| 摘要 |
<p>A piston 124 is movable within a cylinder 112 such that its periphery is in contact with the cylinder walls. The base of the cylinder is closed but a valve in the piston selectively allows flow into and out of the region of the cylinder below the piston face. Ideally the piston contacts the liquid. The piston can be manually movable by integral plunger 116 which includes a conduit 118 and passes through a lid 114. The valve can be a ball float 138 sealing against a tapered aperture 136. Alternative seals are a perforated plate coverable by a flexible membrane (figs 1-3) or two perforated plates which can swivel for alignment or obstruction (figs 16). The seal can include a gas permeable but liquid impermeable membrane, and have a further silicone valve above it. The container could decant oil, wine, or soft drinks.</p> |
