Patent ID: 8354636

Claim:
A mass spectrometer comprising an ionization chamber for ionizing a specimen and a mass spectrometer unit to which ions from said ionization chamber are introduced, wherein said ionization chamber comprises: an enclosure comprising a first wall surface, a second wall surface and a third wall surface, said enclosure forming an internal space; a probe installed on said first wall surface for spraying specimen into said ionization chamber; and a tube formed on said second wall surface for connecting the inside of said ionization chamber and the inside of said mass spectrometer unit; and wherein a rectangular flat door is disposed on said third wall surface for forming an opening that opens to the inside of said ionization chamber and for closing said opening; said door is openable and closeable about a first edge of said rectangular door; a lever is formed on a side surface of a second edge of said door that opposes the first edge of said door, said lever comprising a straight-shaped section that is rotatable about a rotation shaft that is perpendicular to said first edge; one end of said straight-shaped section of the lever is operated by a person taking measurements, the rotation in a forward direction of the one end of the straight-shaped section of the lever by said person taking measurements causing a male part that is formed on said lever to engage with a female part that is formed on said enclosure and become locked thus making said door unable to be opened and closed and the rotation in a reverse direction of the one end of the straight-shaped section of the lever by said person taking measurements causing the male part that is formed on said lever to disengage from the female part that is formed on said enclosure and becoming unlocked thus allowing said door to be opened and closed; and the one end of said straight-shaped section of the lever is rotated in a reverse direction by said person taking measurements to unlock which causes other end of said straight-shaped section of the lever to press against a portion of a third wall surface, creating a force that opens said door.