Patent ID: 8157360

Claim:
A valve device which opens and closes a passage at least a part of which is defined by a film material, the device comprising: a valve seat provided in the passage; a valve member provided in the passage, wherein the valve member is movable in directions of approaching and separating from the valve seat so as to close and open the passage; and an avoidance mechanism which is provided in the passage, wherein the avoidance mechanism restricts movement of the valve member so as to prevent the valve member from contacting the film material, wherein the avoidance mechanism includes a guide member which is provided in the passage so as to guide movement of the valve member, and an abutting portion which is provided in the valve member so as to be able to abut on the guide member, and the movement of the valve member in the direction toward the film material is restricted by the abutting portion abutting on the guide member; and ac actuating member moveable between a first position and a second position relative to the passage, wherein the actuating member has a magnet, the valve member comprises a magnetic body, wherein the actuating member is located in the first position, and attraction that can move the valve member acts between the magnet and the magnetic body, and, when the actuating member is located in the second position, the attraction that can move the valve member does not act between the magnet and the magnetic body, and, when the actuating member is located in the first position, the film material is located between the magnet and the valve member.