Cassette and apparatus for liquid freezing

Abstract

A cassette for use in freezing a liquid contained in a plurality of liquid receptacles comprises a bottom plate for supporting a number of the liquid receptacles in a layer, a number of intermediate plates having essentially the same dimensions as the bottom plate for placing on a layer of the liquid receptacles and supporting a further layer of liquid receptacles, and two opposite side walls being rigidly connected to the bottom plate for constituting a U-form therewith, so that each intermediate plate when placed on a layer of the liquid receptacles will be fixed laterally in relation to the side walls. A freezer for freezing of a liquid contained in a plurality of liquid receptacles comprises a freezing tunnel, the cassette, and a cassette holder having a stand, for supporting the cassette and a number of the intermediate plates separated form the cassette, the cassette holder being mobile for movement from a station for loading of the cassette with the liquid receptacles and the intermediate plates to the freezing tunnel for inserting the loaded cassette therein.

1 . A cassette for use in freezing a liquid contained in a plurality of liquid receptacles ( 25 ), said freezing comprising inserting the cassette ( 6 ) with the liquid receptacles ( 25 ) into a freezing tunnel ( 5 ) having a streaming cooling medium and keeping them therein until the liquid in all the liquid receptacles ( 25 ) in the cassette ( 6 ) is frozen, 
 comprising:    a bottom plate ( 12 ) for supporting a number of the liquid receptacles ( 25 ) in a layer,    a number of intermediate plates ( 15 ) having essentially the same dimensions as the bottom plate ( 12 ) for placing on a layer of liquid receptacles ( 25 ) and supporting a further layer of liquid receptacles ( 25 ), and    two opposite side walls ( 13 ,  14 ) being rigidly connected to the bottom plate ( 12 ) for constituting a U-form therewith, so that each intermediate plate ( 15 ) when placed on a layer of liquid receptacles ( 25 ) will be fixed laterally in relation to the side walls ( 13 ,  14 ).    
     
     
         2 . A cassette as claimed in  claim 1 , wherein each intermediate plate ( 15 ) has means ( 16 ) cooperating with the side walls ( 13 ,  14 ) so that each intermediate plate ( 15 ) when placed on a layer of liquid receptacles ( 25 ) will be fixed lengthwise in relation to the side walls ( 13 ,  14 ).  
     
     
         3 . A cassette as claimed in  claim 2 , wherein the liquid receptacles ( 25 ) are flexible and each intermediate plate ( 15 ) has spacer means ( 16 ,  26 ) determining the distance to the subjacent intermediate plate ( 15 ) and the bottom plate ( 15 ), respectively.  
     
     
         4 . A cassette as claimed in  claim 1 , wherein each intermediate plate ( 15 ) and the bottom plate ( 12 ) have a number of full length ducts extending in the plane of the plate for admitting the streaming of the cooling medium through them and thereby a cooling of the bottom plate ( 12 ) and the intermediate plates ( 15 ), when the cassette ( 6 ) is inserted in the freezing tunnel ( 5 ).  
     
     
         5 . A freezer for freezing a liquid contained in a plurality of liquid receptacles ( 25 ) said freezer comprising a cassette ( 6 ) for supporting the liquid receptacles ( 25 ) and a freezing tunnel ( 5 ) for a streaming cooling medium, the cassette ( 6 ) with the liquid receptacles ( 25 ) being insertable into the freezing tunnel ( 5 ) and kept therein until the liquid in all the liquid receptacles ( 25 ) in the cassette ( 6 ) is frozen, 
 wherein the cassette ( 6 ) comprises a bottom plate ( 12 ) for supporting a number of liquid receptacles ( 25 ) in a layer and a number of intermediate plates ( 15 ) having substantially the same dimensions as the bottom plate ( 12 ) for being placed each on a separate layer of liquid receptacles ( 25 ) and each supporting a further layer of liquid receptacles ( 25 ),    a cassette holder ( 11 ;  30 ) is provided having a frame ( 23 ) for supporting the cassette ( 6 ) and a number of intermediate plates ( 15 ) separated from the cassette ( 6 ), and    the cassette holder ( 11 ;  30 ) is mobile for movement from a station for loading of the cassette ( 6 ) with the liquid receptacles ( 25 ) and the intermediate plates ( 15 ) to the freezing tunnel ( 5 ) for inserting the loaded cassette ( 6 ) therein.    
     
     
         6 . A freezer as claimed in  claim 5 , wherein the cassette holder ( 11 ;  30 ) has a stand ( 20 - 22 ;  32 ) for placing the intermediate plates ( 15 ) in a sloping or substantially vertical position in contact with each other and successively displaced in height.  
     
     
         7 . A freezer as claimed in  claim 6 , wherein the frame ( 23 ) of the cassette holder ( 11 ) is equipped with wheels ( 24 ).  
     
     
         8 . A freezer as claimed in  claim 5 , further comprising lifting equipment ( 31 ) for raising and lowering the cassette ( 6 ) on the cassette holder ( 30 ) such that the intermediate plates ( 15 ) may be loaded and unloaded at substantially the same height.  
     
     
         9 . A freezer as claimed in  claim 5 , wherein the cooling medium of the freezing tunnel ( 5 ) is air.  
     
     
         10 . A freezer as claimed in  claim 6 , wherein the stand for placing the intermediate plates ( 15 ) is releasable from the frame of the cassette holder.  
     
     
         11 . A cassette as claimed in  claim 2 , wherein each intermediate plate ( 15 ) and the bottom plate ( 12 ) have a number of full length ducts extending in the plane of the plate for admitting the streaming of the cooling medium through them and thereby a cooling of the bottom plate ( 12 ) and the intermediate plates ( 15 ), when the cassette ( 6 ) is inserted in the freezing tunnel ( 5 ).  
     
     
         12 . A cassette as claimed in  claim 3 , wherein each intermediate plate ( 15 ) and the bottom plate ( 12 ) have a number of full length ducts extending in the plane of the plate for admitting the streaming of the cooling medium through them and thereby a cooling of the bottom plate ( 12 ) and the intermediate plates ( 15 ), when the cassette ( 6 ) is inserted in the freezing tunnel ( 5 ).