, the control unit can preferably also have additional functions. The control unit has access to the image data, i.e., the digital data, the images of the surfaces of the product being cooked or already cooked and / or the cooking chamber, or everything that is calculated from the captured images of the surfaces of the product being cooked or already cooked and / or the cooking surface of the interior or other surfaces of the cooking appliance or components of the cooking appliance, such as a conveyor belt of a continuous oven. Alternatively, an analog optical detection device can also be used.

[0046] The optical detection device can preferably be arranged in or on the cooking chamber or on other surfaces of the cooking appliance or its components. Preferably, the optical detection device is configured such that all products to be cooked or already cooked, and / or at least those cooking surfaces most likely to become soiled, are within the field of view of the optical detection device.

[0047] The cooking surfaces that typically become soiled in various cooking appliances are the inner walls and / or an inner door surface of the cooking appliance, a grill surface, the inner walls or a conveyor belt of a continuous oven, an inner frying pot of a deep fryer, or the inner walls of cooking vessels or kettles.

[0048] From its position in, on, or near the cooking appliance, the optical detection device provides a reliable view of each product being cooked or already cooked within the appliance. For cases where the same or similar products are cooked in the appliance, a single optical detection device is preferably provided in the quality management monitoring system and / or commercial cooking appliance. This is particularly advantageous when the same or similar products are cooked in a discontinuous or batch cooking process. A single optical detection device can also preferably be used in cases where the products are cooked in a continuous cooking process.However, since in continuous cooking processes the products are usually loaded into and removed from the cooking appliance at different times, a plurality of optical detection devices can preferably be provided. This allows the different products to be observed simultaneously, in particular by separate optical detection devices.

[0049] In a continuous cooking process, however, it is more efficient and simpler if only the cooking surface of the appliance is monitored by the optical detection device, so that, in particular, only the degree of soiling of the cooking surface is determined. The reason for this is that in a continuous cooking process, the products being cooked in the appliance are constantly changing, which means that the different surface areas of the products monitored by the optical detection device are not constant.

[0050] The features described above with regard to the optical detection device apply to any optical detection device if more than one optical detection device is provided in the quality management monitoring system and / or the cooking appliance.

[0051] The commercial cooking appliance can preferably be designed as a combi steamer. A combi steamer is a cooking appliance used for cooking with hot air, steam, or superheated steam, or combinations of these cooking methods. The combi steamer preferably comprises at least one cooking chamber, a door that can be opened and closed to allow or restrict access to the cooking chamber, a steam generator, a fan, a heating element for heating the cooking chamber, and a control unit with a user interface. The user interface may include a display.

[0052] Other commercial cooking appliances in which the quality management monitoring system according to the invention can be used and in which the method according to the invention can be applied include convection ovens, conveyor ovens, collapsible grills, cooking vessels, fryers, kettles, ovens, microwave ovens, or convection ovens. Each of these cooking appliances has at least one cooking surface that can become soiled, which can impair the quality of the products being cooked or already cooked.

[0053] For example, in a convection oven that includes a cavity-shaped cooking chamber, the ceiling, floor, side walls, and inner door surface will become soiled. This soiling can manifest as browning, graying, and / or blackening of these surfaces.

[0054] Different degrees of browning can indicate protein and / or fat contamination of varying severity. Different degrees of graying can indicate the formation of a salt coating and / or limescale deposits on components of the cooking appliance. Different degrees of blackening can indicate the use of a smoke generator. Based on the specific degree and / or type of soiling on the cooking surfaces, the most effective and efficient automatic cleaning method can be recommended.

[0055] With a folding grill, the grilling surface typically becomes dirty and / or sticky. An increase in the number of dark spots, black pigments, or deposits on the grilling surface leaves unsightly stains on the food being cooked, indicating an accumulation of dirt and / or unwanted deposits on the grilling surface.

[0056] In a continuous oven, the inner walls of the oven or the conveyor belt become contaminated with fats that can fall onto or into the food being cooked. This impairs the appearance and taste of the food. Furthermore, it can cause a flare-up inside the oven, which can not only scorch the food but also damage the oven itself.

[0057] Based on the level of soiling, the quality management monitoring system can suggest any number of cleaning processes. These include, for example, simple brush cleaning, manual cleaning with any cleaning agent, an automatic cleaning cycle using detergents or descaling agents, etc. Additionally, the quality management monitoring system can interrupt the operation of the cooking appliance to ensure optimal cooking results and to prevent potential health problems and / or damage to the appliance.

[0058] The cooking appliance may have preset quality parameters that can be detected by the quality management monitoring system and / or an installed program, whereby the installed program operates in conjunction with the quality management monitoring system and / or controls the quality management monitoring system. The quality management monitoring system and / or the program may also allow the operator of the cooking appliance to modify the preset parameters in order to set modified or new parameters and / or add new images or parameters, and / or override the preset parameters or the operation of the quality management monitoring system, so that the cooking program or cooking cycle is interrupted if the detected contamination level or the detected quality of the cooked product meets the preset, modified, or new parameters.Overriding the preset parameters or overriding the operation of the quality management monitoring system may be desirable in cases where the cooking process is nearly complete, for example, when only one minute of cooking time remains. In such cases, interrupting the cooking cycle or the cooking program altogether would offer a slight advantage for the operation of the cooking appliance and would not noticeably impair the quality of the cooked product. Furthermore, the ability to override the preset parameters or override the operation of the quality management monitoring system would be helpful in cases where the operator of the cooking appliance decides to continue operation regardless of the specific cleaning requirements. In this case, the operator can manually override the stopped state of the cooking appliance.

[0059] It should be noted that all the features, functions and advantages described above relate to both the method and the quality management monitoring system or the cooking appliance according to the present invention.

[0060] Further details, advantages and features of the present invention will become apparent from the following description of a preferred embodiment with reference to the drawing. It shows: Fig. 1 a highly simplified, schematic front view of an embodiment of a cooking appliance according to the invention with a quality management monitoring system; Fig. 2A, B a process flow diagram of the quality management monitoring system, by means of which the procedure according to the preferred embodiment is explained; and Fig. 3 a schematic representation of the quality management monitoring system of Fig. 1. Description of the embodiments

[0061] Fig. Figure 1 shows a front view of a schematically simplified representation of a commercial cooking appliance 1 according to a preferred embodiment of the invention, in which a quality management monitoring system 10 is used. The cooking appliance 1 is preferably a combi steamer. Alternatively, the cooking appliance 1 can be an oven, a microwave oven, a grill, a deep fryer, or a cooking vessel. The quality management monitoring system 10 is specifically designed as a dynamic optical quality management system (DOQM system).

[0062] The cooking appliance 1 preferably comprises a housing 2 with a cooking chamber 3. Access to the cooking chamber 3 is provided by a door 4, which can be opened and closed. The cooking appliance 1 further comprises an optical recognition device 5, which is preferably designed as a digital optical recognition device (DORD).

[0063] From the Fig. As can be seen from Figure 1, the optical detection device 5 is preferably positioned within the cooking chamber 3 at or near an upper area of ​​the cooking appliance 1. However, the optical detection device 5 can be arranged arbitrarily in, on, or near the cooking chamber 3, as long as a clear view of at least one cooking surface or a product to be cooked or cooked is ensured by the optical detection device 5. The cooking appliance 1 also includes a user interface 6 (user interface). Fig. Figure 1 shows the cooking appliance 1 with a single digital optical detection device 5. Alternatively, several optical detection devices 5 can be provided. Furthermore, the cooking appliance 1 has a control unit 7, which, as shown in Figure 1, Fig. Figure 1 schematically shows the control unit 7, which is in signal communication with the user interface 6. It should be noted that in this embodiment, the control unit 7 is arranged inside the cooking appliance 1 and is not visible from the outside.

[0064] During the cooking process of the cooking appliance 1, the optical recognition device 5 is preferably configured to continuously capture one or more images of the product being cooked or the cooked product and / or a cooking surface of the cooking chamber 3. Alternatively, the images can be captured at time intervals.

[0065] It is expected that the surfaces of which images are captured may change during a cooking program or cooking cycle. For this purpose, the optical recognition device 5 is further designed to be automatically rotatable and / or adjustable. Thus, for example, images of different surfaces of the food being cooked or cooking surfaces of the cooking appliance 1 can be captured alternately during the cooking process. The captured images are then compared with reference images of the food being cooked, which indicate the need to clean the cooking surfaces, and / or reference images of dirty cooking surfaces requiring cleaning. The captured images can preferably be stored in a first memory 7a of the control unit 7 and the reference images in a second memory 7b of the control unit 7. Alternatively or additionally, the captured images and / or the reference images can be stored in a separate storage device or...stored in a separate memory 8, which is in signal communication with the control unit 7.

[0066] The optical detection device 5 is activated at the start of a cooking program or cycle. This can occur, for example, either automatically by switching on the cooking appliance 1 or by the control unit 7. The optical detection device 5 begins to capture images of the food being cooked and / or one or more cooking surfaces of the cooking chamber 3. Data that can be extracted from the captured images and used to dynamically determine the degree of soiling of the cooking surface(s) of the cooking chamber 3 can also be stored in the first memory 7a of the control unit 7 or in the separate memory 8. Preferably, the optical detection device 5 is arranged, for example, on a guide rail or a similar device. The optical detection device 5 is configured to move up and down within the cooking chamber 3.Thus, the optical recognition device 5 can capture images of different areas of the same cooking product and / or of different cooking products. This can be particularly advantageous when different cooking products are cooked simultaneously in a continuous cooking process (rolling-type cooking process). The optical recognition device 5 can preferably also be configured to move along the guide rail or similar structure to position itself next to the respective cooking product. The ability of the optical recognition device 5 to move within the cooking chamber 3 is particularly advantageous in cooking appliances with multiple cooking levels on which the same or different cooking products can be cooked.

[0067] Furthermore, the cooking appliance 1 can be equipped with a lighting device configured to illuminate the product being cooked or already cooked and / or a cooking surface of the cooking chamber 3 during image capture. The optical detection device 5 is, for example, an optical device with a main lens, the main lens preferably having a small aperture to provide a high depth of field.

[0068] The following refers to the Fig. 2A and Fig. 2B a method according to the embodiment of the present invention is described in detail.

[0069] In Fig. Figure 2A illustrates the interactions between an operator of the cooking appliance 1 and the quality management monitoring system 10 with the cooking appliance 1. In general, the procedure comprises the following steps.

[0070] In step 20, the operator switches on the cooking appliance 1. After switching on the cooking appliance 1, in step 21, its controls are also switched on. In step 22, the quality management monitoring system is activated. Steps 21 and 22 can either be performed automatically as a consequence of step 20 or be separate actions performed manually by the operator of the cooking appliance 1. To avoid potential errors and reduce the number of steps to be performed by the operator, steps 21 and 22 are performed automatically as a consequence of step 20. In step 23, a cooking program or recipe is entered, either automatically or manually.When entering a cooking program or recipe, information such as the type of cooking program and details like temperature, cooking time, steaming time control, holding times, and end times are preferably provided to the quality management monitoring system. This is indicated by the double arrow between steps 22 and 23. The term "type" of cooking program refers to whether it is a continuous / rolling-type cooking program or a discontinuous / batch-type cooking program.

[0071] Step 24 is a decision point or decision block. The question asked is whether there is enough time to complete the entered cooking program or recipe before the cooking appliance needs cleaning. If the answer is "No," the process continues to step 29 and a warning signal is issued. If the answer is "Yes," the cooking program is started and the process proceeds to step 25. Step 24 is optional, however. This means that step 24 either does not exist or can be omitted. In this case, the quality management monitoring system continues to step 25.

[0072] In step 25, the optical detection device 5 is activated. After activation of the optical detection device 5, which preferably occurs automatically, the image focus of the optical detection device 5 is adjusted. This is achieved automatically, for example, by the control unit 7 or autofocus. It should be noted that the optical detection device 5 can be designed as an autofocus imaging device, so that a change in the field of view of the optical detection device 5 does not significantly change the quality of the captured images. The activation of the optical detection device 5 in step 25 is advantageously carried out by the quality management monitoring system. Depending on whether the cooking program is continuous or discontinuous, the quality management monitoring system can instruct the optical detection device 5 to capture images only of the cooking surfaces of the cooking appliance 1 or 2.to measure the inner surfaces of cooking chamber 3. It should be noted that determining the type of cooking program may not be possible with other cooking appliances.

[0073] In step 26, the optical recognition device 5 captures at least one image, preferably a plurality of images, of an area of ​​a product to be cooked or cooked and / or a cooking area of ​​the cooking chamber 3 during the operation of the cooking program. The captured images are stored in the first memory 7a of the control unit 7 or in the separate memory 8, which is in signal communication with the cooking appliance 1 and is electronically accessible via the control unit 7.

[0074] In step 27, the images of the cooking surface captured in step 26 are compared with reference images of the same or a similar cooking surface that indicate soiling. Alternatively or additionally, the images of the cooking surface captured in step 26 are compared with reference images of a soiled cooking surface requiring cleaning. Specifically, the captured images of the cooking surface are compared with the same cooking surface in a soiled state requiring cleaning.

[0075] The images captured by the optical recognition device 5 in step 26 are preferentially transferred to the control unit 7. The control unit 7 then compares the captured images with a database of pre-captured and pre-stored reference images, which are located in the first memory 7a of the control unit 7 or in separate memory 8. The database of previously captured reference images can be stored in the second memory 7b of the control unit 7, in separate memory 8, or in a memory that is integrated into the cooking appliance 1, but not necessarily in the control unit 7.

[0076] Furthermore, the pre-captured reference images can be selected from images of surfaces of pre-cooked products in the same cooking appliance 1, from a compilation of images of pre-cooked products in other cooking appliances at the same or a similar facility, or from a pool of images of cooking products. Alternatively, datasets, particularly datasets from the manufacturer of cooking appliance 1, can be loaded as reference images. The manufacturer can create datasets by testing publicly available or special cooking products. For example, a fast-food chain could send a special product, which is available or will soon be launched, to the manufacturer of cooking appliance 1. The manufacturer can then create images of the product in a laboratory.Alternatively, the operators of the cooking appliance or chefs can have their own cooking recipes or cooking programs with associated pictures of products to be cooked or already cooked in their own databases.

[0077] In step 28, based on the comparison made in step 27, another decision point is reached, asking whether cleaning is required. If the answer is "No," the procedure returns to step 26, and steps 26 and 27 are repeated until the food is cooked and the cooking program is complete. If the answer to the cleaning requirement is "Yes," the procedure proceeds to step 29, and a warning signal is issued. If the answer in step 28 is "Yes," the quality management monitoring system automatically deactivates cooking appliance 1, preventing further cooking until it has been cleaned.Optionally, in step 28, the quality management monitoring system can determine the remaining cooking time until the end of the current cooking process. The cooking appliance can initially terminate the current cooking process as long as there is no danger associated with operating the cooking appliance 1. Afterwards, the cooking appliance 1 can be automatically deactivated until it has been cleaned.

[0078] In step 29, the operator of the cooking appliance 1 can preferably cancel the cleaning requirement notification from step 28. When the cleaning requirement is canceled, this information can be stored as a reference (for example, for quality control or operator training) either in the control unit 7 or the quality management monitoring system 10. The time the cleaning requirement was canceled is displayed in step 30. Alternatively or additionally, step 30 can display a time until the appliance switches off, indicating a delay in performing a cleaning operation. It should be noted that in step 28, the quality management monitoring system can also determine the remaining cooking time of a cooking process. Therefore, the time displayed in step 30 can be the previously described time the cleaning requirement was canceled and / or the switch-off time.Step 31 ends cooking program 23. Steps 29 and 30 are optional.

[0079] It should also be noted that steps 26 and 27 are repeated if no cleaning is required in step 28. If a cooking program ends without requiring cleaning, the procedure proceeds to step 31. In this case, after the end of cooking program 23 according to step 32, another decision point is reached, asking whether cleaning is necessary. If the answer to this question is "No," the procedure returns to step 23. If step 24 is omitted or does not exist, the quality management monitoring system is then directed to step 25. At this point, a new cooking program will have been entered (step 23), and the control unit 7 and / or the quality management monitoring system will have access to: (1) the cooking time and other parameters of the new cooking program and (2) reference images or comparison image data regarding the degree of soiling of the cooking chamber (3) or of the food being cooked or already cooked.At this point, the control unit 7 and / or the quality management monitoring system determine whether there is enough time to complete the new cooking program before cleaning is required. The procedure then continues according to the steps described previously. If the answer to the question in step 32 is "Yes", the procedure preferably proceeds according to the [missing information]. Fig. Continue to 2B.

[0080] As from the Fig. As can be seen in Figure 2B, if the answer to the question in step 32 is positive, the procedure continues to step 33. In step 33, entering a new cooking program or recipe is prohibited, and the cooking appliance 1 is automatically stopped. At this point, the procedure continues to step 34. In step 34, the degree and type of soiling are determined. It should be noted that reference images showing different degrees and / or types of soiling are pre-stored in the control unit 7 and / or the separate memory 8.

[0081] In step 35, the degree and / or type of soiling determined in step 34 is compared with the reference images. Based on the result of this comparison, a suitable cleaning method or a range of suitable cleaning methods and / or cleaning products is determined. In step 36, the determined cleaning methods and / or cleaning products are displayed on user interface 6.

[0082] In step 37, the displayed cleaning method, or a selection of cleaning methods if multiple cleaning methods are displayed, is chosen. Alternatively, in step 37, the operator of the cooking appliance 1 can enter a different cleaning method or modify an existing, displayed cleaning method. In any case, each selected cleaning method is carried out in step 38. For this purpose, the cooking appliance 1 preferably has a cleaning device.

[0083] Step 39, which represents another decision point, asks whether the cleaning performed is sufficient. If the answer is "Yes," the process continues to step 23, allowing a new cooking program or recipe to be entered. If the answer is "No," the process returns to step 34, and steps 34 through 38 are repeated.

[0084] The following refers to the Fig. 3. The quality management monitoring system 10 of the cooking appliance 1 is described in detail. The quality management monitoring system 10 is set up to carry out the procedure described above.

[0085] The cooking appliance 1 of Fig. 3 is equipped with a main switch 11. To switch on the cooking appliance 1, the main switch 11 is activated, which in turn activates the control unit 7. The control unit 7 controls all cooking functions and parameters of a cooking process, such as the time and temperature of a cooking program and the regulation of steam. Furthermore, the control unit 7 can preferably activate the optical detection device 5. However, as already described above, the optical detection device 5 can also be activated manually. The optical detection device 5 is in signal communication with the control unit 7, which is indicated by the double arrow between the control unit 7 and the optical detection device 5 in Fig. 3 is symbolized. Furthermore, the optical recognition device 5 is configured to send information from the captured images to the control unit 7. This information can be stored in the control unit 7 or in the separate memory 8 ( Fig. 1) or stored in a database of the cooking appliance 1 for various purposes, as described below.

[0086] From the Fig. It follows from section 3 that the cooking appliance 1 includes a control unit 13, which is activated by the control device 7 to control the optical detection device 5 and a lighting device 14, if present. Alternatively, the control device 7 is configured to directly control the optical detection device 5 and the lighting device 14.

[0087] The control unit 7 also has access to pre-stored reference images of various food products to be cooked or already cooked, which indicate soiling of the cooking surface(s) of the cooking appliance. A comparator 15 of the control unit 7 and / or the control unit 13 compares these reference images with the images of the food products to be cooked or already cooked, which are detected by the optical recognition device 5. Under special circumstances, the control unit 13 also allows the cooking program to continue, even if otherwise a warning would have been issued or deactivation of the cooking program would have been recommended.

[0088] Furthermore, the control unit 13 manages the output of a warning signal to the operator of the cooking appliance 1, indicating that a new food item to be cooked should not be placed in the cooking chamber 3. The control unit 13 can be configured as part of the control device 7. In any case, the control device 7 is configured to perform the functions described above. While images of an area of ​​the food item and / or a cooking area of ​​the cooking chamber 3 are captured by the optical detection device 5, this information is forwarded to the control unit 13. This is symbolized by a double arrow between the control unit 13 and the optical detection device 5.

[0089] The decisions of controller 13 regarding issuing a warning, deactivating or continuing the cooking program or cycle, and issuing a warning not to place a new food item in cooking chamber 3, are transmitted to control unit 7 (indicated by the double arrow between controller 13 and control unit 7). The decisions made by controller 13 are then forwarded by control unit 7 to user interface 6.

[0090] The user interface 6 includes, for example, a touchscreen and / or a display for providing information to the operator and for the operator to input information. The user interface 6 and the control unit 7 interact with each other, as indicated by the double arrow between the user interface 6 and the control unit 7. This interaction is advantageous when, for example, the operator wants to override certain aspects of the operation of the cooking appliance 1, such as the detection of selected food items and / or whether the cooking program has been selected incorrectly. In these cases, the operator can select the food item and / or the cooking program. This information is then forwarded to the control unit 7 so that the appropriate cooking program is selected.

[0091] As can be seen from the preceding description, the quality management monitoring system 10 and the corresponding method according to the present invention allow continuous monitoring of a cooking process and provide the operator with several decision points at which the operator can input decisions / information, while simultaneously enabling automatic control of the cooking program. Since all information regarding the cooking programs and the operator's decisions / information is stored, the following can be easily determined: (1) the use and wear of the cooking appliance 1; (2) the type and number of cooked products; (3) and errors during the process.

[0092] In addition to the foregoing written description of the invention, explicit reference is hereby made to the graphic representation of the invention in the following for its supplementary disclosure. Fig. 1, Fig. 2 to Fig.3. Referenced. Reference symbol list 1 Commercial cooking appliance 2 cases 3 Cooking chamber 4-door 5 optical detection device / digital optical detection device 6 User interface 7 Control unit 7a first storage 7b second memory 8 separate storage 10 Quality Management Monitoring System 11 Main switches 13 Control 14 Lighting equipment / Lighting device 15 comparisons

Claims

[1] Method for determining the need to clean a commercial cooking appliance with at least one cooking surface, characterized by the steps: - Capturing at least one image of at least part of the cooking surface and / or at least part of a cooking product to be cooked or cooked by an optical recognition device, - Comparing the captured image of the cooking surface area with a pre-stored reference image of a dirty cooking surface requiring cleaning, and / or the captured image of the product to be cooked or cooked with a pre-stored reference image of the product in a state of cooking that indicates a need for cleaning the cooking surface, and - Decide, based on the result of the comparison, whether cleaning is necessary. [2] Method according to claim 1, wherein an ongoing cooking process is preferably automatically interrupted and / or the cooking appliance is switched off when a need to clean the cooking appliance is detected. [3] Method according to claim 2, wherein a remaining cooking time until the end of a current cooking process is compared with a predetermined time threshold, and the cooking appliance is only switched off after the remaining cooking time has elapsed if the remaining cooking time is less than the predetermined time threshold. [4] Method according to one of the preceding claims, wherein a current degree of contamination is calculated and / or a current contamination type is determined based on the captured image. [5] Method according to claim 4, wherein the degree and / or type of soiling expected in the next cooking process of the cooking surface is determined based on the current degree and / or type of soiling of the cooking surface, and / or a cooking time of the next cooking process and / or a cooking time remaining until the end of the current cooking process, and in particular it is proposed that the cooking surface be cleaned before the start of the next cooking process if the expected degree of soiling necessitates cleaning of the cooking surface. [6] Method of claim 4 or 5, wherein a cleaning program for cleaning the cooking surface is selected from pre-stored cleaning programs based on the current and / or expected degree of soiling, and / or the current and / or expected type of soiling. [7] Method according to one of the preceding claims, wherein a warning signal is given when the need to clean the cooking surface is detected. [8] Method according to any one of claims 2 to 7, wherein a switched-off state of the cooking appliance and / or an interrupted state of the cooking process and / or the emitted warning signal is overwritten and / or canceled when the cooking appliance is switched on again. [9] Method according to any of the preceding claims, wherein images of the cooking surface and / or the cooking product are captured continuously or at predetermined time intervals. [10] Commercial cooking appliance, - with at least one cooking surface and - with a quality management monitoring system (10) for carrying out a method according to any one of claims 1 to 9, comprising: - an optical detection device (5) directed at least towards a part of the cooking surface and / or at least a part of the product to be cooked or cooked; and - a control unit (7) which is in signal communication with the optical detection device (5) and comprises the following components: • a first memory (7a) for images of the part of the cooking surface and / or the part of the cooking product captured by the optical recognition device; • a second memory (7b) for reference images of a soiled cooking surface requiring cleaning, and / or for reference images of cooked products in a state of cooking that indicates a need for cleaning; and • a comparator (15) which is in signal communication with the first memory (7a) and the second memory (7b) for comparing the captured images with the reference images.

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