Patent Publication Number: US-8981262-B2

Title: Steamer device

Description:
BACKGROUND OF THE INVENTION 
     The invention is based on a steam cooking appliance apparatus. 
     A steam cooking appliance apparatus having a muffle unit bounding a cooking chamber is known from the publication DE 28 42 771 C2. The steam cooking appliance apparatus has a cleaning unit, by means of which a fluid cleaning agent can be introduced into the cooking chamber. 
     A cooking appliance having a cleaning apparatus is known from the publication DE 199 61 835 C2. During a cleaning process the cleaning apparatus introduces fluid into a cooking chamber of the cooking appliance. 
     BRIEF SUMMARY OF THE INVENTION 
     The object of the invention is in particular to provide a generic apparatus with improved attributes in respect of simple cleanability. According to the invention the object is achieved by the features of claim  15 , while advantageous embodiments and developments of the invention will emerge from the subclaims and the independent claim. 
     The invention is based on a steam cooking appliance apparatus having a muffle unit at least partially bounding a cooking chamber, featuring a muffle element forming a cooking chamber boundary surface in at least one operating state, and having at least one cleaning unit, which is provided to clean at least part of the muffle unit. 
     It is proposed that the cooking chamber boundary surface has a lower cooking fat adhesion than stainless steel. A “cleaning unit” here refers in particular to a unit which in at least one operating state is functionally connected to at least one further component of the steam cooking appliance apparatus and is preferably fastened to this and which is provided to clean at least one component of the steam cooking appliance apparatus. A “muffle element forming a cooking chamber boundary surface” here refers in particular to an element, which in at least one cooking process taking place in a cooking chamber forms a surface, which directly bounds the cooking chamber. The statement that the cooking chamber boundary surface has a “lower cooking fat adhesion than stainless steel” is intended in particular to mean that a deposit on the cooking chamber boundary surface deposited on the cooking chamber boundary surface during a heating process to heat an item to be cooked in the cooking chamber in the course of an overall heating time of the heating process can be detached with less force from the cooking chamber boundary surface than a deposit deposited on the cooking chamber boundary surface during the same heating process, if said surface were made of stainless steel. The item to be cooked here is formed in particular at least partially from animal and/or vegetable material, in particular from animal and/or vegetable fats and in particular from olive oil, which consists in particular of fatty acids bound to glycerine, 72 percent of the fatty acids being formed by oleic acid, 8 percent by linoleic acid, 12 percent by palmitic acid, 3 percent by stearic acid and 5 percent by palmitoleic acid. A “heating process to heat an item to be cooked” refers in particular to a process, in which the item to be cooked is heated at least partially to over 140° C. and preferably to over 180° C. and is preferably heated to said temperatures for at least fifty percent of the overall heating time of the heating process. An “overall heating time of the heating process” refers in particular to a time during which, in the performance of the heating process, heat generated by at least one heating element is supplied to the item to be cooked, the time preferably being ten minutes and even more preferably one hour. The fact that the first-mentioned deposit can be detached with “less force” than the second-mentioned deposit means in particular that when using the same tool, preferably a spatula, to detach the deposits, for a complete removal in each instance of every part of the deposits with a single hand movement in each instance, a smaller maximum force is required to detach the first-mentioned deposit than to detach the second-mentioned deposit. “Stainless steel” refers in particular to a stainless steel with the material number 1.4404 or 1.4301. Simple cleanability can be achieved with an inventive embodiment. In particular it is possible to detach deposits from the cooking chamber boundary surface with little force expenditure and in particular by means of an at least partially automated cleaning process, which can include in particular the spraying of water and/or cleaning fluid onto the cooking chamber boundary surface. 
     It is also proposed that at least part of the muffle unit is configured with two layers at least. The fact that a part of the muffle unit is “configured with two layers” means in particular that the part has at least two layers that rest at least partially against one another and—in at least a front view, looking at one of the layers at least—at least partially one on top of the other. This allows an economical construction to be achieved. In particular it is possible for the cooking chamber boundary surface to be formed economically by a coating. 
     The muffle element is preferably formed at least partially from a polymer and/or enamel and/or silicon. The muffle element is preferably formed at least partially from polytetrafluoroethylene. In particular the muffle element is formed at least partially from the plastic known as Teflon, which is largely formed from the material polytetrafluoroethylene. This allows a particularly low cooking fat adhesion to be achieved. It is possible in particular to prevent the muffle rusting. 
     The steam cooking appliance apparatus advantageously has at least one application unit, which is provided to apply the muffle element in a free-flowing state to at least part of the muffle unit. “Provided” here means in particular specifically designed and/or specifically equipped. A substance in a “free-flowing” state refers in particular to a substance in a state which has sub-regions that move relative to one another when the substance is distributed. An “application” of the muffle element to part of the muffle unit refers in particular to the bringing into contact of the muffle element with the part and subsequent fastening and/or adhesion of the muffle element to the part. This allows particularly thorough cleanability to be achieved. In particular it is possible for dirt adhering to the muffle element to be removed together with the muffle element in a simple manner after a cooking process. The muffle element is preferably formed at least partially by a powder, allowing the muffle element to be detached easily. The muffle element is advantageously formed by at least one substance, which is fluid in the free-flowing state, thereby allowing it to be applied particularly easily. 
     The steam cooking appliance apparatus preferably has at least one substance introduction unit, which is provided to introduce at least one substance into the cooking chamber. This allows user-friendly cleanability to be achieved. In particular a muffle unit can be cleaned with the aid of a jet of fluid and/or steam. 
     It is also proposed that the substance introduction unit has at least one line opening into the cooking chamber. A “line” refers in particular to an element provided to convey fluids and/or gases from an initial region of the element through a hollow space in the element to a final region of the element, with the length of a path traveled by a substance conveyed by the element deviating by less than eighty percent, preferably by less than forty percent and particularly preferably by less than ten percent from a maximum lengthways extension of the element. This allows flexible introduction of a substance into the cooking chamber. In particular with a simple construction a substance can be introduced into the cooking chamber through openings disposed on a number of sides of the cooking chamber. 
     The steam cooking appliance apparatus preferably has at least one arm unit, which features at least part of the line and through which the substance introduction unit introduces steam into the cooking chamber in at least one operating process. An “arm unit” refers in particular to a unit, which features at least one arm, which has a maximum lengthways extension, which is at least three times, preferably at least five times and particularly preferably at least ten times as long as a maximum widthways extension and a maximum height extension of the unit. This allows efficient introduction of the steam and in particular even distribution of the steam in the cooking chamber to be achieved. 
     The muffle unit advantageously features at least one accessory holding region, which is separate from the cooking chamber and which is provided at least partially to hold at least one cleaning unit provided for removal by a user and/or at least one coating unit and/or at least one fluid introduction unit. An “accessory holding region” refers in particular to a holding region provided to be free of items to be cooked in any operating state and in particular during any operational cooking process. A “coating unit” refers in particular to a unit, by means of which a surface, in particular of a cooking chamber, can be coated. This allows a user-friendly construction to be achieved. 
     It is also proposed that the steam cooking appliance apparatus should feature at least one care agent connector, which is provided to introduce care agent from a care agent supply that is independent of the appliance. A “care agent supply that is independent of the appliance” refers in particular to a line unit for transporting care agent which is configured as separate from the steam cooking appliance apparatus and preferably separate from a household appliance that features the steam cooking appliance apparatus. A “care agent” refers in particular to a substance for caring for and preferably cleaning surfaces. This ensures that it is convenient to use. 
     A steam cooking appliance apparatus having at least one cooking steam introduction unit and at least one cleaning steam introduction unit, which is configured in part at least as separate from the cooking steam introduction unit, is also proposed. The fact that the cleaning steam introduction unit is configured “in part at least as separate” from the cooking steam introduction unit means in particular that the cooking steam introduction unit is free of at least one steam supply line, which is part of the cleaning steam introduction unit. A “cooking steam introduction unit” refers in particular to a steam introduction unit, which is mainly provided to introduce steam for cooking purposes. A “cleaning steam introduction unit” refers in particular to a steam introduction unit, which is mainly provided to introduce steam for cleaning a cooking chamber boundary surface and which preferably sprays steam directly onto the cooking chamber boundary surface when it is introduced into the cooking chamber. This allows simple cleanability to be achieved. 
     A household appliance having a steam cooking appliance apparatus with which simple cleanability can be achieved is also proposed. 
     A steam cooking appliance cleaning method, in particular for cleaning the steam cooking appliance apparatus, is also proposed, in which a fluid is injected and/or sprayed onto at least one cooking chamber boundary surface, which has a lower cooking fat adhesion than stainless steel. This allows simple cleanability to be achieved. 
     A muffle element is preferably applied to at least one muffle component before the fluid is injected and/or sprayed on. This allows particularly thorough cleanability to be achieved. In particular it is possible for dirt adhering to the muffle element to be removed together with the muffle element in a simple manner after a cooking process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages will emerge from the description of the drawings which follows. The drawing shows exemplary embodiments of the invention. The drawing, description and claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them in useful further combinations. 
         FIG. 1  shows a front view of a household appliance configured as a steam oven with an inventive steam cooking appliance apparatus, 
         FIG. 2  shows a section through a muffle unit of the steam cooking appliance apparatus, 
         FIG. 3  shows part of a section through an arm unit of the steam cooking appliance apparatus, 
         FIG. 4  shows part of a front view of the steam cooking appliance apparatus, with a door of the steam cooking appliance open and the arm unit in a stowed state, and 
         FIG. 5  shows an alternative exemplary embodiment of a steam cooking appliance apparatus. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION 
       FIG. 1  shows a steam oven having a household appliance apparatus, which is configured as an inventive steam cooking appliance apparatus. The steam cooking appliance apparatus features a muffle unit  12 , which comprises a muffle element  16 . The muffle unit  12  forms a useful space  10  of the steam cooking appliance apparatus configured as a cooking chamber  10 ′, with the muffle element  16  forming a cooking chamber boundary surface  14 , which directly bounds the cooking chamber  10 ′. The steam cooking appliance apparatus further features a cleaning unit  18 , which is provided to clean the cooking chamber boundary surface  14  and an inner surface of a door  50  of the steam cooking appliance apparatus, which directly bounds the cooking chamber  10 ′ when the door  50  is closed. 
     The muffle element  16  is configured as a Teflon layer  52  ( FIG. 2 ), with the result that the cooking chamber boundary surface  14  has lower cooking fat adhesion than stainless steel. The Teflon layer  52  is disposed on a layer  54  of the muffle unit  12  formed from stainless steel. 
     A substance supply unit  44  of the steam cooking appliance apparatus features the cleaning unit  18 , which likewise forms a substance introduction unit  24  for introducing substances into the cooking chamber  10 ′. The substance introduction unit  24  is formed by an arm unit  28 , which is supported rotatably by a bearing unit  58  and features the line  26  configured as a fluid line  26 ′, which opens at opening points  56  into the cooking chamber  10 ′ ( FIGS. 1 and 3 ). The opening points  56  can in principle also be formed by nozzles. During operating processes the substance introduction unit  24  conducts steam and/or fluid, which in particular comprises a cleaning agent, in particular featuring rinse aids and/or tensides, through the line  26  and the opening points  56  into the cooking chamber  10 ′. The steam and fluid can be introduced into the cooking chamber  10 ′ at a high pressure. The introduction of the steam is initiated by a steam supply unit  46  of the substance supply unit  44 , of which the substance introduction unit  24  is a part. Because the arm unit  28  only features opening points  56  in one side region  66  respectively on each of the two arm segments  62 ,  64  and the arm unit  28  is supported rotatably about an axis  60  running vertically in an operating state, the arm unit  28  rotates about the axis  60  when the fluid or steam exits into the cooking chamber  10 ′. This means that an entire cooking chamber boundary surface  14  is sprayed evenly with the fluid or steam. Spraying with the fluid detaches food residues present on the Teflon layer  52 , these being formed predominantly by fat. The steam supply unit  46  forms a cleaning steam introduction unit  40  of the steam cooking appliance apparatus. Cleaning by means of the steam supply unit  46  preferably takes place in that before spraying with the fluid, steam is introduced through the arm unit  28  into the cooking chamber  10 ′, thereby softening the food residues and making them easy to detach from the Teflon layer  52 . When the Teflon layer  52  has been cleaned, it can be dried by a standard heating system  72  of the steam cooking appliance apparatus. The standard heating system  72  is configured as a circulating heater. The standard heating system  72  also allows cooking processes to be operated in the cooking chamber  10 ′, in which there is no need for steam. 
     In addition to the cleaning steam introduction unit  40  the steam cooking appliance apparatus also features a cooking steam introduction unit  38  ( FIG. 1 ), which introduces steam into the cooking chamber  10 ′ in such a manner that its inflow direction is directed towards a center point of the cooking chamber  10 ′, with the result that items to be cooked come into contact with the steam shortly after the steam has entered the cooking chamber  10 ′. 
     The substance introduction unit  44  also features a care agent connector  36 , which is disposed on a rear face of the household appliance and which is connected to a line configured as separate from the household appliance when the household appliance is fitted, said line being provided to convey care agent through the care agent connector  36  into the household appliance. 
     The muffle unit  12  also features an accessory holding region  48 , in which the arm unit  28  is held in its entirety in at least one operating state of the household appliance apparatus ( FIG. 4 ). The accessory holding region  48  is formed by a depression  48 ′ in a muffle flange  68  of the muffle unit  12 . The depression  48 ′ extends from a surface of the muffle flange  68 , against which a sealing unit (not shown) of the household appliance apparatus rests when the door  50  is closed, in a depthways extension direction of the cooking chamber  10 ′. The muffle unit  12  also features a fastening means (not shown), to which the arm unit  28  can be fastened without tools. 
     Water can be supplied to the substance supply unit  44  through a connector to a water network or water tank, with the substance supply unit  44  in the second instance featuring a pump to produce a high pressure. The steam cooking appliance apparatus also features a collection system (not shown) to collect fluids. 
       FIG. 5  shows an alternative exemplary embodiment. Essentially identical components, features and functions are basically shown with the same reference characters. To differentiate between the exemplary embodiments however the letter “a” is appended to the reference character of the exemplary embodiment in  FIG. 5 . The description which follows is essentially limited to the differences in relation to the exemplary embodiment in  FIGS. 1 to 4 , it being possible to refer to the description of the exemplary embodiment in  FIGS. 1 to 4  in respect of identical components, features and functions. 
       FIG. 5  shows an alternative exemplary embodiment of a steam cooking appliance apparatus having a substance introduction unit  24   a , which is fastened to a muffle unit  12   a  of the steam cooking appliance apparatus and which is formed by nozzles  24 ′ a . In an operational state a muffle component  42   a  made of stainless steel directly bounds a cooking chamber  10 ′ a  of the steam cooking appliance apparatus. In preparation for a cooking process silicon can be applied to the muffle component  42   a  by means of the substance introduction unit  24   a , so that the silicon forms a muffle element  16   a  of the muffle unit  12   a , forming a cooking chamber boundary surface  14   a . After a cooking process a fluid is injected into the cooking chamber  10 ′ by means of the substance introduction unit  24   a , washing the silicon from the muffle component. In a certain operating mode the muffle element  16   a , which is introduced into the cooking chamber by the substance introduction unit  24   a , can also be formed by powder. An entire surface of the steam cooking appliance apparatus, which bounds the cooking chamber  10 ′ a , can be flushed with the aid of the substance introduction unit  24   a . 
     
       
         
           
               
             
               
                   
               
               
                 Reference characters 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                 10 
                 Useful space 
               
               
                   
                 10′ 
                 Cooking chamber 
               
               
                   
                 12 
                 Muffle unit 
               
               
                   
                 14 
                 Cooking chamber boundary surface 
               
               
                   
                 16 
                 Muffle element 
               
               
                   
                 18 
                 Cleaning unit 
               
               
                   
                 20 
                 Application unit 
               
               
                   
                 24 
                 Substance introduction unit 
               
               
                   
                 24′ 
                 Nozzle 
               
               
                   
                 26 
                 Line 
               
               
                   
                 26′ 
                 Fluid line 
               
               
                   
                 28 
                 Arm unit 
               
               
                   
                 36 
                 Care agent connector 
               
               
                   
                 38 
                 Cooking steam introduction unit 
               
               
                   
                 40 
                 Cleaning steam introduction unit 
               
               
                   
                 42 
                 Muffle component  
               
               
                   
                 44 
                 Substance supply unit 
               
               
                   
                 46 
                 Steam supply unit 
               
               
                   
                 48 
                 Accessory holding region 
               
               
                   
                 48′ 
                 Depression 
               
               
                   
                 50 
                 Door 
               
               
                   
                 52 
                 Teflon layer 
               
               
                   
                 54 
                 Layer 
               
               
                   
                 56 
                 Opening point 
               
               
                   
                 58 
                 Bearing unit 
               
               
                   
                 60 
                 Axis 
               
               
                   
                 62 
                 Arm segment 
               
               
                   
                 64 
                 Arm segment 
               
               
                   
                 66 
                 Side region 
               
               
                   
                 68 
                 Muffle flange 
               
               
                   
                 70 
                 Depthways extension direction 
               
               
                   
                 72 
                 Standard heating system