Patent ID: 8485771

Claim:
A load port apparatus that attaches/detaches a lid of a pod composed of said lid and a body portion that has an opening to be closed by said lid on one side and stores a content object in the interior, thereby opening/closing said opening to allow transfer of said content object into and out of said body portion, comprising: a wall that defines a mini-environment on a first side thereof and an external space on a second side thereof and has an opening portion that allows communication between said mini-environment and said external space; a door that is disposed on said first side of said wall, closes said opening portion, and can hold said lid; a support table that supports said pod at such a position that allows said opening to be opposed to said opening portion on said second side of the wall; a door driving mechanism that supports said door on said first side by a door supporting portion that operates on said second side to support said door and moves said door between a closing position at which the door closes said opening portion and an opening position at which the door leaves said opening portion; a housing chamber disposed on said second side and houses said door driving mechanism, and defined as a chamber by plate members including a front wall and a bottom wall; and a communication opening portion provided in said wall through which said door supporting portion can pass and that allows communication between said housing chamber and said mini-environment, wherein said housing chamber has a first exhaust opening portion and a second exhaust opening portion, said first exhaust opening portion being provided in said front wall of said plate members of said housing chamber, opposed to said communication opening portion, so as to allow communication between said housing chamber and said external space, said second exhaust opening portion being provided in said bottom wall of said plate member of said housing chamber, and located at a position to which said door driving mechanism comes closest in the state in which said door leaves said opening portion open, so as to allow communication between said housing chamber and said external space, and wherein a pressure difference is produced between spaces in said mini-environment and in said housing chamber, and there is produced a pressure difference between the space in said housing chamber and said external space, in such a way that pressure in said mini-environment, said housing chamber, and said external space decreases in order of the mini-environment that contains said door on said first side, said housing chamber, and said external space, and streams of gas from said housing chamber to said external space through said first exhaust opening portion and said second exhaust opening portion are created by said pressure differences.