부산대학교 도서관

The gas compression/expansion apparatus comprises: a working section for compressing/expanding therein a working gas by pistons each connected with a rod; a drive section including sliders each connected at one end thereof with the rod and connected at one end thereof with a guide for guiding the slider, and a drive mechanism for reciprocating the sliders; and a separator for fluid dynamically separating the working section from the drive section, the separator permitting said rod to pass through said separator. The separator further includes an oil seal arrangement. Formed inside the separator is an intermediate chamber which allows the rod to pass there through. The inner radius of the intermediate chamber is greater than the radius of the rod plus the oil deposited on the rod. The guide includes a guide space formed such that the distance between the slider at its upper dead point and the wall of the separator facing the slider is larger than the thickness of the oil on the slider. The separator also includes an oil return passage for allowing the oil accumulated in the guide space to return to an oil sump. The oil seal arrangement may prevent the oil on the guide from coming into direct contact with the separator and prevent the oil on the rod from entering the working section.