EP3285011A2 - Cooking device and method for operating same - Google Patents

Abstract

Cooking appliance (1) comprising a cooking chamber (2), a steam generator (3) and a water supply (4) in connection to the steam generator (3), wherein the cooking chamber by means of the steam generator (3) with steam (5) is heated and wherein the Cooking chamber (2) comprises a steam outlet (6) with a steam discharge (7). The vapor outlet (6) is further followed by a condenser device (8), wherein the condenser device (8) is in operative connection to the water supply (4) and the steam discharge (7). In a method for operating such a cooking appliance, the water intended for steam production is fed via the condenser device (8) to the steam generator (3). In a further method for operating such a cooking appliance, the steam (5) which escapes from the cooking chamber (2) through the steam outlet (6) is led via the condenser device (8).

Description

The present invention relates to a cooking appliance comprising at least one cooking chamber, at least one steam generator and at least one water supply in connection to the steam generator. The cooking chamber can be heated by means of the steam generator with steam. Furthermore, a steam outlet is provided in the cooking chamber, via which steam emerging from the cooking chamber can be discharged via at least one steam discharge. The present invention further relates to two methods of operating such a cooking appliance.

In cooking appliances, the use of steam for cooking food is known. The use of steam in this case offers a user the opportunity to prepare food very gently. In order to provide steam in the cooking chamber, several methods for steam generation have become known.

In the internal generation of steam water is introduced into the cooking chamber and on a evaporation surface, usually on the cooking chamber floor, heated and evaporated. External steam generators produce steam outside the cooking chamber and do not introduce water but steam into the cooking chamber.

From the state of the art digging machines with a steam generator are known. For example, show the document DE 10 2007 005 503 A1 and the publication DE 10 2006 043 181 A1 such steam cooking appliances.

The publication DE 10 2008 052 117 A1 shows a cooking appliance, in which the steam intended for steam generation is preheated with the steam escaping from the cooking chamber.

A disadvantage of using steam for cooking food, however, is that the evaporation of water requires relatively much energy. Furthermore steam is removed from the cooking chamber via a steam outlet in steam cookers or cooking appliances with steam operation. Depending on the configuration of the cooking appliance, a larger amount of steam is also removed from the cooking chamber into the kitchen, especially at the end of a cooking process. As a result, the kitchen is relatively much moisture. In addition, deposits of minerals can be observed due to operational reasons in aggregates for heating water.

It is therefore the object of the present invention to provide a cooking appliance with steam operation, with which an improvement over the previously described disadvantages is achieved.

This object is achieved by two methods with the features of claims 1 and 2 for operating a cooking appliance and by a cooking appliance for carrying out these methods with the features of claim 1. Preferred developments of the invention are subject of the dependent claims. Further advantages and features of the invention will become apparent from the embodiments.

The cooking appliance according to the invention comprises at least one cooking chamber, at least one steam generator and at least one water supply in operative connection to the steam generator. The cooking chamber can be heated by means of the steam generator with steam, wherein the cooking chamber further comprises at least one steam outlet to which at least one steam discharge is connected. The vapor outlet is further followed by at least one capacitor device, wherein the capacitor device is at least partially in operative connection to the water supply and the steam discharge.

The steam generator of the cooking appliance can be designed both as an external steam generator and as an internal steam generator. If the steam generator is provided as an internal steam generator, the cooking chamber preferably comprises at least one connection possibility for the water supply, so that water to be evaporated can be introduced into the cooking chamber. If the steam generator is provided as an external steam generator, the water supply is preferably connected directly to the steam generator. The steam generator then further suitably comprises at least one outlet for steam, which is preferably connected to at least one steam inlet of the cooking chamber. Also, the use of an external steam generator and an internal steam generator in a device may be advantageous depending on the configuration.

The water supply according to the invention comprises the conduit system for fresh water, which is connected either directly to the steam generator or to the cooking chamber. Furthermore, depending on the configuration, a reservoir and / or a pump may be included in the water supply.

In particular, the steam removal comprises the line system, which is connected to the steam outlet of the cooking chamber and discharges the steam leaving the cooking chamber. Depending on the configuration, the vapor removal can comprise further components such as, for example, a fan and / or a blower.

The capacitor device according to the invention is designed in particular as a condenser and thus preferably provides a heat transfer device. The condenser device is at least partially operatively connected to at least one section of the water supply and / or the steam discharge. It is particularly preferred that the water supply and the vapor removal are arranged to each other or are in operative connection with corresponding components such that a heat transfer from the steam discharge to the water supply is possible.

The cooking appliance according to the invention offers many advantages. A significant advantage is that a cooking device with steam operation with a better energy balance is provided by the condenser device downstream of the steam outlet in operative connection to the water supply. The heat of the hot steam emerging from the cooking chamber is at least partially transferred by means of the condenser device to the water to be supplied to the steam generator. As a result, the fresh water for the production of steam is already supplied preheated the steam generator, so that for heating or vaporizing a lower energy input is necessary.

A further advantage is that the hot steam emerging from the cooking chamber condenses in the condenser device or in the condenser, so that already cooled air with a lower humidity and condensate is formed. Significantly reduced for the steam load in the kitchen, as the humidity escaping into the kitchen is minimized by the condenser device.

The capacitor device preferably comprises at least one memory device. The water supply and the vapor discharge are then preferably passed through the storage device or connected to this. Such a storage device may preferably provide at least one cold storage and / or at least one heat storage. For this purpose, in particular a storage device with a good heat capacity can be used. Memory devices made of metal are particularly suitable for this purpose. However, it is also possible to use a storage device which comprises a liquid and / or a salt solution as storage medium.

Particularly preferably, the storage device is provided at least in sections by at least one metal block. In this case, the metal block is in particular designed such that it has a predetermined heat capacity. For example, a metal block of aluminum with a weight of 0.4 to 2.2 kilograms, advantageously be used with a weight of 0.8 to 1.2 kilograms.

In expedient embodiments, the condenser device is arranged directly on the steam outlet. It is to be understood in particular directly as close as possible to the steam outlet. In particular, the condenser device is arranged so close to the steam outlet that a particularly good efficiency of the condenser device is achieved or a particularly good or optimum heat transfer to the intended for evaporation of fresh water takes place. In particular, if a sensor is provided for controlling the cooking process in or on the steam outlet, the condenser device is preferably provided fluidically behind the sensor.

Preferably, the condenser device is assigned at least one condensate discharge. Such a condensate removal can be provided as a separate component or as a separate module, for example, leads via an independent line system resulting in the condensing device condensate in a sanitation. Depending on the configuration, the condensate removal can also be provided by the condenser device itself or by the vapor removal. Depending on the arrangement of the condenser device in the steam discharge, the resulting condensate can easily flow back into the cooking chamber and is either re-evaporated there or, for example, fed to a sanitation.

Preferably, at least one external steam generator is provided, wherein at least one purge line is connected to the steam generator. The flushing line can be designed as a separate line path to the steam generator. Generally, an external steam generator has at least one outlet for steam which is connected to a steam inlet of the cooking chamber. The purge line may also be suitably integrated into the line system between the outlet of the steam generator and the steam inlet of the cooking chamber. For this purpose, in particular, a multi-way valve is provided in the line system between the outlet and the steam inlet of the cooking chamber, so that depending on the application, the cooking chamber can be supplied with steam and / or the steam generator can be rinsed with water. When rinsing the steam generator, the water used for rinsing can then be fed to a sanitation via the rinsing line and preferably a suitable position of the multi-way valve. In particular, the steam generator can be rinsed with cold water at the end of a cooking process, so that it cools faster and thus allows or promoted a faster cooling of the cooking chamber.

Particularly preferably, at least one bypass channel is arranged in the water supply and / or the steam removal. Such a bypass channel in the water supply and / or the vapor removal is intended to not use the capacitor device when needed. These are bypass channels or bypass lines in the water supply to the vapor removal provided, which can be switched in particular via multi-way valves and in particular three-way valves.

It is preferably provided that the water with which the steam generator is completely filled and / or flushed is at least 60 Kelvin colder than the steam produced by the steam generator. For this purpose, fresh water can be used from a water supply, which usually has a temperature between 0 ° C and 30 ° C. Alternatively or additionally, it is possible to recycle water from the outlet of the steam generator to the water supply.

In a return of the water from the outlet to the water supply, the water is preferably passed through the condenser device and cooled there, so that the water passes into the steam generator has a temperature of less than 40 ° C.

The inventive method is suitable for operating a cooking appliance, as described above. In this case, the water intended for steam production can be supplied to the steam generator at least temporarily via the condenser device.

Furthermore, the steam flowing out of the cooking chamber is preferably at least temporarily discharged via the condenser device.

The method according to the invention offers many advantages. In particular, a method for recovering energy from exhaust air can be provided, in which the energy contained in the steam flowing out of the cooking chamber is transferred by means of the condenser device to the water used for the production of steam. Thus, the water used for evaporation is preheated before being introduced into the steam generator, so that less energy is required to evaporate the water.

Preferably, the water intended for steam production is supplied to the steam generator as a function of the steam content in the cooking chamber via the condenser device. For this purpose, in particular at least one switchable water supply or switchable steam removal is provided, so that the intended water for steam production is then passed through the condenser device as soon as a certain proportion of steam in the cooking chamber is present.

Another method according to the invention is suitable for operating a cooking appliance, as described above. In this case, the steam which escapes from the cooking chamber through the steam outlet is guided at least temporarily over the condenser device.

Preferably, the method according to the invention is used in combination at least temporarily combined with the method described above, so that the water to be evaporated and the steam flowing out of the steam outlet are passed over the condenser device.

This inventive method for operating a cooking appliance offers many advantages. A significant advantage is that this method provides a process for drying the exhaust air of a steamer. In particular, the steam escaping from the cooking chamber is condensed in the condenser device, so that the vapor pressure in the kitchen or the moisture escaping into the kitchen is considerably reduced.

At least at the end of a cooking process, the condenser device is preferably flushed with fresh water at least temporarily. This ensures that in the condenser device, a significant proportion of the steam escaping from the cooking chamber is condensed, so that a particularly effective drying of the exhaust air can take place.

Another method according to the invention is suitable for operating a cooking appliance, as described above. In this case, the steam generator and / or the cooking chamber is at least temporarily filled with water or rinsed and cooled so the steam generator and / or the cooking chamber. As a result, a rapid reduction of the steam content in the cooking chamber can be achieved. In particular, in this way the vapor pressure in the kitchen or the moisture escaping from the cooking appliance, in particular in connection with the opening of the cooking chamber door, can be considerably reduced. Also can be achieved by the flooding of the steam generator at the end of a cooking process that the steam generator cools quickly, which significantly reduces the formation of mineral deposits.

In expedient embodiments, the water used for rinsing is supplied to a sanitation. Alternatively, depending on the configuration of the cooking appliance, the water used for rinsing can also be returned to a water supply. By discharging the water used for rinsing can be achieved in particular that the capacitor device and the steam generator can be flushed with larger amounts of water in order to achieve a particularly effective cooling of the components.

As a result of the rapid cooling of the steam generator or of the components of the cooking appliance connected to it in a heat-conducting manner, rapid cooling of the cooking chamber can be achieved. So it is possible, especially by increased condensation in the cooking chamber, possible to reduce the amount of steam before opening the oven door considerably and / or specifically interrupt a cooking process.

If no connection to a sewer is available, the above-mentioned advantage can also be achieved by rinsing the water for cooling the steam generator in a circuit through the steam generator. For this purpose, it has proved to be advantageous that the cooking appliance has a return line which connects an outlet of the steam generator with an inlet of the steam generator. Preferably, a pump is arranged in the conduit path of this return line, by means of which the water is circulated.

In a circulation operation, the water can be passed to the outlet of the steam generator via the condenser and deliver there heat energy to the memory.

Preferably, simultaneously with the shutdown of a heater of the steam generator or immediately after switching off a heater of the steam generator, in particular within less than 30 seconds, preferably within less than 5 seconds, the steam generator is flushed or filled with water.

Further advantages and features of the present invention will become apparent from the embodiments, which are explained below with reference to the accompanying figures.

According to the invention, a cooking process includes all processes which are directly or indirectly related to the preparation of a food. In particular, the cooking process is not finished before the food was removed from the oven. Cleaning and descaling processes that do not run in the immediate context of a cooking program are therefore to be distinguished from the understanding of the term cooking according to the invention.

Figur 1

eine rein schematische Darstellung eines erfindungsgemäßen Gargerätes; und

Figur 2

eine rein schematische Darstellung eines weiteren Ausführungsbeispiels eines erfindungsgemäßen Gargerätes.

In the figures show:

FIG. 1

a purely schematic representation of a cooking appliance according to the invention; and

FIG. 2

a purely schematic representation of another embodiment of a cooking appliance according to the invention.

In FIG. 1 are purely schematically various components of a cooking appliance 1 according to the invention in a sectional view from the side. The cooking appliance 1 according to the invention is designed as a steam cooker 100 and comprises a cooking chamber 2, which can be supplied with steam 5 by means of a steam generator 3.

For generating steam 5, the steam generator 3 is formed in the embodiment shown as an external steam generator 3, which is supplied via a water supply 4 with fresh water. The fresh water supply comprises in the illustrated embodiment, a line system 18 and a pump 19 and a water supply 13th

The external steam generator 3 further comprises an outlet 21, via which steam 5 generated in the steam generator 3 can be supplied via a line system 22 to a steam inlet 15 of the cooking chamber 2 and thus to the cooking chamber 2.

Furthermore, the cooking chamber 2 in the exemplary embodiment shown comprises a steam outlet 6, via which excess steam 5 or generally steam 5 is removed from the cooking chamber 2. For controlling the cooking process and in particular for controlling the amount of steam in the cooking chamber 2, a sensor device 23 or a temperature sensor 24 is arranged directly in or on the steam outlet 6, so that via the detected temperature in the steam outlet to a saturation of the cooking chamber 2 with steam. 5 can be closed.

To the steam outlet 6, a steam discharge 7 is connected, wherein in the embodiment shown, the exiting from the cooking chamber 2 steam 5 via a line system 20 of the steam discharge 7 supported by a fan 25 is discharged from the cooking device 1.

According to the invention, the cooking appliance 1 comprises a condenser device 8, which is in operative connection to the water supply 4 and the steam discharge 7. Here, the capacitor device 8 is formed in the embodiment shown as a condenser 26 and as a heat transfer device 27.

In the exemplary embodiment shown, the water supply 4 and the steam discharge 7 are introduced through the condenser device 8. Thus, it is possible for the heat energy provided by the steam flowing out of the cooking chamber 2 to be transmitted via the condenser device 8 to the water conducted through the water supply 4 for generating steam. This achieves a particularly good energy balance of the cooking appliance.

In the simplest case, a capacitor device 8 can be provided by the fact that the water supply 4 at least in sections is in heat-transferring contact with the steam discharge 7. For this purpose, the water supply 4, for example, at least partially wound around the steam discharge 7.

In the embodiment shown, however, the capacitor device 8 comprises a storage device 9, which provides a suitable heat capacity for receiving the heat energy provided by the steam 5. Here is the Storage device 9 provided in the embodiment shown by a metal block 10, which is made of aluminum here.

In order to provide a sufficient heat capacity, an aluminum block with a weight of about 1 kg is selected in the embodiment shown. In other embodiments, heavier or lighter blocks of aluminum or other suitable metal, such as copper, may be used.

In addition to the energy recovery from the flow from the cooking chamber 2 steam 5 is achieved by the condenser 8 that the exiting through the steam outlet 6 steam 5 is condensed in the condenser 8 outweighed, so that the vapor pressure and the moisture arising from the cooking appliance 1 considerably reduced.

In order to dissipate the condensate or the resulting liquid formed in the condenser 8, a condensate discharge 11 is provided on the condenser device 8 in the embodiment shown. Such condensate removal 11 may be configured as an independent line system. In the exemplary embodiment shown, however, the condenser device 8 is arranged on the steam outlet 6 or in the steam discharge 7 in such a way that the condensate formed in the condenser device 8 flows back into the cooking chamber 2 via the steam discharge 7 and either evaporates again there or from there Wastewater disposal 14 is supplied. The condensate discharge 11 is thus integrated into the steam discharge 7 in the exemplary embodiment shown.

In FIG. 2 is a schematic diagram of a further cooking appliance according to the invention 1 shown. The basic structure of the cooking appliance 1 corresponds essentially to the previously described cooking appliance 1 according to FIG FIG. 1 ,

Again, water can be fed to an external steam generator 3 and evaporated. The steam 5 generated in the steam generator 3 is supplied via an outlet 21 and a line system 22 to the steam inlet 15 of the cooking chamber 2.

In the embodiment shown, the water used for evaporation is supplied to the steam generator 3 from a water supply 13. In other embodiments, the cooking appliance 1 or the steam generator 3 may also be connected to a fixed water connection.

Also in the embodiment shown here, the cooking chamber 2 comprises at least one steam outlet 6, via which steam 5 can be removed via the steam discharge 7 from the cooking chamber 2.

The water supply 4 and the steam discharge 7 are operatively connected to a condenser device 8, so that even with the cooking appliance 1 shown here, the advantages already described above can be achieved.

Furthermore, in FIG. 2 illustrated that in the water supply 4 and in the vapor discharge 7 bypass channels 18 are provided, which can be switched in the embodiment shown in each case via at least one multi-way valve 12. Thus, the water used for evaporation can be supplied either via the capacitor device 8 or directly to the steam generator 3. Furthermore, it is also possible to direct the steam discharge 7 via the condenser device 8 or to allow a direct discharge of the steam 5 from the cooking chamber 2.

Furthermore, in the illustrated embodiment, a purge line 16 is provided so that the steam generator 3 can be rinsed with water, this water used for rinsing can then be fed via the purge line 16 a sanitation 14. For this purpose, a multi-way valve 12 is provided in the line system 22, so that the steam generator 3 can be connected to either the steam inlet 15 or sewage disposal 14.

When operating the cooking appliances 1 according to the invention, the heat energy of the steam 5 emerging from the cooking chamber 2 is preferably at least partially transferred to the fresh water used for evaporation by means of the condenser device 8. As a result, the energy balance of the cooking appliance can be significantly improved. Thus, the water used for evaporation is preheated by the otherwise lost heat, so less energy must be used for evaporation. Furthermore, it is achieved that the discharged from the cooking chamber 1 moisture or vapor pressure is significantly reduced.

In order to enable a particularly effective heat transfer, the fresh water used for the evaporation is, depending on the configuration, only passed over the condenser device if a predetermined vapor content is already present in the cooking chamber 2. This ensures that the fresh water is only passed through the condenser device 8 when it has charged a certain heat capacity.

Furthermore, it is possible that at the end of a cooking process, the condenser device 8 and / or the steam generator 3 are rinsed with fresh water and thus cooled, so that a particularly rapid cooling of the cooking chamber and a particularly effective condensation of the steam 5 is achieved. The water used for rinsing may preferably be supplied to a sanitation so that the water used for rinsing is removed from the system.

LIST OF REFERENCE NUMBERS

1

Cooking appliance

2

oven

3

steam generator

4

water supply

5

steam

6

steam outlet

7

steam discharge

8th

capacitor device

9

memory device

10

metal block

11

condensate drain

12

Multi-way valve

13

water supply

14

sanitation

15

steam inlet

16

flushing line

17

bypass channel

18

line system

19

pump

20

line system

21

outlet

22

line system

23

sensor device

24

temperature sensor

25

Fan

26

condenser

27

Heat transfer device

100

Steamers

Claims (14)

Method for operating a cooking device (1), which has a cooking chamber (2), at least one steam generator (3) and at least one water supply (4) in connection to the steam generator (3), wherein the cooking chamber (2) by means of the steam generator (3 ) is heated with steam (5) and wherein the cooking chamber (2) comprises at least one steam outlet (6) which is connected to at least one steam discharge (7) of the cooking appliance (1), wherein the water intended for steam production at least temporarily over the Condenser device (8) is fed to the steam generator (3), characterized in that the water intended for steam production is supplied to the steam generator (3) via the condenser device (8) as a function of the steam content in the cooking chamber (2). Method for operating a cooking device (1), which has a cooking chamber (2), at least one steam generator (3) and at least one water supply (4) in connection to the steam generator (3), wherein the cooking chamber (2) by means of the steam generator (3 ) is heated with steam (5) and wherein the cooking chamber (2) comprises at least one steam outlet (6) which is connected to at least one steam discharge (7) of the cooking appliance (1), characterized in that for cooling the steam generator (3) and / or the standing in heat-conducting connection with the steam generator (3) cooking chamber (2) simultaneously with the shutdown of a heater of the steam generator (3) or immediately after switching off a heater of the steam generator, in particular within less than 30 seconds, preferably within less than 5 seconds, the steam generator (3) is so connected to the water supply (4) that the steam generator (3), in particular completely, is filled with water and / or is rinsed with water. Method according to one of the preceding claims, wherein the water, in particular fresh water, with which the steam generator (3) completely filled and / or flushed is at least 60 Kelvin colder than the steam produced by the steam generator (3) (5). Method according to one of the preceding claims, wherein the capacitor device (8) at least at the end of a cooking process is at least temporarily flushed with fresh water. Method according to one of the preceding claims, wherein the steam generator (3) is flushed with fresh water at least at the end of a cooking process. Method according to one of the preceding claims, wherein the water used for rinsing is supplied to a sanitation. Cooking appliance (1) comprising at least one cooking chamber (2), at least one steam generator (3) and at least one water supply (4) in connection to the steam generator (3), wherein the cooking chamber (2) by means of the steam generator (3) with steam (5 ) and wherein the cooking chamber (2) has at least one steam outlet (6) which is connected to at least one steam discharge (7), wherein the steam outlet (6) is connected to at least one condenser device (8) which is operatively connected to the Water supply (4) is,
characterized in that the cooking appliance (1) is arranged and configured to carry out a method according to claims 1 to 15. Cooking appliance (1) according to claim 7, wherein that the cooking appliance (1) is set up and provided to at least temporarily fill the steam generator (3) and / or the condenser device (8) completely with water, in particular fresh water, during a cooking process Rinse. Cooking appliance (1) according to claim 8 or 9, wherein the cooking appliance (1) is designed to fill or flush the steam generator (3) with water, the water supply (4) with a water supply (13) and / or with an outlet ( 21) of the steam generator (3) to connect. Cooking appliance according to one of claims 7 to 9, wherein the steam generator (3) in heat-conducting connection with a wall of the cooking chamber (2), in particular with the bottom of the cooking chamber (2) is designed and / or at least a portion of the steam generator (3) Condenser device (8) forms. Cooking appliance (1) according to one of claims 7 to 10, wherein the capacitor device (8) comprises at least one storage device (9). Cooking appliance (1) according to the preceding claim, wherein the storage device (9) at least partially by at least one metal block (10) is provided. Cooking appliance (1) according to one of claims 7 to 12, wherein the condenser device (8) is arranged directly on the steam outlet (6) and / or the condenser device (8) has at least one condensate discharge (11), which is preferably provided with a waste water disposal (14). connected is. Cooking appliance (1) according to one of claims 7 to 13, characterized in that in the water supply (4) and / or the vapor discharge (7) at least one bypass channel (17) is arranged.

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