METHOD FOR COOLING THE ESCAPING VAPOR OR STEAM FROM THE COOKING CHAMBER OF A COOKING APPLIANCE AND COOKING APPLIANCE

Description

[0001] The invention relates to a method for cooling the vapors or steam escaping from the cooking chamber of a cooking appliance, in particular an oven or steam cooker. The cooking appliance is equipped with a cooking chamber, a door for closing a front loading opening of the cooking chamber, a cooling device for replacing part of the vapors or steam in the cooking chamber with cold air, and a control device for actuating the cooling device in response to a control command. The invention also relates to a cooking appliance for carrying out such a method.

[0002] When cooking appliances heat food, hot vapors are created. These vapors are formed from the moisture present in the food at the beginning, which is then released into the outside environment as the cooking progresses. There are also cooking appliances in which steam is introduced into the cooking chamber to heat it or support the cooking process. Such cooking appliances are primarily ovens or steam cookers, but there are also combination appliances that use a combination of steam, radiant heat and dielectric heating via microwaves. If the door of one of the aforementioned appliances is opened manually by an operator during the cooking process, the vapors or steam present in the cooking chamber can suddenly escape from the loading opening, which has been at least partially exposed. This can startle the operator or cause problems such as fogging up glasses.For the sake of simplicity, the term steam is used in the following description, even though vapors could be meant.

[0003] As is well known, hot steam can transfer a very large amount of energy, and water is the element or substance found in everyday life with one of the highest energy densities or heat capacities. When applied directly to a person's skin, this can be unpleasant. Not only with regard to the well-being and safety of aspiring or already established amateur and professional cooks, but also to avoid side effects associated with steam in kitchens or similar rooms (temperature and steam exposure of neighboring appliances and furniture, undesirable moisture and condensation effects or deposits), it is advisable to prevent the occurrence of steam as much as possible in all conceivable situations, especially when doors are opened by the user.

[0004] To reduce the sudden escape of steam, it is known, for example, from EP 2 180 259 A1 to provide a deflection device in an oven with a cooling air outlet above the cooking chamber door. This deflection device pivots into the air flow into the cooling air outlet when the door is opened, thereby deflecting the air parallel to the loading opening and thus forming an air curtain that prevents steam from escaping from the opening. Similar devices are known from US 2017 0 082 296 A1 and EP 3 450 857 A2.

[0005] It is also known that during a cooking process a portion of the steam in the cooking chamber can be continuously removed and replaced with cold air. For this purpose, an opening is usually provided in the ceiling to connect the cooking chamber to the intake side of a cooling fan above. The cooling fan also draws in cold air from the area surrounding the cooking appliance and mixes the steam from the cooking chamber with the cold air. The proportion of cold air is usually greater than the proportion of steam due to the design of the fan and the air ducts, so that the mixed air generated by the cooling fan is still relatively cold. The mixed air is first passed over electrical and electronic components to cool them and then blown out of the front of the appliance via a flow line.Leaks in the cooking chamber near the door, the circulating air fan, or the lighting also draw in cold air from the outside of the appliance, which replaces the steam escaping from the opening in the ceiling. However, the exchange through the opening during a standard cooking program is generally minimal and does not lead to a significant reduction in the steam in the cooking chamber. DE 10 2016 121 834 A1 discloses varying the size of the opening between the cooking chamber and the flow line using a movable closure element. Furthermore, it is known to carry out a program-controlled so-called rapid cooling process at the end of or during a cooking program. In this process, a similar closure element is completely removed from the opening and / or the door is opened at least partially; see DE 10 2010 061 339 A1.

[0006] DE 10 2018 104 297 A1 describes a household appliance in which an infrared transmitter and an infrared detector form a proximity sensor that is capable of detecting a person approaching the appliance.

[0007] A cooking appliance of this type is known from document EP 3 647 664 A1. KR20190001887A also discloses a similar cooking appliance from the prior art.

[0008] The invention therefore addresses the problem of disclosing a method of the type mentioned above and a cooking appliance for carrying out such a method, in which the escape of steam from the loading opening is further reduced when the door is opened. According to the invention, this problem is solved by a method having the features of patent claim 1 and by a cooking appliance having the features of claim 12.

[0009] Advantageous embodiments and further developments of the invention emerge from the respective following subclaims.

[0010] The advantages of the invention are achieved in a method for cooling the escaping steam from the cooking chamber of a cooking appliance, in particular an oven or steam cooker, wherein the cooking appliance is equipped with a cooking chamber, a door for closing a front loading opening of the cooking chamber, a cooling device for replacing part of the steam in the cooking chamber with cold air and with a control device for actuating the cooling device by a control command, in that the control command is triggered by the signal or measured value of a proximity sensor arranged on the cooking appliance, wherein the signal or measured value is generated by the proximity sensor as a result of a person approaching the cooking appliance. Cooling the escaping steam, within the meaning of the invention, means replacing part of the cooking chamber atmosphere with cold air before or at the latest when the door is opened.In spatial terms, the loading opening is the area formed by the front edges of the cooking chamber and is free of any cooking chamber walls. The use of the proximity sensor, which triggers the control command and thus starts the cooling device, gives the appliance, in particular its electromechanical components, sufficient time and opportunity to move into a position in which a significant proportion of the cooking chamber atmosphere is exchanged for cold air before or at the latest when a person as operator manually opens the door. This can prevent a gush of steam from escaping from the loading opening. The proximity sensor or the control device can be suitable and designed to distinguish between an approaching person and a moving object or an approaching animal.It is even known from the prior art to identify certain people as operators through suitable image capture and analysis, for example, through gesture recognition, and to distinguish them from others who happen to be in the area where the device is installed. If such an identification device is not present on the device in question, the control system initially assumes that each person approaching is an operator and triggers the control command to activate the cooling device.

[0011] For this purpose, the invention provides that the following method steps are carried out either individually or at least partially in combination with one another: A. Increasing the exhaust airflow of a cooling fan, wherein the airflow entrains a portion of the vapors or steam from the cooking chamber via a first opening in the ceiling of the cooking chamber and transports them out of the cooking appliance via a flow line; C. Enlarging the first opening in the ceiling by moving an adjustable first flap unit; D. Opening a second opening in one of the cooking chamber walls by moving an adjustable second flap unit;

[0012] Advantageous embodiments of the cooling device result from the fact that the following process steps are carried out either individually or at least partially in combination with one another: B. Generating an intake air flow through the cooling fan or another fan, wherein the intake air flow is drawn in via a flow line through the cooling fan or the other fan, and wherein the flow line extends at least from the cooling fan or the other fan to an exhaust / intake opening in the front of the cooking appliance above the cooking chamber; E. Opening the door in a gap by an automatic opening device; To A.

[0013] By increasing the exhaust airflow, the amount of steam drawn out of the cooking chamber through the first opening is significantly increased. The resulting negative pressure ensures that cold air is drawn in through other openings, initially through existing openings or leaks in the cooking chamber, and then further amplified by the door being manually opened by an operator. The cooking chamber atmosphere is consequently cooled, and the resulting suction effect also reduces the escape of steam from the door gap created and enlarged by the opening. This increase is advantageously achieved by increasing the fan speed via the control device. Alternatively, a second cooling fan can be used, which the control device then switches on when a person approaches.Increasing the exhaust air flow also facilitates the use of a deflection device known from the prior art, for example a pivotable strip arranged in the area of ​​the exhaust / intake opening, which in a first position releases the exhaust air flow from the exhaust / intake opening at least approximately in the direction of the flow line and in a second position deflects the exhaust air flow towards the loading opening. This creates a very dense air curtain that even better prevents steam from escaping from the loading opening. In such an embodiment, it is particularly advantageous if at least one part of the strip projects into the pivoting range of at least part of the door, so that the strip is in the first position when the door is closed and in the second position when the door is open.This means that the air curtain is automatically generated by swinging the bar down, without the need for any additional adjustment devices. To B.

[0014] The intake airflow ensures that the steam escaping from the cooking chamber through the door gap, which increases as the door is opened, is directed away from the operator into the air flow duct. The cooking chamber atmosphere is then quickly permeated with cold air and cooled down. Because the fan's suction function is activated when a person approaches - either by reversing the direction of rotation of the cooling fan or by switching on another fan and, if necessary, switching the cooling fan off - a sufficiently strong suction effect can be built up when the door is opened. Advantageously, a air flow duct is provided that extends at least from the cooling fan or the other fan to an exhaust and / or intake opening in the front of the cooking appliance above the cooking chamber. This ensures that the steam is sucked in at the point it reaches first after the door is opened. The effect of the fan is greatest at this point.The intake air flow can advantageously be generated by the control device reversing the direction of rotation of the cooling fan. In this case, no additional fan needs to be used. Alternatively, the use of an additional fan is of course possible. In particular, this additional fan can also be used to extract cooking fumes that arise in the area of ​​a hob that is located above the cooking chamber, i.e. in the upper area of ​​the cooking appliance. In such a case, it is particularly advantageous if there is an additional flow line between the hob and the additional fan and if a switching device actuated by the control device is suitable and designed to establish a flow connection between the additional fan and optionally the additional flow line or the flow line.In this way, it is possible to switch between extracting cooking fumes from the hob and extracting steam from the cooking chamber. To C.

[0015] Enlarging the first opening in the ceiling alone leads to a cooling of the cooking chamber atmosphere because, according to the laws of physics, hot steam rises within the cooking chamber and escapes through the opening. As already described under A., ​​cold air is drawn into the cooking chamber, supporting atmospheric exchange when the door is opened. This effect is further enhanced by a combination with one of the measures described under A. or B., which then creates additional suction at the enlarged first opening. The first flap unit can, for example, be constructed as described in DE 10 2016 121 834 A1.In this embodiment of the invention, it is also advantageous if a flow line is arranged above the cooking chamber, extending to an exhaust and / or intake opening in the front of the cooking appliance above the cooking chamber, and if the opening in the ceiling fluidically connects the cooking chamber to the flow line. Either in the flow line or in a cooling fan (see A.), the steam escaping from the cooking chamber can then be mixed with cold air, preventing it from escaping uncooled elsewhere in the appliance. To D.

[0016] The term “cooking chamber wall” refers to a wall of the cooking chamber that is not the ceiling, i.e. the wall at the top during operation. The cooking chamber wall can be the floor, one of the side walls and preferably the rear wall of the cooking chamber. By providing and exposing an opening in one of the cooking chamber walls, various options for cooling the cooking chamber atmosphere are created. If no further openings are provided, steam can escape due to the excess pressure that arises during heating. If, as described under A. or C., further openings are provided and steam flows out of the cooking chamber through these openings, the second opening can be used to improve the supply of cold air and thus to cool the cooking chamber atmosphere more quickly. Both flap units can advantageously be moved, i.e. opened and / or closed, by actuators operated by the control device.It is particularly advantageous if the control unit and the second flap device are configured to open the second opening within a period of less than 5 seconds, in particular less than 3 seconds, and in particular a maximum of only 1 second. This enables rapid cooling. It is particularly advantageous if, when the second opening is opened via the control device, the latter switches on a recirculation fan to circulate the air or steam in the cooking chamber. This improves the mixing of the cooking chamber atmosphere with cold air. To E.

[0017] A very simple way of cooling the steam in the cooking chamber before an operator opens the door is to have the door slightly open before the operator actually opens it. This way, some of the hot steam has already escaped before the door is fully opened and this part has been replaced by cold air. The gap-wise opening is carried out by an automatic opening device that is activated by the control device when a person approaches. In this embodiment, it is particularly advantageous if the control device closes the door completely again by means of an automatic closing device if the door opening sensor does not detect any opening of the door beyond a gap within a predetermined period of time after the control command has been triggered by the signal or measured value of the proximity sensor.The opening and closing devices can advantageously be integrated into a common mechanism, but they can also be designed as separate components. The aforementioned reaction of the control device and the closing device ensures that the slightly open door is automatically closed again if a person approaches the cooking appliance only accidentally or without the intention of opening it. This prevents the cooking program from continuing with the door slightly open.

[0018] For all variants: In a particularly advantageous embodiment of the method, the cooling device is only activated in response to a control command from the control device in a cooking program if an operator has previously given permission when switching on the cooking program or during the course of the program via a control device on the cooking appliance. In this way, the operator can select that the cooling device is only activated in programs in which the door is intended to be opened during the program run. In a very simple embodiment, the proximity sensor is switched on by the operator's permission. In programs in which the proximity sensor is also used for other purposes, non-release can be implemented by suppressing the triggering of the control command to activate the cooling device.

[0019] As described under E., it is also advantageous for the other versions of cooling devices if the control device deactivates the cooling device if a door opening sensor does not detect any opening of the door beyond a gap within a predetermined period of time after the control command has been triggered by the signal or the measured value of the proximity sensor.

[0020] A cooking appliance for carrying out one of the above-described embodiments of a method according to the invention, in particular an oven or a steam cooker, is equipped with a cooking chamber, with a door for closing a front loading opening of the cooking chamber, with a cooling device for replacing part of the steam in the cooking chamber with cold air, with a control device for actuating the cooling device in response to a control command, and with a proximity sensor for generating a signal or a measured value as a result of a person approaching the cooking appliance. The control device of the cooking appliance is suitable and configured to execute the control command for carrying out one of the above-described embodiments of the method. Further advantageous embodiments of the cooking appliance are also described above in connection with the embodiments of the method.

[0021] An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows Figure 1 shows a perspective view of a built-in oven 11; Figures 2a to c show schematic sketches of first embodiments of a built-in oven 11 according to the invention; Figures 3a to c show schematic sketches of the first flap unit in various states; Figure 4 shows a block diagram of the function of a cooling device according to the invention; Figures 5a, b show schematic sketches of a part of a built-in oven 11 in a second embodiment (not according to the invention); Figure 6a show schematic sketches of a third embodiment of a built-in oven 11 according to the invention; Figures 6b, c show a second flap unit 331 of this embodiment; Figures 7a, b show schematic sketches of fourth embodiments of a built-in oven 11 according to the invention. 1. First embodiments

[0022] <h2 style=";text-align:left;direction:ltr">Figure 1shows a perspective view of a cooking appliance 10 according to the invention in the form of a built-in oven 11. This has a cooking chamber 30 (not visible in this figure) with a front loading opening 36 (also not visible here) (see for example the <h2 style=";text-align:left;direction:ltr"> Figure 2a , b). The loading opening 36 is closed by a door 40. Above the door 40, a control panel 70 can be seen, in which display devices 71, here a display 710, and control devices 72, here a push button 720, are arranged. Of course, the display and control devices 71 and 72 can also be combined to form a touch display, unlike shown in the figure. Between the upper edge of the door 40 and the lower edge of the control panel 70 extends a slit-shaped exhaust and / or intake opening 83, the function of which will be explained later. In the enlarged illustration A, a proximity sensor 73 can be seen, which in the embodiment shown here is arranged below the display 710. Of course, the sensor 73 can also be installed at another location on the device 10, but an arrangement in the control panel 70 is advantageous. The function of the sensor 73 will also be explained later. Furthermore, the <h2 style=";text-align:left;direction:ltr"> Figure 1parts of a door lock 44 can be seen.

[0023] <h2 style=";text-align:left;direction:ltr"> Figure 2a to c show schematic sketches illustrating the inventive functions of the built-in oven 11 from <h2 style=";text-align:left;direction:ltr"> Figure 1 be explained in detail. The oven 11 has a housing 13, which, as already described in connection with <h2 style=";text-align:left;direction:ltr"> Figure 1explains a cooking chamber 30 that is open at the front. The cooking chamber is delimited by walls, namely a ceiling 31, a floor 32, a rear wall 33, and two side walls 34 and 35. A top heat element 371 and a ring heater 372 are arranged in the cooking chamber 30 for heating, and a bottom heat element 376 is also provided beneath the floor 32. The heat from the ring heater 372 can be better distributed in the cooking chamber 30 via a circulating air fan 373 and, if necessary, via a shielding plate 374 with openings 375. Additional heating devices 37, such as a microwave heater or a steam generator, are not shown in the drawings, but can be provided in addition to the pure radiant heaters 371, 372, and 376. However, a cooking appliance 10 according to the invention can also be operated as a microwave oven or as a steamer other than in the oven function described above.In this case, too, radiant heaters 371, 372 and 376 can be used additionally, but the use of the individual heating devices 37 (top heat, bottom heat, circulating air heating, microwave, steam) in the programs of these appliances 10 will be different than in the built-in oven 11 described. As already described above, the loading opening 36, which is formed by the open side of the cooking chamber 30, can be closed by a door 40. The . <h2 style=";text-align:left;direction:ltr"> Figure 2a to cshow a device 10 in which the door 40 is designed to be pivotable about a horizontal axis in the region of the lower edge 401. To hold the door 40 in the closed state, and if necessary also to lock the door 40 in a state in which opening it is dangerous for an operator and therefore not permitted (for example when carrying out a pyrolysis cleaning program), corresponding parts of a door lock 44 are provided in the upper region 402 of the door 40 and in the adjacent region of the housing 13. In the exemplary embodiment of the built-in oven 11 according to the invention, the door lock 44 is provided with an integrated automatic opening device 41, which causes the door 40 to open a gap automatically, i.e. without being initiated by an operator.A gap is understood to mean an opening of a few angular degrees compared to the fully closed state (hereinafter referred to as closed), such that the shortest measured distance from the upper door edge 403 to the housing 13 is between one and five centimeters. This state of the door 40 is referred to below as being slightly open. Any opening of the door 40 beyond this is referred to as being open. Of course, the automatic opening device 41 can also be integrated at a different location on the housing 13 and / or the door 40, i.e. not in the door lock 44. Advantageously, in addition to the automatic opening device 41, an automatic closing device 42 is also provided, with which the slightly open door can be closed again such that the gap is at least approximately zero centimeters.In its simplest form, such a locking device 42 is implemented by a spring arrangement, for example, in the area of ​​the door hinges (not shown). The automatic opening device 41 can, particularly if it is not integrated into the door lock, be designed as a motor-driven or otherwise electrically actuated slider (also not shown). In the embodiment shown in FIGS. <h2 style=";text-align:left;direction:ltr"> Figure 2a to cBox 43 indicates the variant in which the door lock 44 and the automatic opening and closing devices 41 and 42 are integrated into a single assembly. A possible structure and function of such a door lock are disclosed, for example, in European patent applications EP 3 324 124 A1 and EP 3 324 125 A1 and are therefore not described in detail here. A door opening sensor 45 is also integrated into such a door lock 44. The door opening sensor 45 detects at least the three states "door closed," "door slightly open," and "door open" and is capable of transmitting distinguishable signals or measured values ​​to a control device 60, by means of which the control device 60 can detect and respond to the various opening states through appropriate programming.

[0024] In the <h2 style=";text-align:left;direction:ltr"> Figure 2a to cIt can also be seen that a first opening 311 is arranged in the ceiling 31. Above the first opening 311, an adjustable first flap unit 312 is arranged, with which the opening cross-section can be changed. For reasons of simplicity of illustration, the first flap unit 312 is shown pivotable here. Preferably, the flap unit 312 and its adjusting device (actuator in the form of an electric motor, not shown) will have a structure as known from DE 10 2016 121 834 A1 and in the <h2 style=";text-align:left;direction:ltr"> Figure 3a to c is shown schematically. This means that a flap 313 with an integrated smaller flap opening 314 will be arranged above the larger first opening 311 and can be displaced in a plane parallel to the plane of the opening 311. There is then a first state in which the flap opening 314 lies above the first opening 311 (small opening, <h2 style=";text-align:left;direction:ltr"> Figure 3a) and consequently only the opening cross-section of the flap opening 314 is released, a second state in which the flap 313 is pushed to the side and completely releases the first opening 311 in the ceiling 31 (enlarged opening, <h2 style=";text-align:left;direction:ltr"> Figure 3b ), and a third state in which the flap opening is located next to the first opening 311 and the flap completely closes the opening 311 (closed opening 311, <h2 style=";text-align:left;direction:ltr"> Figure 3c ).

[0025] Above the cooking chamber 30, a space 80 for electrical and electronic components is separated by a metal sheet 81, which is also surrounded by the housing 13. This space 80 is delimited at the front by the control panel 70, and at the top, sides, and rear by the walls of the housing 13. In this space, along with other electrical and electronic components not shown here, the control device 60 is arranged, which is preferably designed as a microprocessor controller. This control device 60 receives measured values ​​and input data, among other things from the proximity sensor 73 and the control device 72, but also from the door opening sensor 45. It controls, among other things, the first flap unit 312 and the automatic opening and closing devices 41 and 42 via control commands. The individual heating devices 37 are also switched on and off by the control device 60, either directly or via an interposed power unit (not shown).The dashed arrows 61 to the control device 60 symbolize the data lines via which measured values ​​and signals are transmitted, the dashed arrows 62 to components symbolize lines via which control commands are issued by the control device 60. In the following, the measured values ​​and signals themselves are designated by the reference numeral 61 and the control commands by the reference numeral 62. A cooling fan 85 is also arranged in the space 80 to cool the electrical and electronic components. This cooling fan can be switched on and off and its speed can be controlled or regulated by the control device 60. In a special embodiment, the cooling fan 85 can be rotated in both directions, and the direction of rotation can be set by the control device 60.By rotating in a first direction, the cooling fan 85 draws in cold air from the surroundings of the cooking appliance 10 through upper openings 132 in the housing 13 and transports this air as an exhaust air stream into the space 80 for electrical and electronic components. The cold air is symbolized by white arrows 21. A large portion of the exhaust air stream is then directed through openings 810 in the sheet metal 81 into a flow line 82 formed by a gap between the sheet metal 81 and the ceiling 31 of the cooking chamber 30. There, the air stream sweeps over the outer side 310 of the cooking chamber ceiling 31 and there over the first opening 311 or the first flap unit 312. In doing so, the air stream entrains and mixes with hot steam (symbolized by the black arrows 20) rising from the small or enlarged first opening 311 from the cooking chamber.The resulting warm air (symbolized by the gray arrows 22) then exits the slot-shaped opening 83, which consequently functions as an exhaust opening. There is also an embodiment of a cooking appliance 10 (not shown in the drawings) in which the cooling fan 85 and associated air paths are designed such that the steam 20 is drawn from the first opening 311 into the cooling fan 85, where it is mixed with cold air 21 that is also drawn in from the appliance's surroundings.

[0026] With the cooking appliance in this embodiment (or the described modifications), individual variants of a method according to the invention for cooling the escaping steam 20 from the cooking chamber 30 by means of a cooling device 65 (see <h2 style=";text-align:left;direction:ltr"> Figure 4) if a corresponding control command 62 is triggered by the control device 60. The method is initially general, ie also for the further embodiments, using a block diagram in the <h2 style=";text-align:left;direction:ltr"> Figure 4shown. For this purpose, the controller 60 must receive a signal or a measured value 61 from the proximity sensor 73, from which it recognizes that a person 63 has approached the sensor 73 and thus the cooking appliance 10 to within a predetermined distance 64 (in the range of 1 to 2 meters). The proximity sensor 73 itself can be constructed in such a way that it only generates a signal 61 when this predetermined distance 64 is undershot. However, it can also continuously deliver measured values ​​61 to the control device 60, the value of which correlates with the distance 64 from persons 63 in the area of ​​the appliance 10, and the control device 60 then triggers the control command 62 to actuate the cooling device 65 when the value of the measured value 61 exceeds a predetermined threshold.In any case, it is advantageous if the cooling function is not permanently implemented during each operation of the cooking appliance 10, i.e., in each cooking program (there are programs in which the proportion of hot steam in the cooking chamber 30 is so low that it does not cause interference when the door 40 is opened; there are also situations in which people 63 frequently approach the cooking appliance 10 during the execution of a cooking program and it is therefore not desired that the cooling device 65 is activated each time; moreover, there are programs such as a pyrolysis cleaning program in which the door 40 cannot be opened at all), but rather if an operator 63 must enable the cooling function, particularly when setting the program via the operating device 72. This enable can be achieved by switching on the proximity sensor 73 only in cooking programs in which the enable has been given.Alternatively, the signals or measured values ​​61 of the proximity sensor 73 can be evaluated by the control device 60 only in those programs for which the release has been given. Release can also be blocked by the control device 60, for example, when a pyrolysis cleaning program is being carried out. The following description assumes, whenever the term program or cooking program is used, that release has been given for this program. However, it is emphasized again that such a release option is only an advantageous embodiment of the invention and does not have to be mandatory. It is also advantageous if the control device 60 recognizes that a person 63 to whom the proximity sensor 73 has responded does not actually represent an operator 63 in the sense that they also open the door 40.For this purpose, the previously described door opening sensor 45 is provided, which detects the three states "door closed," "door slightly open," and "door open" and is capable of transmitting distinguishable signals or measured values ​​61 to the control device 60, by means of which the control device 60 can detect and react to the various opening states. After detecting the approach of a person 63 via the signal or measured value 61 of the proximity sensor 73, the control device 60 counts down a predetermined period of time. If the signal or measured value 61, which correlates with the open state of the door 40, is absent within this period, the control device 60 deactivates the cooling device 65 and the cooking program continues.

[0027] Here is the description of the different variants, which are related to the design according to the <h2 style=";text-align:left;direction:ltr"> Figure 1 and <h2 style=";text-align:left;direction:ltr"> 2a to c can be executed. 1.1 Increasing the cooling fan's airflow 85

[0028] To this end, when a person 63 approaches, the control device 60 first switches on and starts the cooling fan 85, if this was not already the case in the current program. When the cooling fan 85 is then running, or if it was already running previously in the program, its speed is increased by the control device 60 compared to the speed of conventional programs. This is easiest to achieve when there are several different speed levels (for example, a high, a medium, and a low) and when the cooling fan 85 is operated at a low or medium speed level or even not at all in a cooking program, and when it is switched to the high speed level for the cooling function.Of course, cooling fan 85 and control device 60 can also be designed to implement continuous speed changes and then, for example, to implement a percentage speed increase or an increase in speed by a predetermined speed difference for the cooling function. As already explained in the introduction to the description, the increase in speed increases the exhaust air flow and thereby increases the mixing of the hot steam 20 exiting the first opening 311 with cold air 21. Thus, more hot steam 20 is taken from the cooking chamber, mixed with cold air 21, and blown out of the opening 83 as warm air 22, which in this case functions as an exhaust opening; see . <h2 style=";text-align:left;direction:ltr"> Figure 2a. When the operator 63 then opens the door 40, the steam 20 in the cooking chamber 30 has already been partially replaced by cold air 21 and has therefore been cooled down, so that the temperature and thus also the quantity of steam 20 escaping from the open loading opening is reduced. 1.2 Enlarging the first opening 311

[0029] For this purpose, when a person 63 approaches, the first flap unit 312 is set by the control device 60 into the second state, in which the flap 313 is pushed to the side and completely exposes the first opening 311 in the ceiling 31. Hot steam 20 will then increasingly emerge from the first opening 311 and escape from the cooking chamber 30 via the flow line 82 and the exhaust opening 83, see also <h2 style=";text-align:left;direction:ltr"> Figure 2a. This results in cold air 21 being drawn in through leaks in the cooking chamber 30, and the atmosphere in the cooking chamber 30 having already cooled down when the door 40 is opened by the operator 63. Advantageously, the enlargement of the first opening 311 is combined with an increase in the exhaust air flow of the cooling fan 85 (1.1). This, on the one hand, extracts even more steam 20 from the cooking chamber, and on the other hand, the steam 20 flowing out of the exhaust opening 83 is first mixed with cold air 21 and cooled. 1.3 Opening the door in a gap 40

[0030] In a further variant, when a person 63 approaches, the door 40 is moved into a slightly open state. Hot steam 20 then flows out of the opened gap, see <h2 style=";text-align:left;direction:ltr"> Figure 2b, and is replaced by incoming cold air 21. This cools the atmosphere in the cooking chamber when the door 40 is fully opened by an operator 63. This variant can also be advantageously combined with one or both of the measures described under 1.1 and 1.2. As a result, the steam 20 escaping from the door gap is mixed with the cold or warm air 21 or 22, respectively, flowing through the flow line 82 from the exhaust opening 83. 1.4 Reversing the direction of rotation of the cooling fan 85

[0031] A reversal of the direction of rotation of the cooling fan 85 (meaning the rotor not shown here and thus the fan blades of the cooling fan 85, also not shown) when a person 63 approaches in a second direction of rotation by the control device 60 converts the exhaust air flow into an intake air flow. The resulting air flow is in <h2 style=";text-align:left;direction:ltr"> Figur 2cshown in a cooking appliance 10 with a partially open door 40. Cold air 21 from the environment in front of the cooking appliance 10 is conveyed through the opening 83, which now functions as an intake opening, into the flow line 82. In this way, the cold air 21 mixes with the hot steam 20, which exits from the door 40 opened by the operator 63 and is also sucked in, even before the cooking appliance 10. The warm air resulting from the mixture is conveyed through the flow line 82 and the openings 810 in the sheet 81 to the cooling air fan 85 and from there blown outside. By sucking in the hot steam 20 and mixing it with the cold air 21, the steam 20 is not only cooled but also deflected away from the operator 63, so that the door 40 can be opened safely. This variant can also be combined with one or more other measures, in particular with the one described under 1.2 described enlargement of the first opening 311 - then a part of the hot steam 20 is also sucked out of the cooking chamber 30 through this and is already cooled there - and / or particularly advantageously with the gap-wise opening of the door 40 described under 1.3 - as a result, a part of the steam 20 is sucked out of the cooking chamber via the gap-open door and replaced by colder air 21 even before the operator 63 arrives at the device 10. 2. Second embodiment

[0032] The <h2 style=";text-align:left;direction:ltr"> Figures 5a and bshow a further embodiment of a cooking appliance 10, which is modified in the area of ​​the exhaust / suction opening 83. For this purpose, a strip 84 is pivotally mounted at the front end of the flow line 82, preferably on the sheet metal 81, the underside of which defines the upper limit of the flow line 82. The pivot axis 841 of the strip 84 extends parallel to the longitudinal extent of the exhaust / suction opening 83 at least approximately across the entire width of the cooking appliance 10. Recesses in the area of ​​the door lock 44 can be provided if necessary (not shown in the figure). The mounting of the strip 84 is designed such that it can be moved into the position shown in FIG. 1 solely by gravity. <h2 style=";text-align:left;direction:ltr"> Figure 5bshown position (deflection position 843). At least one driver 46 is arranged on the upper edge 403 of the door 40, which is dimensioned in terms of its longitudinal extent 461 such that it engages so far into the pivoting range of the bar 84 that it presses the bar 84 into an at least approximately horizontal position (inactive position 842) when the door 40 is closed, see <h2 style=";text-align:left;direction:ltr"> Figure 5a . Preferably, the driver 46 should only cover a few millimeters in its transverse extent (not shown, points in the plane of the drawing) so that it only blocks the exhaust / suction opening 83 to a small extent when the door 40 is closed. 2.1 How it works

[0033] The <h2 style=";text-align:left;direction:ltr"> Figures 5a and 5b clearly show the functionality of the design by illustrating the flow conditions. <h2 style=";text-align:left;direction:ltr"> Figure 5aWhen the door 40 is closed, the bar 84 is pivoted backwards into its horizontal, inactive position 842 by the driver 46. In this position, the cooling fan 85 (see <h2 style=";text-align:left;direction:ltr"> Figure 2a to c ) generated blow-out air flow can escape essentially unhindered past the one or more drivers 46 through the flow line 82 from the blow-out opening 83. In the <h2 style=";text-align:left;direction:ltr"> Figure 5b When the door 40 is opened as shown, the strip falls into its vertical deflection position 843 and deflects the exhaust air flow downwards after exiting the exhaust opening 83. This creates an air curtain that prevents the hot steam 20 from escaping (see <h2 style=";text-align:left;direction:ltr"> Figure 2a to c) from the cooking chamber 30. This function is known per se from the prior art and therefore not according to the invention, nor does it constitute a cooling device according to the invention, since the steam 20 is only prevented from escaping from the cooking chamber 30, but not cooled. However, it can be used very advantageously with the measure described under 1.1 of increasing the blow-out air flow of the cooling fan 85 and even more advantageously with the enlargement of the first opening 311 described under 1.2 (see <h2 style=";text-align:left;direction:ltr"> Figure 2a to c ). A combination of this measure with the gap-wise opening of the door 40 as the operator 63 approaches, as described in 1.3, is particularly advantageous. Then, the strip 84 is already in the deflection position 843 before the door 40 is fully opened, and the protective air curtain is already in place. Of course, a combination with the measures described in 1.1 and / or 1.2 is also possible. 3. Third embodiment

[0034] The <h2 style=";text-align:left;direction:ltr"> Figure 6a to c show a further embodiment of a cooking appliance 10 according to the invention with a cooling device 65. The cooling device 65 here is a second opening 330 which, as in the <h2 style=";text-align:left;direction:ltr"> Figure 6a recognizable preferably arranged in the rear wall 33 of the device 10, in combination with a second flap unit 331, which is in the <h2 style=";text-align:left;direction:ltr"> Figures 6b and 6c shown in two different views. The flap unit 331 has a closure plate 332, which can be moved by a pivoting arm 333 by means of an actuator in the form of an electromagnet 334 into two different positions, namely a closed position (in the <h2 style=";text-align:left;direction:ltr"> Figures 6b and 6c shown) and an open position (in the <h2 style=";text-align:left;direction:ltr"> Figure 6a(shown schematically). The electromagnet 334 is switched by the control device 60 and, as already described above in connection with the other cooling devices 65, is always actuated when the control device 60 detects the approach of a person 63 via the proximity sensor 73. The use of an electromagnet 334 enables very rapid actuation of the pivot arm 333 and the closure plate 332 within a period of less than one second. 3.1 How it works

[0035] When a person 63 approaches, the proximity sensor 73 sends a signal 61 to the control device 60. This then sends a control command 62 to the electromagnet 334 and the electromagnet moves the locking plate 332 via the pivot arm 333 into the <h2 style=";text-align:left;direction:ltr"> Figure 6ashown open position. Cold air 21 then flows through the second opening 330 into the cooking chamber 30 and mixes with the hot steam 20, cooling it down. Preferably, the control device 60 also switches on the circulating air fan 373, if this was not already in operation during the current program, in order to intensify the mixing of the cold air 21 and the hot steam 20. Particularly preferably, the flap 313 of the first flap unit 312 is also pushed to the side (see 1.2) and the first opening 311 in the ceiling 31 is completely opened, so that the mixture of cold air 21 and hot steam 20 (warm air 22) can flow out of the cooking chamber 30 even better via the flow line 82 and the exhaust opening 83, and more cold air 21 is sucked in through the second opening 330. In particular, the exhaust air flow of the cooling fan 85 can then be increased (see 1.1) and the previously described effect can be further enhanced.Opening the door 40 in a gap (see 1.3) may also be advantageous.

[0036] Of course, it is also advantageous in this embodiment if, as described under 1., the cooling device 65 is deactivated again when the control device 60 recognizes that the approaching person 63 is not an operator 63 at all. 4. Fourth embodiments

[0037] In the <h2 style=";text-align:left;direction:ltr"> Figure 7a and 7b show two different embodiments of cooking appliances 10, in which a further fan 121 is provided as a cooling device 65, which fan at least partially sucks the hot steam 20 out of the cooking chamber 30 and replaces it with cold air 21. <h2 style=";text-align:left;direction:ltr"> Figure 7ashows the first embodiment of the cooking appliance 10 using the example of a built-in oven 11. The fan 121 is integrated into the rear, lower part of the appliance 11 in the space between the cooking chamber rear wall 33 and the housing rear wall 131. The suction area 122 is directed into a flow line 821, which in this appliance extends not only from the blow-out / suction opening 83 into the space between the sheet metal 81 and the ceiling 31 of the cooking chamber 30, but also on the rear of the appliance into the space between the cooking chamber rear wall 33 and the housing rear wall 131. The blow-out area 123 of the fan 121 is directed towards a lower opening 133 in the housing rear wall 131. In an alternative not shown in the drawings, the further fan 121 can also be arranged outside the built-in oven 11, for example in a base of a kitchen unit (not shown).Then, the flow line 821 must be extended by an intake hose or an intake pipe (not shown) between the lower opening 133 in the housing rear wall 131 and the intake area 122 of the blower 121. The blower 121 is switched on / off by the control device 60 and, if necessary, its speed is also controlled.

[0038] In the embodiment according to the <h2 style=";text-align:left;direction:ltr"> Figure 7bIn addition to a built-in oven 11 or other cooking appliance 10 with a cooking chamber 30, such as a steamer or microwave oven, a cooking hob 12 is also provided, which is equipped with a device 120 for extracting cooking vapors. The additional fan 121 is then also a component of this device 120 and can extract cooking vapors that arise in the area of ​​the cooking hob 12 when boiling water and cooking food via a further flow line 124, which is led from an opening (not shown) in the area of ​​the cooking hob 12 to the intake area 122 of the fan 121. The fan 121 shown in the previous embodiment ( <h2 style=";text-align:left;direction:ltr"> Figure 7a ) described flow line 821 from the exhaust / suction opening 83 to the suction area 122 of the further fan 121 is present. The system 13 comprising hob 12 and cooking appliance 10 with cooking chamber 30 can, as in the <h2 style=";text-align:left;direction:ltr"> Figure 7bshown, be designed as a combined unit, for example as a stove or as a built-in oven, built-in steam cooker or built-in microwave oven with a cooking surface arranged directly above it. Then it can be advantageous if the two flow lines 124 and 821 have a common part 125, which is arranged in particular in the cooking appliance 10 with cooking chamber 30. At the interface of the two separate parts of the flow lines 124 and 821, a switching device 126 actuated by the control device 60 can preferably be arranged, via which switching device 126 one or the other separate part of the flow lines 124 or 821 can be selectively blocked. In this way, it is ensured that the additional fan 121 is only active for the respectively released area. As an alternative to the <h2 style=";text-align:left;direction:ltr"> Figure 7bIn the embodiment shown, the hob 12 can also be arranged separately from the cooking appliance 10 with the cooking chamber 30, i.e., not directly above it. Then, the flow lines 124, 821, and 125 will be at least partially connected to the additional fan 121 via hose / pipe connections. The fan 121 itself can then be installed, for example, in a kitchen base. The switching device 126 will then either be assigned to the additional fan 121 (either integrated or pre-installed), or a part of the switching device 126 will be arranged in both the hob 12 and the cooking appliance 10, which can open or close the respective flow line 124 or 821.

[0039] There can either be a control device 60 that operates jointly for the cooking appliance 10 and the hob 12. Alternatively, both appliance parts 10 and 12 can have their own control devices 60. In this case, however, it must be ensured that these control devices 60 can exchange data to implement the cooling function of a cooling device 65 according to the invention, or that the control device 60 of the cooking appliance 10 can control the components necessary for implementing such a cooling function. In an arrangement in which the additional fan 121 is installed separately from at least one of the appliances, hob 12 and cooking appliance 10, there will be data lines or wireless data transmission between the control device(s) 60 and the fan 121. 4.1 Functionality

[0040] When a person 63 approaches, the proximity sensor 73 sends a signal 61 (not shown) to the control device 60, which is responsible for implementing the cooling function of the cooling device 65 according to the invention. This then sends a control command 62 (not shown) to the additional fan 121 and switches it on (possibly at a preset speed). If it was not already switched on during use of the hob 12 to extract cooking fumes, in which case only the speed needs to be adjusted if necessary. A further control command 62 (not shown) is sent to the switching device 126. This is controlled in such a way that it releases the flow line 821 (and if applicable 125) between the exhaust / suction opening 83 and the suction area 122 of the further fan 121 and blocks the further flow line 124 between the opening in the area of ​​the cooking surface 12 and the suction area 122 of the further fan 121.As a result, the hot steam 20 which flows out when the operator 63 opens the door 40 is sucked away by the operator into the opening 83 which functions as a suction opening. As shown in the . <h2 style=";text-align:left;direction:ltr"> Figure 7aand b, the first opening 311 is present in the cooking chamber ceiling 31, a portion of the hot steam 20 is already being diverted from the cooking chamber 30 through the opening 311 and replaced by cold air 21. If the opening 311 can be closed by a controllable first flap unit 312, it is advantageous for the control device 60 to set the flap unit 312 into the second state, in which the flap is pushed to the side and completely exposes the first opening 311 in the ceiling 31, see 1.2. A combination with the gap-by-gap opening of the door 40 described in 1.3 is particularly advantageous - as a result, a portion of the steam 20 is sucked out of the cooking chamber 30 via the gap-open door 40 and replaced by colder air 21 even before the operator 63 arrives at the appliance 10.

[0041] Of course, it is also advantageous in this embodiment if, as described under 1., the cooling device 65 is deactivated again when the control device 60 detects that the approaching person 63 is not actually an operator 63. In this case, the switching device 126 should also be controlled such that it blocks the flow line 821 between the exhaust / intake opening 83 and the intake area 122 of the additional fan 121 and opens the additional flow line 124 between the opening in the area of ​​the hob 12 and the intake area 122 of the additional fan 121. Such a switchover should also be performed when the cooling process is complete, which is determined, for example, by the control device 60 after a predetermined time has elapsed after the door 40 has been completely opened (detected by the door opening sensor 45). 10 Cooking appliance 11 Built-in oven 12 Hob 13 System comprising hob and cooking appliance 14 External environment 120 Device for extracting cooking fumes 121 Additional fan 122 Intake area 123 Exhaust area 124 Additional flow line 125 Common part of flow lines 124 and 821 126 Switching device 13 Casing 131 Rear wall of casing 132 Upper openings 133 Lower opening 20 Vapors or steam 21 Cold air 22 Warm air 30 Cooking chamber 31 Ceiling 310 Exterior 311 First opening 312 First flap unit 313 Flap 314 Flap opening 32 Floor 33 Rear wall 330 Second opening 331 Second flap unit 332 Closing plate 333Swivel arm 334Electromagnet 34Side wall 35Side wall 36Loading opening 37Heating device 371Top heat element 372Ring heater 373Circulation fan 374Shielding plate 375Openings 376Bottom heat element 40Door 401Lower edge 402Upper area 403Upper door edge 41Automatic opening device 42Automatic closing device 43Box 44Door lock 45Door opening sensor 46Driver 461Longitudinal extension60Control device 61Arrow for signal or measured value 62Arrows for control command 63Person, operator 64Distance 65Cooling device 70Control panel 71Display device 710Display 72Operating device 720Push button 73Proximity sensor 80Space for electrical / electronic components 81Sheet metal 810Openings 82Flow line 821Flow line ( <h2 style=";text-align:left;direction:ltr"> Figure 6a, b ) 83 Exhaust / intake opening 84 Bar 841 Swivel axis 842 Inactive position 843 Deflection position 85 Cooling fan

Claims

1. Method for cooling the escaping vapour or steam (20) from the cooking chamber (30) of a cooking appliance (10), in particular of an oven or steamer, the cooking appliance (11) being equipped with: a cooking chamber (30), a door (40) for closing a front loading opening (36) of the cooking chamber (30), a cooling device (65) for replacing part of the vapour or steam (20) in the cooking chamber (30) with cold air (21) and a control device (60) for actuating the cooling device (65) via a control command (62), the control command (62) being triggered by the signal or the measured value (61) of a proximity sensor (73) arranged on the cooking appliance (10) before a person (63) as an operator manually opens the door (40), the signal or the measured value (61) being generated by the proximity sensor (73) as a result of a person (63) approaching the cooking appliance (10), characterised in that the cooling device (65) carries out at least one of the following method steps as a result of the control command (62) of the control device (60): • increasing an exhaust air flow of a cooling fan (85), the air flow picking up part of the vapour or steam (20) from the cooking chamber (30) via a first opening (311) in the ceiling (31) of the cooking chamber (30) and transporting it out of the cooking appliance (10) via a flow line (82); • increasing the first opening (311) in the ceiling (31) by moving an adjustable first flap unit (312); • uncovering a second opening (330) in one of the cooking chamber walls (31, 32, 33, 34, 35) by moving an adjustable second flap unit (331).

2. Method according to the preceding claim, characterised in that the cooling device (65) additionally carries out at least one of the following method steps as a result of the control command (62) of the control device (60): • generating a suction air flow via the cooling fan (85) or via an additional fan (121), the suction air flow being sucked in via a flow line (82, 821) by the cooling fan (85) or the additional fan (121) and the flow line (82) extending at least from the cooling fan (85) or the additional fan (121) to an exhaust / suction opening (83) above the cooking chamber (10); • opening the door (40) by a gap via an automatic opening device (41);3. Method according to the preceding claim, characterised in that the air flow of the cooling fan (85) is increased by raising the fan speed via the control device (60).

4. Method according to at least one of the two preceding claims, characterised in that the suction air flow is generated by reversing the direction of rotation of the cooling fan (85) via the control device (60).

5. Method according to at least one of the three preceding claims, characterised in that the first or second flap unit (312, 331) is moved by servodrives (334) actuated by the control device (60).

6. Method according to at least one of the four preceding claims, characterised in that the control unit (60) and the second flap device (331) are configured to uncover the second opening (330) within a time period of less than 5 seconds, in particular less than 3 seconds, in particular a maximum of only 1 second.

7. Method according to at least one of the five preceding claims, characterised in that when the second opening (330) is uncovered via the control device (60), the control device switches on a circulating fan (373) for circulating the air or the vapour or the steam (20) in the cooking chamber (30).

8. Method according to at least one of the preceding claims, characterised in that the cooling device (65) is only actuated in response to a control command (62) of the control device (60) in a cooking program if, when switching on the cooking program or during the course of the cooking program, an operator (63) has previously given approval via an operating device (72) of the cooking appliance.

9. Method according to the preceding claim, characterised in that the proximity sensor (73) is switched on by the approval of the operator (63).

10. Method according to at least one of the preceding claims, characterised in that the control device (60) deactivates the cooling device (65) if a door opening sensor (45) does not sense that the door (40) is open by more than a gap within a predetermined time period after the control command (62) has been triggered by the signal or the measured value (61) of the proximity sensor (73).

11. Method according to the preceding claim, characterised in that the control device (60) closes the door completely again by means of an automatic closing device (42) if the door opening sensor (45) does not sense that the door (40) is open by more than a gap within a predetermined time period after the control command (62) has been triggered by the signal or the measured value (61) of the proximity sensor (73).

12. Cooking appliance (10), in particular an oven or steamer, comprising a cooking chamber (30), a door (40) for closing a front loading opening (36) of the cooking chamber (30), a cooling device (65) for replacing part of the vapour or steam (20) in the cooking chamber (30) with cold air (21), a control device (60) for actuating the cooling device (65) in response to a control command (62), and a proximity sensor (73) for generating a signal or a measured value (61) as a result of a person (63) approaching the cooking appliance (10), and a flow line (82) for guiding the exhaust air flow or suction air flow, which flow line extends at least from a cooling fan (85) or an additional fan (121) to an exhaust and / or suction opening (83) above the cooking chamber (30), characterised in that a first opening (311) is provided in a ceiling (31) of the cooking chamber (30), which first opening fluidically connects the cooking chamber (30) to the flow line (82, 821) and can be at least partially closed by a first flap unit (312), and / or by a second opening (330) in a rear wall (33) of the cooking chamber (30), which second opening fluidically connects the cooking chamber (30) to the outside environment (14) of the cooking appliance (10) and can be at least partially closed by a second flap unit (331), the control device (60) being suitable and configured for carrying out the control command (62) for carrying out the method according to at least one of the preceding claims.

13. Cooking appliance (10) according to the preceding claim, comprising a cooking hob (12) arranged in the upper region of the cooking appliance and an apparatus (120) for extracting cooking fumes arising in the region of the cooking hob (12),characterised in that the additional fan (121) is part of the apparatus (120) for extracting cooking fumes.

14. Cooking appliance according to the preceding claim, characterised by an additional flow line (124, 125) between the cooking hob (12) and the additional fan (121), and characterised by a switching apparatus (126) actuated by the control device (60), which switching apparatus is suitable and designed for establishing a fluidic connection between the additional fan (121) and optionally the additional flow line (124) or a flow line (821) between the exhaust / suction opening (83) and the additional fan (121).

15. Cooking appliance (10) according to at least one of the three preceding claims, characterised in that in the region of the exhaust / suction opening (83), a pivotable bar (84) is arranged which, in a first position (842), releases the exhaust air flow from the exhaust / suction opening (83) at least approximately in the direction of the flow line (82, 821), and, in a second position (843), diverts the exhaust air flow in a direction parallel to the loading opening (36).

16. Cooking appliance (10) according to the preceding claim, characterised in that at least one part of the bar (84) projects into the pivoting range of at least one part (46) of the door (40), so that the bar (84) is in the first position (842) when the door (40) is closed and in the second position (843) when the door (40) is open.