| 摘要 |
The invention relates to a metering needle 1, which is intended especially for an automatic chemical analyser. The invention additionally relates to a metering process based upon the use of the said metering needle and to a process for production of the metering needle. The metering needle 1, which comprises a tubular shaft 2 and a flow duct 3 situated inside the same, is characterized according to the invention in that the flow duct 3, before the end 5 of the needle, emerges into at least one outlet opening 4, which is directed to the side of the longitudinal axis of the needle. The end 5 of the needle is preferably conically tapered and closed and the outlet openings 4 can be two or more in number, the said outlet openings being directed at even spacings to different sides of the needle. In metering which is carried out with the needle, the liquid flows issuing in the lateral direction produce a turbulent mixing of the liquid present in a vessel. The needle is produced by means of electroforming by separating out a metal layer onto a needle-shaped mould, working the metal into a needle and removing the mould from the inside of the needle. <IMAGE>
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