Windowed door for a cooking appliance

Abstract

The present invention relates to a windowed door ( 4 ) for a cooking appliance ( 2 ), in particular a cooking oven. The windowed door ( 4 ) comprises a front plate ( 6 ) and at least one inner plate ( 22 ) facing a cooking chamber ( 30 ) of the cooking appliance ( 2 ), wherein the front plate ( 6 ) and the at least one inner plate ( 22 ) each provide a glass pane ( 8, 24 ) and are connected with each other by at least lateral frame parts ( 26 ) to establish an air channel ( 11 ) from at least one air inlet opening ( 13 ) arranged at the bottom of the door ( 4 ) through a hollow space ( 28 ) between the glass pane ( 8 ) of the front plate ( 6 ) and the glass pane ( 24 ) of the at least one inner plate ( 22 ) to at least one air outlet opening ( 14 ) arranged at the top of the door ( 4 ). To regulate the air flow through the air channel ( 11 ) at least one automatically moveable closure device ( 40 ) is provided which permits the regulation of the air flow by changing the cross-section of at least one air passage aperture ( 29 ) within ( 64 ) or at the end ( 62 ) or at the beginning ( 60 ) of the air channel ( 11 ).

1 . Windowed door for a cooking appliance comprising a front plate and at least one inner plate facing a cooking chamber of the cooking appliance, wherein the front plate and the at least one inner plate each provide a glass pane and are connected with each other by at least lateral frame parts to establish an air channel from at least one air inlet opening arranged at the bottom or in at least one lateral side of the door through a hollow space between the glass pane of the front plate and the glass pane of the at least one inner plate to at least one air outlet opening arranged at the top of the door and wherein at least one automatically moveable closure device is provided which permits the regulation of air flow through the air channel by changing the cross-section of at least one air passage aperture within or at the end or at the beginning of the air channel. 
     
     
         2 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device is designed so that it can completely interrupt an air flow through the hollow space. 
     
     
         3 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device is arranged within a door cap which is arranged at the top of the windowed door. 
     
     
         4 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device is arranged between the front plate and the at least one inner plate. 
     
     
         5 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device is in direct contact with front plate or the at least one inner plate when interrupting the air flow through the hollow space. 
     
     
         6 . Windowed door according to  claim 1 , wherein between the front plate and the at least one inner plate at least one further plate comprising a glass pane is arranged. 
     
     
         7 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device is designed to carry out a horizontal movement to regulate the air flow through the hollow space. 
     
     
         8 . Windowed door according to  claim 1 , wherein the at least one automatically moveable closure device comprises at least one shape memory alloy element designed to change the cross-section of the at least one air passage aperture by moving of a cover element. 
     
     
         9 . Windowed door according to  claim 8 , wherein the shape memory alloy element is designed to cause a movement of the cover element at a predefined temperature. 
     
     
         10 . Windowed door according to  claim 8 , wherein the shape memory alloy element is designed to cause a progressive movement of the cover element dependent on the temperature change of air within the air channel. 
     
     
         11 . Windowed door according to  claim 8 , wherein the at least one automatically moveable closure device comprises at least one return member designed to bring back the shape memory alloy element into an initial shape after a warming up process followed by a cooling down process of the shape memory alloy element. 
     
     
         12 . Windowed door according to  claim 8 , wherein the a shape modification of the shape memory alloy element is caused by heating of the shape memory alloy element via radiation heat emanating of the cooking chamber of the cooking appliance or via Joule heating or via induction heating. 
     
     
         13 . Windowed door according to  claim 8 , wherein the cover element is essentially made from metal or plastic. 
     
     
         14 . Cooking appliance comprising a windowed door according to  claim 1 . 
     
     
         15 . Cooking appliance according to  claim 14 , wherein the cooking appliance provides
 a) a first and a second channel which are placed one above the other and wherein the first channel is arranged above the housing of a cooking chamber and the second channel is arranged beyond a control unit of the cooking appliance, and   b) a cooling fan arranged at an area where the first and second channel are in operative connection with each other to provide an air flow of air entering into the at least one air inlet opening, passing through the hollow space and then escaping via the at least one air outlet opening, the first channel and the second channel.   
     
     
         16 . Windowed door according to  claim 9 , said predefined temperature being within a temperature range of 40° C. to 100° C.