| 摘要 |
A liquid sampler which may be used for collecting samples of arterial blood is preferably in the form of a syringe. A venting passage (25, 31) is defined in the syringe piston (12) so that gas may escape through the venting passage when arterial blood flows into the cylinder space (17) under the influence of the arterial blood pressure. The venting passage is controlled by valve means (19, 21), which automatically close the venting passage when the cylinder space has been filled with blood and the blood starts flowing into the venting passage. The venting passage is closed by liquid resistant valve surface parts, and movement of these surface parts to their closing position is caused by a liquid reacting substance (22) which is exposed to the liquid sample flowing into the venting passage. This liquid reacting substance may, for example, be a material which swells, expands, or is softened when contacted by liquid. Alternatively, the liquid reacting substance may be a liquid soluble material. |
