| 摘要 |
Methods and apparatus are disclosed relating to a mechanical vacuum socket pump (100) used to establish a vacuum in a socket of an artificial limb. In one case, the pump includes a housing (102) within which two pistons (104, 106) coaxially reciprocate. A surface of each of the pistons is linked hydraulically, such that driving one piston causes movement of the other piston through a hydraulic chamber. One piston is also linked to a pneumatic chamber such that movement of that piston draws air from a limb socket or expels air to the atmosphere upon movement of the piston's pneumatic surface. The surface area of the hydraulic surface of this piston is significantly less than the surface area of the pneumatic surface, so a small volumetric displacement of hydraulic fluid may cause a large displacement of air. Thus, the pump efficiently pumps air with minimal compression and extension of the pump as a whole. |
