| 摘要 |
PURPOSE:To detect a sample at a sucking section formed by a needle of an automatic sampler by judging whether a fluid sucked is a liquid, a liquid containing air bubbles or a gas using a difference in physical or chemical nature. CONSTITUTION:This apparatus consists of connector sections 3 and 4 of a light irradiation section 1, a photodetector section 2 and optical elements, a needle 5, a needle 5 fixing section 6, a tube 7, a tube 7 expanding section 8, a packing 9, a block 10 and a comparator 19. The tube 7 is made of a transparent or semi-transparent resin and light emitted from the irradiation section 1 is irradiated into a passage of the tube 7. However, the quantity of transmission light varies depending on whether the fluid is a liquid or a gas and the light with information on this aspect is incident into the photodetector section 2. Thus, outputs of the photodetector section 2 are determined separately for the gas and the liquid beforehand and a comparator 19 for which an intermediate value between the outputs is set is arranged at a rear stage of the photodetector section 2. This enables judgement of whether the fluid in the passage is a gas or liquid by a signal from the photodetector section 2. |
