Ice making assembly for a refrigerator appliance

A refrigerator appliance defining a vertical direction, a lateral direction, and a transverse direction, comprising:

• a cabinet defining a chilled chamber;
• a door being rotatably mounted to the cabinet to provide selective access to the chilled chamber;
• an icebox mounted to the door and defining an ice making chamber;
• an ice making assembly positioned within the ice making chamber, the ice making assembly comprising:
• a resilient mold defining a mold cavity;
• a fill cup positioned above the resilient mold for selectively filling the mold cavity with water;
• a heat exchanger in thermal communication with the resilient mold to freeze the water and form one or more ice cubes;
• a lifter mechanism positioned below the resilient mold and being movable between a lowered position and a raised position to deform the resilient mold and raise the one or more ice cubes;
• and
• a resilient seal comprising a cylindrical portion, a bottom portion generally perpendicular to the cylindrical portion, and a shoulder defining a joint and transition between the cylindrical portion and the bottom portion, the resilient seal sealingly engaged with the lifter mechanism, whereby an air-tight seal is formed between the lifter mechanism and the resilient seal and between the heat exchanger and the resilient seal, the cylindrical portion of the resilient seal received within a recess in the heat exchanger,
• wherein the resilient mold is sealingly engaged with the heat exchanger, whereby an air-tight seal is formed between the resilient mold and the heat exchanger,
• wherein a hermetically sealed cavity is defined by and formed between the resilient mold, the heat exchanger, the lifter mechanism, and the resilient seal,
• wherein the cylindrical portion of the resilient seal moves with the lifter mechanism and the cylindrical portion of the resilient seal flexes and compresses as the lifter mechanism moves between the lowered position and the raised position, whereby the air-tight seal between the resilient seal and the lifter mechanism and the hermetically sealed cavity are maintained as the lifter mechanism moves between the lowered position and the raised position,
• wherein the hermetically sealed cavity defines a generally fixed volume, whereby a discrete quantity of air is contained within the hermetically sealed cavity, whereby moisture intrusion into the hermetically sealed cavity and resultant frosting of the underside of the resilient mold is impeded.