EP3599421B1 - Cleaning system for cleaning the cooking area of a cooking appliance - Google Patents

Description

The invention relates to a cleaning system and a method for cleaning the cooking chamber of a cooking appliance with a ventilation device.

Devices for treating food, referred to below as cooking devices, are used for the thermal preparation of food and, depending on the application, include a large number of differently designed devices. Food, such as baked goods, is prepared in the cooking chamber of the cooking appliance.

As a result of cooking processes such as baking or steaming, the surfaces become more or less stubbornly soiled. Cleaning the cooking chamber plays an important role in preventing these dirt deposits and the associated growth of germs. The cleaning can take place mechanically, thermally or chemically according to the Sinner cycle. In the case of chemical cleaning, this can be done manually or automatically.

For automatic cleaning of the interior of baking ovens, nozzles are often used, which are either fixed or movable. There are a number of known solutions for this.

Rotatably mounted nozzles are used, for example, in DE 42 23 451 C2 mentioned. There is a spray nozzle in the middle of the ceiling of the furnace interior, which distributes liquid media in the interior. The reservoir for detergent or rinse aid is outside the cooking compartment. From the EP 1 147 731 B1 in turn, a more favorable positioning of the ceiling nozzle is known, which also covers the area around the fan wheel.

A completely different principle is used in the DE 10 2013 021 732 A1 suggested. There the active ingredient (cleaner) is in a disposable or reusable cartridge, which is itself designed as a ceiling nozzle. The treatment agent filled into the cartridge can be taken up as granules, powder, gel, block or liquid. The oven, in turn, has a water supply, such as a water tank or fresh water line, to feed water under pressure into the cartridge using a pump. The water is removed from the interior via a drain pipe.

In the DE 100 60 204 B4 two cartridges with cleaning agent and rinse aid are rinsed out via two nozzles and the resulting mixture via a circulation function in the oven's cooking chamber distributed.

A pump for transporting the detergent is, for example, in the DE 10 2015 103 673 A1 described. The pump is integrated in the cleaning tank, so that the suction and pressure lines are in the tank and any leakage that may occur will not cause any damage.

In the DE 10 2015 107 488 A1 a solid detergent is mixed with a solvent (water) in a reservoir by supplying kinetic energy - for example via a nozzle - in order to mix a liquid detergent. The cleaning agent is fed into the cooking chamber through a number of crossing points, which are connected to the reservoirs, with the disadvantage that there is a complex structure and, as a result, a more difficult process. Furthermore, after the cooking chamber has been cleaned, the used solution is discharged through a drain, the drain only serving as such.

In EP 2 634 492 A1 in turn, a sealed liquid detergent is introduced directly into a tank or into the interior of the cooking appliance.

The EP 0 801 271 A1 shows a spray nozzle with regard to the cleaning of an oven interior, which is connected directly to a pump, the pump conveying the cleaning agent from a tank.

The DE 199 50 920 C2 discloses a cleaning device with at least two rotor arms, each with at least one spray nozzle.

In the EP 0 652 405 B1 cleaning and rinsing liquid are connected via a node, so that there is a common central injection via a nozzle onto the fan wheel.

The DE 100 17 966 A1 describes a method and a device for cleaning the interior of a cooking appliance. The fan compartment is separated from the cooking compartment by air baffles. The liquids required for cleaning are introduced from a reservoir into the cooking chamber as a spray jet by means of a fan wheel via a spray nozzle. The spray jet in the blower room is directed against the flow of the blower wheel.

In the DE 10 2015 109 019 A1 discloses a cleaning device for commercial cooking appliances and a method for cleaning the same. For this purpose, the device comprises, among other things, a container for a cleaning agent. The cleaning agent, which has been liquefied and/or diluted by heating via a heating device and/or a fresh water supply, is fed into a storage tank via a rinsing nozzle. The cleaning solution is pumped by means of a pump Nozzles conveyed into the cooking chamber, whereby the used cleaning solution is drained off via an outlet sieve in the floor of the cooking chamber and, if necessary, can be used for a new run by being fed back into the storage tank. The disadvantage of this reuse of the cleaning solution is that it requires additional cleaning of the respective reservoirs, since dirt particles from the solution that has already been used can accumulate there. Furthermore, only one direction for the cleaning agent is specified by the outlet opening, so that the cleaning device is disadvantageously not flexible in the configuration of the cleaning process.

The disadvantage is that the nozzles used for cleaning, which are small in diameter and costly and have cross-sectional constrictions, clog very quickly, as a result of which there are frequent interruptions or maintenance work and continuous operation of the furnaces is not ensured.

The object is therefore to provide a system that overcomes the disadvantages of the prior art.

The aim is to provide a system for the chemical cleaning of cooking appliances that works reliably and is able to meter and distribute small amounts of fluid efficiently and thus ensures that the cooking chamber of a cooking appliance is cleaned as resource-savingly, economically and automatically as possible.

Furthermore, it should be possible to simply retrofit existing cooking appliances with such a system.

According to the invention, the object is achieved by a cleaning system and a method for cleaning a cooking chamber according to the independent claims. Advantageous developments of the invention are specified in the dependent claims.

A first aspect of the invention relates to a cleaning system for cleaning the cooking chamber of a cooking appliance with a ventilation device, having a supply system which includes at least a first supply device for water. According to the invention, the first supply device for water has a reservoir for water and, arranged in the flow direction of the water, an element for increasing the pressure and a water non-return valve. Furthermore, the cleaning system according to the invention comprises at least one second feed device for cleaning agents, which has a reservoir for cleaning agents and, arranged in the flow direction of the cleaning agent, a cleaning agent delivery unit and a cleaning agent non-return valve. The cleaning system according to the invention also has a Circulation circuit, the components of which are at least one connecting device which is in contact with a first opening of the cooking chamber and is designed as an outlet or inlet, at least one circulating device, at least one shut-off element which is designed in such a way that the connecting device and the return are fluidic connects or separates from each other, wherein in the case of a fluidic separation the obturator is designed such that it fluidly connects the connecting device to a drain, at least one return which is in contact with a second opening of the cooking chamber and is arranged along the vertical above the connecting device is and at least one distribution device. Furthermore, the cleaning system according to the invention comprises a control device with a computer program product, which is connected to the shut-off element in terms of information technology. According to the invention, the components of the circulation circuit are fluidically connected to one another by connecting elements. In terms of the invention, the first and second feed devices of the feed system open out in the direction of flow in the distributor device.

In order to be able to implement the cleaning system according to the invention, the cooking appliance must have features designed for this purpose. These features are well known and will only be described in more detail below where necessary.

For this purpose, the cooking appliance has a ventilation device, which advantageously makes it possible to implement the cleaning system according to the invention and the method according to the invention in the first place. The ventilation device serves to swirl the air in the cooking chamber during cooking. Advantageously, the ventilation device in the method according to the invention can also be used simultaneously to clean the cooking chamber by distributing liquid flowing into the cooking chamber via a return flow in the cooking chamber. In an alternative embodiment, the ventilation device can also be based on a different operating principle. The ventilation device can thus be designed as an injection device.

Furthermore, the cooking appliance must have at least one exhaust air device for drying. The exhaust air device can be designed as an exhaust air flap (also called vapor flap or vapor valve) or a motorized ball valve.

The cooking appliance also has a first opening. Furthermore, the cooking appliance has a second opening.

A further aspect of the invention relates to a cooking appliance which has a cleaning system according to the invention and a cooking chamber with a ventilation device.

In one embodiment, the cleaning system is at least partially integrated in the cooking appliance.

The cleaning system according to the invention has a feed system. The delivery system includes a large number of components. The feed system is not limited to the listed components. Rather, other components such as additional connectors, for example fittings or plug connectors, can also be installed in the respective feed devices.

In one embodiment, the components of the feed devices are fluidically connected to one another by connecting elements. In one embodiment, the connecting elements of the feed devices can be in the form of lines and can be selected from pipes or hoses. The tubes or hoses can be flexible or rigid.

In terms of the invention, the supply system comprises at least one first supply device for water.

According to the invention, the first supply device for water has a reservoir for water. The reservoir for water represents one of the two ends of the first feed device. The direction of flow of the water begins from here.

According to the invention, the first feed device has an element for increasing the pressure. The element for increasing the pressure directs the water from the water reservoir through the water non-return valve via the distributor device into the circulation circuit. The element for increasing the pressure is preferably arranged in the flow direction of the water.

In one embodiment, the element for increasing the pressure is designed as a water inlet valve or pressure accumulator.

In an alternative embodiment, the first feed device can have a water delivery device instead of an element for increasing the pressure. The water delivery device is designed as a pump, particularly preferably as a self-priming pump.

In a further alternative embodiment, the water delivery device is designed as a self-priming pump. In one embodiment, the water delivery device is designed as an oscillating piston pump, a membrane pump or a peristaltic pump. The water conveying device is located directly in the connecting element as a submersible unit the first feed device, for example in the tube. In a further alternative embodiment, the water delivery device is designed as a dosing unit.

In a further alternative embodiment, the reservoir for water is arranged in such a way that the water within the first supply device reaches the distribution device by the effect of gravity.

According to the invention, the first feed device has a water non-return valve. The water non-return valve is arranged in the direction of flow after the element for increasing the pressure.

In one embodiment, the first supply device has a water filter element which is arranged downstream of the water reservoir in the direction of flow. In a further embodiment, the water filter element is designed as a water filter.

According to the invention, the delivery system comprises at least one second delivery device for cleaning agents.

According to the invention, the second supply device for cleaning agents has a reservoir for cleaning agents. The reservoir for cleaning agent represents one of the two ends of the second feed device. The direction of flow of the cleaning agent starts from here.

The reservoir for cleaning agents preferably has a rinsing device.

According to the invention, the second feed device has a cleaning agent delivery unit. The cleaning agent delivery unit conveys the cleaning agent from the reservoir for cleaning agent through the cleaning agent non-return valve via the distributor device into the circulation circuit. The cleaning agent delivery unit is preferably arranged in the flow direction of the cleaning agent.

The cleaning agent delivery unit is preferably designed as a pump. In a very preferred embodiment, the cleaning agent delivery unit is designed as a self-priming pump. In one embodiment, the cleaning agent delivery unit is designed as an oscillating piston pump, diaphragm pump or peristaltic pump. In an alternative embodiment, the cleaning agent feed pump is located as an immersion unit directly in the connecting element of the second feed device, for example in the hose. In a further alternative embodiment, the cleaning agent delivery device is designed as a dosing unit.

In a further alternative embodiment, the reservoir for cleaning agent is arranged in such a way that the cleaning agent within the second feed device reaches the distributor device by the effect of gravity.

According to the invention, the second supply device has a cleaning agent non-return fitting. The cleaning agent non-return valve is arranged in the direction of flow after the cleaning agent delivery unit.

In one embodiment, the second supply device has a cleaning agent filter element which is arranged downstream of the cleaning agent reservoir in the flow direction. In a further embodiment, the cleaning agent filter element is designed as a cleaning agent filter.

The delivery system preferably comprises at least a third delivery device for rinse aid.

In a preferred embodiment, the third supply device for rinsing agent has a reservoir for rinsing agent. The reservoir for rinsing agent represents one of the two ends of the third feed device. The direction of flow of the rinsing agent starts from here.

In a preferred embodiment, the reservoir for rinsing agent has a rinsing device.

In a preferred embodiment, the third supply device has a rinse-aid delivery unit. The rinse aid delivery unit directs the rinse aid from the reservoir for rinse aid through the rinse aid non-return valve via the distributor device into the circulation circuit. In a further preferred embodiment, the rinse aid delivery unit is arranged in the flow direction of the rinse aid.

In a preferred embodiment, the rinse aid delivery unit is designed as a pump. In a very preferred embodiment, the rinse aid delivery unit is designed as a self-priming pump. In one embodiment, the rinse aid delivery unit is designed as an oscillating piston pump, membrane pump or hose pump. In an alternative embodiment, the rinse aid feed pump is located as an immersion unit directly in the connecting element of the third feed device, for example in the hose. In a further alternative embodiment, the rinse aid delivery device is designed as a dosing unit.

In a further alternative embodiment, the reservoir for rinsing agent is arranged in such a way that the rinsing agent within the third supply device reaches the distribution device by the effect of gravity.

In a preferred embodiment, the third supply device has a non-return valve for rinse aid. The rinse aid non-return fitting is arranged after the rinse aid delivery unit in the direction of flow.

In one embodiment, the third supply device has a rinse-aid filter element, which is arranged after the reservoir for rinse-aid in the direction of flow. In a further embodiment, the rinse aid filter element is designed as a rinse aid filter.

In a preferred embodiment, the supply system comprises at least a fourth supply device for descaler.

In one embodiment, the fourth supply device for descaler has a reservoir for descaler. The reservoir for descaler represents one of the two ends of the fourth feed device. The flow direction of the descaler starts from here.

In one embodiment, the reservoir for descaler has a rinsing device.

In one embodiment, the fourth feed device has a descaler delivery unit. The descaler delivery unit directs the descaler from the descaler reservoir through the descaler non-return valve via the distribution device into the circulation circuit. In a further embodiment, the descaler delivery unit is arranged in the flow direction of the descaler.

In one embodiment, the descaler delivery unit is designed as a pump. In a very preferred embodiment, the descaler delivery unit is designed as a self-priming pump. In one embodiment, the descaler delivery unit is designed as an oscillating piston pump, membrane pump or peristaltic pump. In an alternative embodiment, the descaler feed pump is located as an immersion unit directly in the connecting element of the fourth feed device, for example in the hose. In a further alternative embodiment, the descaler delivery device is designed as a dosing unit.

In a further alternative embodiment, the reservoir for descaler is arranged in such a way that the descaler within the fourth feed device reaches the distributor device by the effect of gravity.

In one embodiment, the fourth feed device has a descaler non-return valve. The descaler non-return valve is arranged in the direction of flow after the descaler delivery unit.

In one embodiment, the fourth supply device has a descaler filter element, which is arranged after the reservoir for descaler in the direction of flow. In a further embodiment, the descaler filter element is designed as a descaler filter.

The media introduced into the cleaning system according to the invention are used for cleaning and are either in liquid or solid form. Irrespective of their initial state of aggregation, these media always arrive in the cooking chamber in liquid or gel-like form, with the gel-like form having a low, medium or high viscosity form. The state of aggregation in liquid or gel-like form is referred to below as "liquids in the cooking chamber" for the sake of simplicity. The media properties mentioned below relate to all types of media used, namely cleaning agents, rinse aids and descalers, although this list is not exhaustive. The known properties apply to the properties of water.

In one embodiment, the media have alkaline, neutral or acidic properties or pH values. In this respect, the corresponding properties of the components of the cleaning system, such as the materials of the reservoirs or the selection of the connecting elements, are advantageously also adapted, designed and selected.

In one embodiment, the water is in the form of tap water and is used to supply fresh water to the cleaning system according to the invention.

In one embodiment, the cleaning agent, the rinse aid and/or the descaler is in the form of a liquid. In a further embodiment, the cleaning agent, the rinsing agent and/or the descaler is designed ready for use.

In a preferred embodiment, the cleaning agent is highly alkaline. In a further preferred embodiment, the rinse aid is acidic or neutral. In a further preferred embodiment, the descaler is acidic.

In one embodiment, the cleaning agent, the rinse aid and/or the descaler is in the form of a solid. The solid can be designed as a tab, for example.

In the case of solids as media, the reservoir or reservoirs, which contains the solid, preferably has a rinsing device. Both the reservoir for cleaning agent and the reservoir for rinse aid as well as the reservoir for descaler preferably have such a flushing device. The rinsing device advantageously causes the solid to be dissolved into a liquid or gel-like aggregate state. In one embodiment, the flushing device is designed in the same way for all three types of media, for example as a water nozzle.

In the case of solids as media in solid form, the reservoir or reservoirs containing the solid corresponds to a cartridge and is therefore no longer designed as a tank. The cartridge is flushed out by the flushing device. As a result, the solid is dissolved and can be conveyed in liquid form to the distributor device by the corresponding second, third or fourth feed device. In one embodiment, with solids as the media, the corresponding feed devices have no conveyor units, since these are not required for this purpose.

In a further embodiment, the feed system comprises more than two, three or four feed devices, as a result of which other media required for the cleaning process can advantageously be added.

In one embodiment, in the case of an activated water supply device, the other supply devices are blocked by the distributor device. This can also be used analogously for other activated feed devices. In an alternative embodiment, more than one feed device can be activated at the same time and deliver media in the distribution device.

Unless otherwise specified, the properties listed below relate to all of the identically designed components of the feed devices (e.g. all reservoirs or all non-return fittings). In each case, only one component or at least one component or all components can have these properties.

In one embodiment, the reservoirs are internal, ie arranged within the cleaning system. In a further embodiment, the reservoirs have control devices which are designed as float switches or suction lances. In an additional embodiment, the reservoirs have level sensors.

In one embodiment, the reservoirs are designed as tanks or containers. In a further embodiment, the reservoirs are designed as adjustable inflow fittings. For example, the reservoir for water can be designed as a faucet or water pipe to which the first feed device of the cleaning system according to the invention can be connected.

In one embodiment, the non-return fittings are designed as non-return valves. In a further embodiment, the non-return fittings are designed as spring-loaded non-return valves.

Particles present in the media are advantageously prevented from entering the circulation circuit by the filter elements.

The cleaning system according to the invention has a circulation circuit.

The recirculation circuit includes a large number of components. According to the invention, the components of the circulation circuit are fluidically connected to one another by connecting elements. The circulation circuit is not limited to the listed components.

In one embodiment, all of the components of the circulation circuit are located on a gradient, so that the cooking chamber can advantageously be completely emptied.

According to the invention, the circulating circuit comprises at least one connecting device as a component.

According to the invention, the connecting device is in contact with a first opening of the cooking chamber. The connecting device is preferably connected to the first opening of the cooking chamber in a material or non-positive manner.

Depending on the intended use, the connecting device is designed as an outlet or inlet.

In one embodiment, the connecting device is fastened in the first opening of the cooking space, for example it is welded to it.

In one embodiment, the connecting device is designed as a funnel or tube or hose, with the tube or hose being flexible or rigid. In a preferred embodiment, the connecting device is a sieve that protrudes into the cooking space. A square profile with a socket connects to the screen vertically downwards and backwards, which in turn is connected to a hose or T-piece, which then leads to the shut-off device.

According to the invention, the circulating circuit comprises at least one circulating device as a component. The circulation device ensures the continuous movement of the media in the circulation circuit. In one embodiment, the circulating device is designed in such a way that different conveying directions can be implemented.

In one embodiment, the circulating device is designed as a circulating pump or drain pump.

According to the invention, the circulating circuit comprises at least one shut-off element as a component.

According to the invention, the shut-off element is designed in such a way that it fluidically connects or separates the connecting device and the return flow. The connection or separation takes place via the outlets of the shut-off element, which are controlled accordingly by the control device. In one embodiment, in the case of a fluidic connection, at least two outlets are open, so that the connecting elements connected to them are in fluidic contact with one another. In a further embodiment, in the case of a fluidic separation, at least one outlet is closed, so that the connecting element connected to it is fluidically separated from the other outlets of the shut-off element and thus from the other connecting elements of the circulation circuit.

In the context of the invention, in the case of a fluidic separation, the shut-off element is designed in such a way that it fluidly connects the connecting device to a drain. A fluidic connection is created between the connecting element that is arranged between the connecting device and the shut-off element and the connecting element that is located between the shut-off element and the drain is arranged, made.

In one embodiment, the shut-off element is designed as a shut-off valve, preferably as a multi-way valve, ball valve, plug valve, piston valve or cylinder valve. But any other equivalent solution can be used as a shut-off device.

In the case of a multi-way valve, this is designed as a 3-way valve or 2-way valve.

In one embodiment, the shut-off device has an actuator. The shut-off element is electrically driven, for example, by a motor. The actuator of the shut-off device is controlled by the control device.

In a preferred embodiment, the at least one shut-off element has at least three outlets. The outlets correspond to settings that regulate and control the fluidic connections in the circulation circuit. The outlets of the shut-off element advantageously have a sufficiently large diameter so that they cannot be blocked by particles present in the media.

In preferred embodiments, a first outlet is connected to the drain via a connecting element. In further preferred embodiments, a second outlet is connected to the connecting device or the circulation device or the distribution device via a connecting element. In further preferred embodiments, a third outlet is connected to the circulation device or the distributor device or the return via a connecting element. It is conclusive that at the end of each Cleaning step, in the case of the connection of the second outlet with the circulating device, a connection of the third outlet with the circulating device is not possible. This applies analogously to the distribution device. Advantageously, the desired connecting elements can be emptied in this way. During the cleaning steps themselves, all connecting elements and components of the circulation circuit are fluidically connected to one another via open outlets.

In a preferred embodiment, the at least one shut-off element for fluidically connecting the connecting device to the return is designed in such a way that the second and third outlets are open and the first outlet is closed. In a further preferred embodiment, the at least one shut-off element for the fluidic separation of the connecting device from the return is designed in such a way that the first and second outlets are open and the third outlet is closed.

In one embodiment, the at least one shut-off element comprises at least one multi-way valve, which has at least three outlets, or at least two multi-way valves, which each have at least two outlets. In the case of several multi-way valves or other components with the same effect, these are connected in series or in parallel.

According to the invention, the circulation circuit comprises at least one return as a component. The return is also referred to as a return pipe and is designed as such. Within the meaning of the invention, the return pipe is a classic hollow cylinder and has a constant diameter without a narrowing of the cross section (as, for example, in the case of a nozzle).

According to the invention, the return is in contact with a second opening of the cooking chamber. The return is preferably connected to the second opening of the cooking chamber in a material or non-positive manner. In one embodiment, the return points into the cooking space, preferably in the direction of the ventilation device.

In one embodiment, the return is designed as fixed tubing, such as a bent metal tube. In a further embodiment, the return is designed as a flexible hose.

According to the invention, the return is arranged along the vertical above the connecting device. This means that the second opening of the cooking chamber is also arranged vertically above the first opening. The vertical refers to the position and direction designation, as it is also used in anatomy, namely along the line from the crown to the sole, when viewed from an upright user of the cooking appliance runs out In one embodiment, the first opening is arranged in the floor, in the rear wall and in the side walls of the cooking chamber. In a further embodiment, the second opening is arranged in the ceiling, the rear wall and the side walls of the cooking space.

According to the invention, the circulating circuit comprises at least one distributor device as a component. The distribution device is also referred to as the vaccination point. According to the invention, the distribution device corresponds to a mixing and dosing device or transfer point for the media from the feed system into the circulation circuit. The distribution device does not correspond to a container or reservoir for the (temporary) storage of cleaning agent and/or water. Rather, the cleaning agents and/or the water are passed on directly into the circulation circuit by the distribution device without being (temporarily) stored in the distribution device. In one embodiment, the distribution device is designed in such a way that even small amounts of liquid can be fed into the circulation circuit.

According to the invention, the first, second and third feed device of the feed system each open into the distribution device in the direction of flow. The respective mouth of the corresponding feed device occurs with that end which is arranged on the opposite side to the respective reservoir (and thus the respective first end of the feed device). In principle, all feed devices of the feed system end in the flow direction in the distributor device.

In one embodiment, the distributor device has at least four connections, with three connections or four connections (in the case of a fourth feed device) opening into the respective feed devices and one connection opening into the circulation circuit.

In embodiments, the distributor device is designed as a cross distributor or as two T-pieces with a cross distributor.

In one embodiment, the circulating device, shut-off element and distributor device can be arranged flexibly in the circulating circuit and do not have a preferred position.

In one embodiment, the drain is designed as a pipe or hose, flexible or rigid. In further embodiments, the outflow in the direction of flow of the mixture used is followed by a tank which is connected either to a free outlet in the ground or to a lifting system.

The cleaning system according to the invention has a control device with a computer program product.

According to the invention, the control device is connected to the shut-off element in terms of information technology. In a further preferred embodiment, the control device is connected to all components of the cleaning system according to the invention in order to control them and regulate the cleaning process. For this purpose, all components of the cleaning system according to the invention also have a wired or wireless connection to the control unit.

In one embodiment, the information technology connection between the control device and the shut-off element is wire-based or wireless. The shut-off element is actuated by the control device in order to regulate the flow streams in the circulation circuit by opening or closing individual outlets of the shut-off element.

In one embodiment, the control device is mounted within the cleaning system on the door of the cooking appliance.

In a preferred embodiment, the computer program product includes instructions that cause the cleaning system according to the invention to carry out the method steps according to the invention. In one embodiment, the computer program product includes the cleaning program. This corresponds to the algorithm to be run, which is individually oriented to the conditions of the cooking chamber.

In one embodiment, at least some of the components and/or connecting elements are sterile.

In embodiments, cooking devices include stoves such as electric stoves, combination cookers and baking ovens, which are designed as in-store baking ovens, deck baking ovens or rack ovens, although the list is not exhaustive.

In embodiments of the invention, the cooking chamber is also referred to as a treatment chamber, baking chamber or interior.

1. a) Reinigen mit Wasser und Reinigungsmittel,
2. b) Spülen mit Wasser, und
3. c) Trocknen des Garraums.

A further aspect of the invention relates to a method for cleaning the cooking chamber of a cooking appliance using the cleaning system according to the invention. Within the meaning of the invention, the method comprises at least the following steps:

1. a) cleaning with water and detergent,
2. b) rinsing with water, and
3. c) Drying of the cooking chamber.

The steps are also referred to as cleaning or process steps. In one embodiment, steps a), b) and c) are carried out one after the other in chronological order. In an alternative embodiment, however, the steps can be combined with one another, carried out several times in succession or in a different order, as required.

In a preferred embodiment, each method step is repeated as often as desired. The repetition includes both the multiple repetition of an individual process step in succession or the repetition of the entire sequence of steps a) to c) or a) and b) or a) and c) or b) and c). Advantageously, cleaning can be adjusted individually depending on the degree of soiling of the cooking chamber.

In a preferred embodiment, the computer program product of the control device includes instructions which cause at least steps a) to c) to be carried out.

In a preferred embodiment, the method according to the invention includes cleaning the cooking chamber with cleaning agent and water.

In a preferred embodiment, the cleaning agent is conveyed from the second feed device by the cleaning agent delivery unit via the distributor device into the circulation circuit. Together with water, a water-cleaning agent mixture is formed, which is conveyed into the cooking chamber through the connecting device. After the cleaning agent has been introduced, the water is fed into the circulation circuit as described in step a). In an alternative embodiment, the water from a previous cleaning stage is already in the circulation circuit.

This preferably takes place until a characteristic fill level is reached at which the circulation device is activated and the water/cleaning agent mixture is conveyed from the connection device via the connection elements of the circulation circuit through the return to the ventilation device of the cooking chamber. A characteristic fill level is understood to mean a desired fill level in the cooking chamber at which there is a volume sufficient for continuous circulation. In one embodiment, this volume is specified as a value by the control device. Typically, this volume is in the range of 1.5L to 4.5L.

The water-cleaning agent mixture is distributed in the cooking chamber by the ventilation device.

After cleaning, the used water-cleaning agent mixture flows through the connection device into the drain. The water-cleaning agent mixture used corresponds to dirty water.

In a preferred embodiment, cleaning step a) is followed by a rinsing step with water as cleaning step b), with water flowing from the first supply device via the distributor device into the circulation circuit until the connecting elements are completely filled, so that further water flowing into the circulation circuit flows through the Return flows to the ventilation device of the cooking chamber and is distributed there. In an alternative embodiment, the pre-rinsing is carried out by radial fan steam, in which liquid water flows from a further opening in the cooking chamber directly onto the ventilation device and is distributed by it. After cleaning, the used water flows through the connection device into the drain. The water used corresponds to dirty water.

In a further alternative embodiment, liquid water is directed to a heater outside the cooking chamber in an external steam generator of the cooking appliance, whereby steam is generated.

In a preferred embodiment, the method according to the invention comprises, as step c), the drying of the cooking chamber, which follows the cleaning and rinsing of the cooking chamber.

In one embodiment, a heating element in the cooking chamber of the cooking appliance is switched on or off during drying, depending on the deviation between the desired and actual temperature, and the ventilation device is activated.

In one embodiment, a pre-rinsing of the cooking chamber takes place as a further method step. The pre-rinsing takes place before process step a), the cleaning. The pre-rinse is used to moisten the surfaces of the cooking chamber and thus helps to make the cleaning more effective. In addition, large loose dirt particles are removed.

In a preferred embodiment, the pre-rinsing takes place with water, with water flowing from the first supply device via the distributor device into the circulation circuit until the connecting elements are completely filled, so that further water flowing into the circulation circuit flows through the return to the ventilation device of the cooking chamber and is distributed there becomes. In an alternative embodiment, the pre-rinsing is carried out by radial fan steam, in which liquid water flows from a further opening in the cooking chamber directly onto the ventilation device and is distributed by it. In another alternative embodiment, liquid water is directed to a heater outside of the cooking chamber in an external steam generator of the cooking appliance, whereby steam is generated.

In a further embodiment, a further rinsing step with water takes place, which is also referred to as intermediate rinsing and preferably takes place between cleaning step a and cleaning step b). Intermediate rinsing runs in the same way as pre-rinsing. In a further embodiment, the intermediate rinsing can be carried out after each cleaning stage or as required. In one embodiment, both during pre-rinsing and intermediate rinsing, the liquid in the cooking chamber is distributed by kinetics, in that excess static pressure is dissipated.

In a preferred embodiment, the method according to the invention includes rinsing the cooking chamber with rinsing agent and water.

In one embodiment, the cleaning step of rinsing has the same sequence as step a) of cleaning—except that the rinsing agent is used instead of the cleaning agent.

The rinsing preferably follows the cleaning of the cooking chamber with water and cleaning agent.

In a preferred embodiment, the rinsing agent is conveyed from the third supply device by the rinsing agent delivery unit via the distribution device into the circulation circuit. Together with water, a water-rinse agent mixture forms, which is conveyed through the connecting device into the cooking chamber. In this case, after the rinse aid has been introduced, the water is routed into the circulation circuit as described in step a). In an alternative embodiment, the water from a previous cleaning stage is already in the circulation circuit.

This preferably takes place until a characteristic fill level is reached at which the circulation device is activated and the water-rinse aid mixture is conveyed from the connection device via the connection elements of the circulation circuit through the return to the injection device of the cooking chamber. The characteristic filling level during rinsing also corresponds to that filling level during cleaning.

The water-rinse aid mixture is distributed in the cooking chamber by the injection device.

After cleaning, the mixture of water and rinse aid used flows through the connection device into the drain. The water-rinse aid mixture used corresponds to this neutralized rinse water.

In a preferred embodiment, decalcification is carried out as a further cleaning step. In this decalcification cleaning step, a decalcifier is conveyed from the fourth feed device by the decalcifier delivery unit via the distribution device into the circulation circuit. In an alternative embodiment, the descaler can be added as needed, depending on the requirements for cleaning the cooking chamber.

Together with water, which is either already in the circulating circuit or is being conveyed there, a water/decalcifier mixture is formed, which is conveyed into the cooking chamber through the connecting device.

This preferably takes place until a characteristic fill level is reached, at which point the circulating device is activated and the water-decalcifier mixture is conveyed from the connecting device via the connecting elements of the circulating circuit through the return to the injection device of the cooking chamber.

The mixture of water and descaler is distributed in the cooking chamber by the injection device.

After cleaning, the used water-descaler mixture flows through the connection device into the drain.

In a preferred embodiment, the at least one shut-off element fluidically connects the connecting device to the circulation device at the beginning and during step a) by activation of the control device. The connecting device acts as an inlet.

In a preferred embodiment, the at least one shut-off element fluidically separates the connecting device at b) and at the end of step a) from the circulation device by the actuation of the control device. The connecting device acts as a drain.

It is essential to the invention that the connecting device has a dual function, namely by acting as an inlet and outlet.

In one embodiment, the at least one shut-off element fluidically connects the connecting device to the circulation device during pre-flushing and intermediate flushing by activation of the control device. The connecting device acts as an inlet.

In a preferred embodiment, the cleaning system according to the invention is used to clean the cooking chamber of a cooking appliance. All conceivable embodiments of cooking appliances can be used for the system according to the invention.

In a further preferred embodiment, the method according to the invention is used to clean the cooking chamber of a cooking appliance. The process according to the invention corresponds to a chemical cleaning process.

In a further preferred embodiment, the computer program product, which is used to carry out the method, is used to clean the cooking chamber of a cooking appliance.

In a further preferred embodiment, the control device on which the computer program product according to the invention is stored is used to clean the cooking chamber of a cooking appliance.

In a preferred embodiment, the method according to the invention is used to clean the cooking chamber of a cooking appliance.

Advantageously, the cleaning system according to the invention does not require any additional ventilation of the circulation line, since the connecting device has a dual function as an outlet and an inlet. The fill level is thus generated via the connecting device.

Even with small amounts of liquid, which is advantageously more resource-saving and economical, this double function, combined with the efficiently working distribution device, creates a stable circulation circuit. Less water, detergent and rinse aid is required to clean the cooking compartment. An associated major advantage of the cleaning system according to the invention is the omission of expensive nozzles with cross-sectional constrictions. Also, due to the passages of the components in the feed system and circulation circuit, which are designed to be large compared to the nozzle channels, they are advantageously less susceptible to larger particles, which could lead to blockages in the line cross sections. Due to the separation into different feed devices, the use of combination cleaning agents is no longer necessary, so that the cooking chamber can be cleaned more efficiently.

Furthermore, the cleaning system according to the invention advantageously does not require an additional drain valve, since this function is implemented by the shut-off element by opening or closing the outlets.

Due to the low consumption, e.g. of highly alkaline cleaning and rinsing agents per cleaning cycle, the user, e.g be carried out at longer intervals. Another advantage is that the user no longer comes into contact with the hazardous substances.

In one embodiment, the cooking appliances can be subsequently upgraded or retrofitted with the cleaning system according to the invention. The cleaning system according to the invention can thus advantageously be installed on all ovens which have at least one ventilation device, a first and second opening and an exhaust air device.

example

The invention will be explained in more detail below using an exemplary embodiment. The exemplary embodiment relates to a cleaning system for cleaning the cooking chamber of a cooking appliance with a ventilation device and is intended to describe the invention without restricting it.

Fig. 1

eine schematische Skizze des erfindungsgemäßen Reinigungssystems mit drei Zuführeinrichtungen.

The invention is explained in more detail with reference to a drawing. while showing

1

a schematic sketch of the cleaning system according to the invention with three feeders.

figure 1 shows a schematic sketch of the cleaning system 1 according to the invention with three feed devices (not true to scale). The cleaning device 1 is integrated in a cooking device 2 designed as a baking oven with a cooking chamber 3 . The delivery system of the cleaning system 1 has three delivery devices. In the direction of flow, the first supply device comprises a reservoir for water 4 designed as a water tank, a water filter element 7 designed as a water filter, an element for increasing the pressure 10 designed as a water inlet valve and a water non-return fitting 11 designed as a spring-loaded water non-return valve In the direction of flow, a reservoir for cleaning agent 5 designed as a cleaning agent tank, a cleaning agent filter element 8 designed as a cleaning agent filter, a cleaning agent delivery unit 12 designed as a self-priming cleaning agent pump, and a cleaning agent non-return fitting 13 designed as a spring-loaded cleaning agent check valve as Rinse aid tank designed reservoir for rinse aid 6, a rinse aid filter element 9 designed as a rinse aid filter, a rinse aid delivery unit 14 designed as a self-priming rinse aid pump and a rinse aid non-return fitting 15 designed as a spring-loaded rinse aid check valve.

In their direction of flow, the three feed devices open into a distribution device 16 designed as a cross-distributor. The distribution device 16 is a component of the circulation circuit. This also includes a connecting device 23 designed as a sieve, to which in the present example a first connecting element 17 designed as a hose is connected, which in turn is connected to a second outlet 26 of the shut-off element 24 designed as a motorized ball valve. The obturator 24 has three outlets. The first outlet 25 of the obturator 24 is connected to a drain (not shown in the figure) via a hose in the direction of flow. The third outlet 27 of the shut-off element 24 is connected to a circulating device 21 embodied as a circulating pump via a second connecting element 18 embodied as a hose. The circulation device 21 is in turn connected to the distributor device 16 via a third connecting element 19 designed as a hose. The distributor device 16 is connected in the circulation circuit via a fourth connecting element 20 embodied as a hose to a return 22 embodied as a return pipe. The return 22 is non-positively connected to a second opening on the side wall of the cooking chamber 3 and points into the cooking chamber 3 to the ventilation device 29 designed as a fan wheel. The cooking chamber 3 also has a heating element 30 designed as a ring heating element, with the heating element 30 and the ventilation device 29 are covered by a hot air baffle 31 in order not to be visible to the user.

The connecting device 23 is open for pre-rinsing. The control device (not shown in the figure) regulates that the first outlet 25 and the second outlet 26 of the shut-off element 24 are open and thus fluidly connected to one another and that the third outlet 27 of the shut-off element 24 is blocked and thus fluidly closed. In this setting, any water that occurs in the cooking chamber 3 can flow away in the direction of flow 28 via the connecting device 23 . If the pressure increase element 10 is actuated, tap water flows from the water reservoir 4 via the water filter element 7 through the water non-return valve 11 into the distributor device 16, from where it is distributed in the circulation circuit via the connecting elements 18-20. If the connecting elements 18-20 are completely filled with tap water, the excess new tap water flowing in is pressed out through the return 22 in the direction of the ventilation device 29 and injected into the cooking chamber 3. In this way, fresh water is supplied. The connections from the reservoir for cleaning agent 5 and from the reservoir for rinsing agent 6 are shut off by the respective cleaning agent non-return fitting 13 and rinsing agent non-return fitting 15 . Any water that occurs in the cooking chamber 3 flows out via the connecting device 23, which acts as a drain.

For cleaning stage a), the connecting device 23 is initially closed. As a result, the second outlet 26 and the third outlet 27 of the shut-off element 24 are fluidically connected to one another and the first outlet 25 of the shut-off element 24 is blocked. As a result, all liquids injected up to that point remain in the circulation circuit. Cleaning agent from the reservoir for cleaning agent 5 is conveyed through a cleaning agent filter element 8 via a cleaning agent delivery unit 12 and cleaning agent non-return valve 13 into the distributor device 16 and subsequently into the third connecting element 19 . The pre-supplied detergent is then flushed with tap water, which was still in the circulation circuit from the pre-rinse, together via the connecting device 23, which acts here as an inlet, into the cooking chamber 3 through the circulating device 21, so that a level slowly builds up in the cooking chamber 3. If there is sufficient water/cleaning agent mixture, the water/cleaning agent mixture is sucked back into the circulation circuit via the connection device 23 by the circulating device 21 and transported from there via the return 22 and the ventilation device 29 into the cooking chamber 3 . The ventilation device 29 distributes the water/cleaning agent mixture throughout the cooking chamber 3.

After a sufficiently long period of time, the circulation is ended by turning off the circulation device 21 and draining the dirty water by actuating the shut-off valve by opening the first outlet 25 and the second outlet 26 and blocking the third outlet 27 . The dirty water flows in the direction of drain 28 from.

Then there is an intermediate rinse, which has the same steps as the pre-rinse.

At the start of rinsing as cleaning stage b), the connecting device 23 is closed. For this purpose, the second outlet 26 and the third outlet 27 of the shut-off element 24 are fluidly connected to one another and the first outlet 25 of the shut-off element 24 is blocked. The element for increasing the pressure 10 is controlled by the control device. The rinse aid delivery unit 14 is activated and delivers a quantity of rinse aid from the rinse aid reservoir 6 via the rinse aid filter element 9 and the rinse aid non-return valve 15 to the distributor device 16. The element is then in turn switched to pressure increase 10 and the rinse aid, together with the tap water remaining in the circulation circuit from the previous intermediate rinsing, is introduced into the cooking chamber 3 via the connecting elements 17-19 via the connecting device 23, which acts as an inlet. When the desired fill level is reached, the element for increasing the pressure 10 is de-energized. Next, the circulating device 21 is activated. This sucks in the water-rinse aid mixture and conveys it via the return 22 back to the ventilation device 29 located on the rear wall of the cooking chamber 3. The ventilation device 29 distributes the water-rinse aid mixture throughout the cooking chamber 3. After a sufficiently long period, the Circulation ended by turning off the circulating device 21 and draining the neutralized rinsing water by actuating the shut-off valve, by opening the first outlet 25 and the second outlet 26 and blocking the third outlet 27 .

The last cleaning step c) includes the drying of the cooking chamber 3. By opening an exhaust air flap (not shown in the figure, is at the back of the oven), the residual liquid on the surface can evaporate and a dry, cleaned and hygienically safe surface remains. During drying, the heating element 30 is cycled and the ventilation device 29 is activated.

Reference sign

1

cleaning system

2

cooking appliance

3

cooking chamber

4

reservoir for water

5

Reservoir for detergent

6

Rinse aid reservoir

7

water filter element

8th

Detergent filter element

9

Rinse aid filter element

10

Pressure increase element

11

water check valve

12

Detergent delivery unit

13

Detergent non-return valve

14

Rinse aid delivery unit

15

Rinse aid non-return valve

16

distribution device

17

First fastener

18

Second connector

19

Third connector

20

Fourth fastener

21

circulating device

22

return

23

connecting device

24

shut-off device

25

First exit of the shut-off device

26

Second exit of the shut-off device

27

Third exit of the shut-off device

28

Direction of flow of the used water, water/detergent mixture or water/rinse aid mixture to the drain

29

ventilation device

30

radiator

31

hot air baffle

Claims (13)

1. Cleaning system (1) for cleaning the cooking chamber (3) of a cooking appliance (2) having a ventilation device (29), comprising

   - a supply system, comprising

   ∘ at least a first supply device for water, the device having a reservoir for water (4) and, arranged in the direction of flow of the water, an element for increasing the pressure (10) and a water check valve (11),

   ∘ at least a second supply device for cleaning agent, the device having a reservoir for cleaning agent (5) and, arranged in the direction of flow of the cleaning agent, a cleaning agent conveying unit (12) and a cleaning agent check valve (13),

   - a circulation circuit which comprises, as components,

   ∘ at least one connection device (23) which is in contact with a first opening of the cooking chamber (3) and is designed as an outlet or inlet,

   ∘ at least one return pipe (22) which is in contact with a second opening of the cooking chamber (3) and is arranged along the vertical above the connection device (23),

   ∘ at least one circulation device (21),

   ∘ at least one shut-off member (24) which is designed in such a way that it fluidically connects the connection device (23) and the return pipe (22) to one another or separates them from one another, wherein in the event of a fluidic separation, the shut-off member (24) is designed in such a way that it fluidically connects the connection device (23) to a drain,

   ∘ at least one distribution device (16) which is designed as a mixing and metering device,

   - at least one control device having a computer program product, which device is connected to the shut-off member (24) using information technology,

   wherein the components of the circulation circuit are fluidically connected to one another by means of connection elements (17, 18, 19, 20), and wherein the first and second supply devices of the supply system open in the distribution device (16) in the direction of flow.
2. Cleaning system (1) according to claim 1, characterised in that the cleaning agent conveying unit (12) is designed as a pump.
3. Cleaning system (1) according to either claim 1 or claim 2, characterised in that the reservoir for cleaning agent (5) has a rinsing device.
4. Cleaning system (1) according to any of claims 1 to 3, characterised in that the supply system further comprises at least a third supply device for rinse agent, which device has a reservoir for rinse agent (6) and, arranged in the direction of flow of the rinse agent, a rinse agent conveying unit (14) and a rinse agent check valve (15), the third supply device of the supply system opening in the distribution device (16) together with the first and second supply devices in the flow direction.
5. Cleaning system (1) according to any of claims 1 to 4, characterised in that the at least one shut-off member (24) has at least three outlets (25, 26, 27), a first outlet (25) being connected to the drain via a connection element, a second outlet (26) being connected to the connection device (23) or to the circulation device (21) or to the distribution device (16) via a connection element (17, 18, 19), and a third outlet (27) being connected to the circulation device (21) or to the distribution device (16) or to the return pipe (22) via a connection element (18, 19, 20).
6. Cleaning system (1) according to claim 5, characterised in that the at least one shut-off member (24), for fluidically connecting the connection device (23) to the return pipe (22), is designed in such a way that the second and third outlets (26, 27) are open and the first outlet (25) is closed, and, for fluidically separating the connection device (23) from the return pipe (22), is designed in such a way that the first and second outlets (25, 26) are open and the third outlet (27) is closed.
7. Cooking appliance (2) having a cleaning system (1) according to any of claims 1 to 6 and a cooking chamber (3) having a ventilation device (29).
8. Method for cleaning the cooking chamber (3) of a cooking appliance (2) by means of a cleaning system (1) according to any of claims 1 to 6, at least comprising the steps of:

   a) cleaning with water and cleaning agent, wherein the cleaning agent is conveyed out of the second supply device through the cleaning agent conveying unit (8) via the distribution device (16) into the circulation circuit and, together with water as a water-cleaning agent mixture, is conveyed through the connection device (23) into the cooking chamber (3) until a characteristic fill level is reached, at which level the circulation device (21) is activated and the water-cleaning agent mixture is conveyed out of the connection device (23) via the connection elements (17, 18, 19, 20) of the circulation circuit through the return pipe (22) to the ventilation device (29) of the cooking chamber (3), where the water-cleaning agent mixture is distributed in the cooking chamber (3) and, after cleaning, the used water-cleaning agent mixture flows through the connection device (23) into the drain,

   b) rinsing with water, wherein water flows out of the first supply device via the distribution device (16) into the circulation circuit until the connection elements (17, 18, 19, 20) are completely filled with water, so that further water flowing into the circulation circuit flows through the return pipe (22) to the injection device of the cooking chamber (3) and is distributed there, and

   c) drying the cooking chamber (3),

   wherein the at least one shut-off member (24) fluidically connects the connection device (23) at the beginning and during step a) to the circulation device (21) by actuating the control device having the computer program product, which device is connected to the shut-off member (24) using information technology, wherein the connection device (23) acts as an inlet, and the at least one shut-off member (24), by actuating the control device, fluidically separates the connection device (23) during step b) and at the end of step a) from the circulation device (21), wherein the connection device (23) acts as a drain.
9. Method according to claim 8, characterised in that method steps a) and/or b) and/or c) are repeated as often as desired.
10. Method according to either claim 8 or claim 9, further comprising a rinse agent cleaning step, in which a rinse agent is conveyed out of the third supply device through the rinse agent conveying unit (14) via the distribution device (16) into the circulation circuit and, together with water as a water-rinse agent mixture, is conveyed through the connection device (23) into the cooking chamber (3) until a characteristic fill level is reached, at which level the circulation device (21) is activated and the water-rinse agent mixture is conveyed out of the connection device (23) via the connection elements (17, 18, 19, 20) of the circulation circuit through the return pipe (22) to the ventilation device (29) of the cooking chamber (3), where the water-rinse agent mixture is distributed in the cooking chamber (3) and, after cleaning, the used water-rinse agent mixture flows through the connection device (23) into the drain.
11. Method according to any of claims 8 to 10, characterised in that the computer program product of the control device comprises commands which cause at least steps a) to c) to be carried out.
12. Use of a cleaning system (1) according to any of claims 1 to 6 or a method according to any of claims 8 to 11 for cleaning the cooking chamber (3) of a cooking appliance (2) as defined in claim 7.
13. Use of a computer program product or a control device on which the computer program product is stored for carrying out a method according to any of claims 8 to 11, wherein the computer program product comprises commands which cause at least steps a) to c) to be carried out.

Images