Patent Number: 047059508
Section: claims

1. A specimen-exchanging apparatus comprising a specimen chamber subjected to a vacuum, a specimen-exchanging chamber connected with said specimen chamber, said specimen-exchanging chamber being openable to ambient air, valve means for sealing and releasing the connection between said specimen chamber and said specimen-exchanging chamber means for exhausting said specimen-exchanging chamber, rotating means for rotating a feed screw means in clockwise and counterclockwise directions, said feed screw means extending within said specimen-exchanging chamber along the longitudinal coaxial direction of both said specimen-exchanging chamber and said specimen chamber, guide means disposed in parallel with said feed screw means, a removable nut means threaded through said feed screw means for moving slidably in a direction from said specimen-exchanging chamber to said specimen chamber and in an opposite direction from said specimen chamber to said specimen-exchanging chamber by a rotataional direction of said feed screw means, said nut means being formed monolithically with a moving means for removing a specimen holder mounted on said guide means and retaining a specimen for movement linearly between said specimen-exchanging chamber and said specimen chamber, and said moving means being provided with a specimen-chucking means for loading and unloading said specimen holder from said nut means. 2. A specimen-exchanging apparatus according to claim 1, wherein said specimen-chucking means includes a lever means for accomplishing a loading and unloading of said specimen holder by switching position thereof. 3. A specimen-exchanging apparatus according to claim 2, further comprising a rotatable shaft means extending through a wall of said specimen-exhanging chamber for rotating said rotating means from the outside to the inside of the specimen-exchanging chamber in a manner so as to maintain a vacuum in the specimen-exchanging chamber. 4. The specimen-exchanging apparatus according to claim 2 further including means for rotating said lever means disposed outside said specimen-exchanging chamber.