Cooking appliance with food recognition

Abstract

Cooking appliance (10) with a cooking chamber (12) in which several slots (E1, ... E9) are defined and a camera (30) which serves to detect at least one cooking parameter of food which is placed in one of the slots, characterized by a light guide (32) which extends between the camera (30) and the cooking chamber (12), wherein the light guide (32) has an optical interface (34) for each slot.

Description

[0001] The invention relates to a cooking appliance with a cooking chamber in which several slots are defined, and a camera that serves to detect at least one cooking parameter of food that is placed in one of the slots.

[0002] In the field of professional cooking equipment (for example, for restaurants, canteens, and large-scale catering), to which the invention relates, it is known to automatically monitor the cooking process by having a camera capture an image of the food being cooked in the cooking chamber. This image can then be evaluated from various perspectives, for example, for the purpose of food identification or for the purpose of recognizing the current cooking state (for example, the browning of the food).

[0003] To protect it from dirt and heat, the camera used is positioned outside the cooking chamber. For example, the camera can "look into" the cooking chamber through a viewing window located in the wall. A disadvantage of this method is the comparatively high effort required to monitor and analyze the many different compartments within a cooking appliance.

[0004] The object of the invention is to create a cooking appliance in which several trays can be monitored with minimal effort.

[0005] To solve this problem, the invention provides a light guide in a cooking appliance of the type mentioned above, which extends between the camera and the cooking chamber, the light guide having an optical interface for each insert. The basic idea of ​​the invention is to use a single camera that receives a composite image made up of the individual images from the individual inserts. These individual images are captured by the light guide and transmitted to the camera, which can therefore be located away from the cooking chamber and at a structurally suitable location on the cooking appliance.

[0006] In principle, it is possible to use rigid light guides such as prisms, etc. However, the light guide is preferably formed by a fiber optic cable. A fiber optic cable is characterized by its flexibility and can therefore be easily routed within the cooking appliance between the points where the light guide "exits" the cooking chamber and the camera.

[0007] Preferably, the optical fiber is formed by a large number of individual optical fibers, with a large number of optical fibers terminating at each optical interface. Bundling a large number of individual fibers ensures that the image transmitted to the camera has a sufficiently high resolution.

[0008] Preferably, the optical fibers assigned to a module are spatially separated at the end facing the camera. This facilitates the correct assignment and evaluation of the transmitted individual images to the respective modules. The optical fibers can, for example, be arranged in a grid.

[0009] Preferably, a control system is provided that can perform image recognition separately for each tray. For this purpose, the control system can predefine which section of the transmitted overall image is assigned to which tray. The control system can then evaluate the individual partial images according to desired criteria, for example, for the purpose of food identification or for recognizing cooking process parameters such as the degree of browning.

[0010] If desired, a lens can be assigned to the optical interface. This may improve the quality of the transmitted image.

[0011] It is also possible to assign a light source to the optical interface. This ensures, firstly, that a high-quality single image is available. It is also conceivable that the light source emits light with a specific wavelength, chosen to represent specific information that is well-suited to that wavelength, for example, outside the visible light spectrum.

[0012] According to one embodiment of the invention, a heater is provided for the optical interface. This ensures that no condensation can form there, thus guaranteeing good image transmission at all times.

[0013] Advantageous embodiments of the invention are set out in the dependent claims.

[0014] The invention is described below with reference to an embodiment illustrated in the accompanying drawings. These show: - Fig. 1 schematically a cooking appliance according to the invention; and - Fig. 2 schematically the end of the light guide assigned to the camera.

[0015] In Fig. Figure 1 shows a cooking appliance 10, which has a cooking chamber 12 in which several slots E are defined. For this purpose, guide rails 14 can be used, in which cooking accessories 16 are arranged. Food 18, shown schematically here, can be arranged on the cooking accessories 16. This food is cooked in the cooking chamber 12 under the influence of heat, which is transported into the cooking chamber 12, for example, by means of hot air or hot steam. For this purpose, heating elements 20 and a fan 22, shown schematically here, are provided.

[0016] The Cooking Unit 10 is a professional cooking appliance designed for use in restaurants, canteens, and large-scale catering establishments. It allows for the automated cooking of a wide variety of foods using different cooking programs. The appliance may incorporate a feature called "intelligence," meaning it automatically adapts the user-selected cooking program to the specific conditions. For example, if the Cooking Unit 10 detects that a smaller quantity of food than usual has been placed in the cooking chamber 12, it can automatically adjust the temperature or cooking time to achieve the desired doneness.

[0017] It is also known that the food being cooked inside the cooking chamber 12 is optically detected and / or monitored in order to automatically recognize, for example, the type of food being cooked in the cooking chamber or to monitor the progress of the cooking process by detecting and / or evaluating changes in size or surface of the food being cooked (e.g., browning).

[0018] For optical evaluation, the cooking appliance 10 has a camera 30 which receives individual images of a predefined area from inside the cooking chamber 12 via a fiber optic cable 32. The camera 30 can be based on any suitable image acquisition technology that allows for electronic image evaluation. For example, a CCD chip can be used. It can be positioned at any suitable location on or inside the cooking appliance, taking into account ambient temperatures, accessibility, etc. Since the fiber optic cable 32 is flexible, it can be easily routed and connected to the camera.

[0019] The light guide 32 has an optical interface 34 for each insert, which can be simplified as a "branch" through which the camera can "see" into the cooking chamber 12 at the corresponding point. The branches 34 extend, for example, through a cooking chamber wall 36 at a point slightly above the rail 14 of the corresponding insert. This allows an image to be taken of the corresponding insert and of the food 18 located on a cooking accessory 16 arranged therein.

[0020] The optical fiber 32 preferably consists of a plurality of individual optical fibers. At the camera-side end 38 it has the maximum number of individual optical fibers, and at each optical interface 34 a portion of optical fibers is led out of the optical fiber 32 and towards the corresponding optical interface 34, where these optical fibers then terminate.

[0021] In Fig.Figure 2 schematically shows the image transmitted at the camera-side end 38 of the optical fiber 32. The overall image transmitted across the cross-section of the optical fiber 32 is composed of several individual images, each assigned to a single module. In the illustrated embodiment, there are nine modules, so nine individual images are transmitted for modules E1 to E9. Within each individual image, the image of the module is transmitted by the corresponding number of individual optical fibers 40. The number of optical fibers used to transmit an individual image is high enough to ensure a sufficiently high level of accuracy for the transmitted image of the corresponding module.

[0022] Camera 30 is associated with a control unit 42, which evaluates the overall image transmitted by the optical fiber 32, separately for each tray. For this purpose, the control unit stores information about the section of the overall image in which the individual image assigned to a specific tray is located. This individual image can then be evaluated with regard to the cooking parameter(s) of interest. For example, the type of food in the corresponding tray can be determined from its shape and size, and caliber identification is also possible. The progress of the cooking process can be inferred from the color of the food's surface.

Claims

[1] Cooking appliance (10) with a cooking chamber (12) in which several trays (E1, ... E9) are defined and a camera (30) which serves to detect at least one cooking parameter of food which is placed in one of the trays, characterized by a light guide (32) extending between the camera (30) and the cooking chamber (12), wherein the light guide (32) has an optical interface (34) for each slot. [2] Cooking appliance according to claim 1, characterized by , that the optical fiber is formed by an optical fiber cable (32). [3] Cooking appliance according to claim 1 or claim 2, characterized by , that the optical fiber (32) is formed by a large number of individual optical fibers, with a large number of optical fibers terminating at each optical interface (34). [4] Cooking appliance according to claim 3, characterized by, that the optical fibers (32) assigned to an insert (E1, ... E9) are spatially separated at the end (38) facing the camera (30). [5] Cooking appliance according to any one of the preceding claims, characterized by , that a controller (42) is provided which can perform image recognition separately for each slot. [6] Cooking appliance according to any one of the preceding claims, characterized by , that a lens is assigned to the optical interface (34). [7] Cooking appliance according to any one of the preceding claims, characterized by , that a light source is assigned to the optical interface (34). [8] Cooking appliance according to any one of the preceding claims, characterized by , that a heater is assigned to the optical interface (34).

Images