| 摘要 |
PURPOSE: To retain a medium in a filling floor where a material to be analyzed and processed passes by making shallower an inside in radial direction than an outside in radial direction in terms of the depth in axial direction of a seal and filling a chromatography medium into a column. CONSTITUTION: A piston comprises a body upper part 11a for limiting the piston properly and a body lower part 11b including the upper cell of a chromatography column. An upper part 11a has an end face 23 that converges toward a lower part, a lower part 11b has an end face 25 that converges toward an upper part, an elastomer seal 27 is included by the both, and the end face of the seal is in trapezoid shape. Also, the maximum diameter of the upper edge cell 11b determined by the lower part of the body of the piston is preferably larger than the diameter of the outer surface of the seal 27 in relaxed state and smaller than the maximum outer diameter of the seal in compressed state. Therefore, when the lower part 11b is pulled up toward the upper part 11a, the seal 27 is compressed and its annular outer surface is bulged outside toward the inner surface in radial direction of a column pipe 3. |
