Membrane for closing containers in general, and a product preservation device comprising said membrane

Abstract

The membrane ( 1 ) for closing containers in general comprise a body ( 2 ) of elastic material defining a portion ( 3 ) for its retention on said container ( 4 ) and a portion ( 5 ) for closing this latter. The membrane comprises an unidirectional valve ( 6 ) co-moulded with the body ( 2 ) for discharging the air contained in the container ( 4 ) to the outside. The food product preservation device comprises a container ( 4 ) to receive the food products ( 26 ) and a lid ( 27 ) for their protection. The device also comprises the membrane ( 1 ) interposable between the container ( 4 ) and the lid ( 27 ).

1 . A membrane ( 1 ) for closing containers in general, comprising a body ( 2 ) of elastic material defining a portion ( 3 ) for its retention on said container ( 4 ) and a portion ( 5 ) for closing this latter, the membrane comprising valving means ( 6 ) comprising a unidirectional valve co-moulded with said body ( 2 ) for discharging the air contained in said container ( 4 ) to the outside.  
   
   
       2 . A membrane ( 1 ) as claimed in  claim 1 , characterised in that said valve ( 6 ) is positioned on the closure portion ( 5 ) of the membrane ( 1 ), at the union border ( 5   a ) between the same closure portion ( 5 ) and the retention portion ( 3 ).  
   
   
       3 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said valve ( 6 ) presents at least one thickened portion ( 13 ) presenting a conduit ( 14 ) which defines said inner port ( 11 ), and an end portion ( 15 ) presenting a slit ( 16 ) extending between an end ( 17 ) of said conduit ( 14 ) and the outside ( 18 ), said slit ( 16 ) being openable by the effect of mechanical stresses, to enable air to pass.  
   
   
       4 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said unidirectional valve is connectable to suction means.  
   
   
       5 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said valve ( 6 ) is at least partially connected to said retention portion ( 3 ) of said body ( 2 ).  
   
   
       6 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said body ( 2 ) presents a connection channel ( 7 ) between said valve ( 6 ) and the interior ( 8 ) of said container ( 4 ).  
   
   
       7 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said channel ( 7 ) is defined by ribs ( 9 ) which extend to the side of an inner port ( 11 ) of said valve ( 6 ) along an inner surface ( 12 ) of said retention portion ( 3 ).  
   
   
       8 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said slit ( 16 ) is realised by a blade, to guarantee the perfect sealing of the valve.  
   
   
       9 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said closure portion ( 5 ) presents a substantially convex profile.  
   
   
       10 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said closure portion ( 5 ) presents a plurality of undulations ( 21 ) substantially parallel to the perimeter of said closure portion ( 5 ).  
   
   
       11 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said closure portion ( 5 ) is substantially circular, said undulations ( 21 ) also being circular and concentric.  
   
   
       12 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said retention portion ( 3 ) presents at least one perimetral rib ( 22 ) which extends along its outer surface.  
   
   
       13 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that a central zone of the closure portion ( 5 ) has a strengthening ( 5   b ).  
   
   
       14 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that said strengthening ( 5   b ) is made up a more thickness of the membrane.  
   
   
       15 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised by being applicable to a container by pushing the sides of the valve to open it and to keep it in open configuration and, at the same time, pushing the closure portion ( 5 ) of the membrane.  
   
   
       16 . A membrane ( 1 ) as claimed in one or more of the preceding claims, characterised in that, when it is applied, the vapour developing in the container to which it is applied during the warming and the air which during warming increases its volume are discharged through the valve ( 6 ).  
   
   
       17 . A food product preservation device comprising a container ( 4 ) to receive said food products ( 26 ) and a lid ( 27 ) for their protection, characterised by comprising, interposable between said container ( 4 ) and said lid ( 27 ), a membrane ( 1 ) comprising a body ( 2 ) of elastic material defining a portion ( 3 ) for its retention on said container ( 4 ) and a portion ( 5 ) for closing this latter, said membrane ( 1 ) comprising at least one valve ( 6 ) for discharging the air contained in said container ( 4 ) to the outside.  
   
   
       18 . A device as claimed in the preceding claim, characterised in that said lid ( 27 ) presents a first seat ( 28 ) for the passage of said valve ( 6 ).  
   
   
       19 . A device as claimed in  claim 17  or  18 , characterised in that said lid ( 27 ) presents a second seat ( 29 ) enabling said containers ( 4 ) to be stacked one on another.  
   
   
       20 . A device as claimed in one or more of claims  17  and onwards, characterised in that said unidirectional valve is associable with suction means ( 25 ).  
   
   
       21 . A device as claimed in one or more of claims  17  and onwards, characterised in that said container ( 4 ) presents a substantially horizontal perimetral free edge ( 30 ) on which said membrane can grip, said retention portion ( 3 ) of said membrane ( 1 ) presenting at least one horizontal part ( 31 ) which rests against said horizontal edge ( 30 ) of said container ( 4 ) and a substantially U-bent part ( 32 ) which locks said membrane ( 1 ) onto said container ( 4 ).  
   
   
       22 . A device as claimed in one or more of claims  17  and onwards, characterised by comprising a separation grid ( 40 ) interposable between said food products ( 26 ) and said membrane ( 1 ).  
   
   
       23 . A device as claimed in one or more of claims  17  and onwards, to characterised in that said grid ( 40 ) presents, for separating said food product ( 26 ) from said membrane ( 1 ), a surface ( 41 ) from which legs ( 42 ) extend.  
   
   
       24 . A device as claimed in one or more of claims  17  and onwards, characterised in that said surface ( 41 ) presents a free edge ( 43 ) which is inserted as an exact fit into the container ( 4 ) so as to completely separate the food product ( 26 ) from the membrane and prevent the existence of regions where direct contact can occur.