Automated analyzing device, and dispensing method

Patent metadata

Field	Value
Publication number	US-2025044314-A1
Application number	US-202218718097-A
Country	US
Kind code	A1
Filing date	Nov 29, 2022
Priority date	Jan 6, 2022
Publication date	Feb 6, 2025
Grant date	—

Abstract

An object of the invention is to provide a technique that can accurately determine whether a liquid surface height of a liquid is abnormal when a dispensing probe dispenses the liquid. An automatic analyzer according to the invention sets a normal range and an abnormal range above and below a previously detected liquid surface height, regards a liquid surface height as normal when a liquid surface is detected in the normal range, and regards a liquid surface height as abnormal when a liquid surface is detected in the abnormal range. When a liquid surface is detected above or below a range in which a variation is added to the previously detected liquid surface height, a liquid surface height is also regarded as normal under a predetermined condition.

First claim

1 . An automatic analyzer including a dispensing probe configured to dispense a liquid, the automatic analyzer comprising:
a liquid surface detection unit configured to detect a liquid surface of the liquid; a storage unit configured to store a liquid surface height when the liquid surface has finished lowering by the dispensing probe aspirating the liquid; and a control unit configured to control the dispensing probe, wherein when the liquid surface is detected in a first range formed by a first variation range below the liquid surface height stored by the storage unit and a second variation range above the liquid surface height stored by the storage unit, the control unit determines that the liquid surface is normal, when the liquid surface is detected in a second range below the first variation range, the control unit determines that the liquid surface is normal, when the liquid surface is detected in a third range above the second variation range and a predetermined condition is satisfied, the control unit determines that the liquid surface is normal, and when the liquid surface is detected in a fourth range above the third range or a fifth range below the second range, the control unit determines that the liquid surface is abnormal.

2 . The automatic analyzer according to claim 1 , wherein
the dispensing probe continuously aspirates the liquid housed in a liquid container two times or more, the liquid container includes an opening portion into which the dispensing probe is inserted, and a partition that divides inside of the liquid container into a region below the opening portion and a region outside the opening portion, the predetermined condition is a fact that the liquid surface height stored by the storage unit when the dispensing probe previously aspirates the liquid from the liquid container is in the second range, and when the liquid surface is detected in the third range and the predetermined condition defined based on the liquid container is satisfied, the control unit determines that the liquid surface is normal.

3 . The automatic analyzer according to claim 2 , wherein
when the liquid surface is detected in the third range without satisfying the predetermined condition, the control unit determines that the liquid surface is abnormal.

4 . The automatic analyzer according to claim 1 , wherein
when the liquid surface is not detected before the dispensing probe reaches a lowest point, the control unit determines that the liquid surface is abnormal.

5 . The automatic analyzer according to claim 1 , wherein
the third range is a region wider than the second range.

6 . The automatic analyzer according to claim 1 , wherein
the control unit determines whether the liquid surface is normal according to a change rate of the liquid surface height for each dispensing when the liquid surface lowers due to the dispensing probe aspirating the liquid.

7 . The automatic analyzer according to claim 6 , wherein
the control unit designates an amount by which the dispensing probe aspirates the liquid for each dispensing, and in a case where a difference between a first change rate of a liquid surface height when the liquid surface lowers according to the designated aspiration amount and a second change rate of a liquid surface height of the liquid surface detected by the liquid surface detection unit is equal to or larger than a threshold, the control unit determines that the liquid surface is abnormal.

8 . The automatic analyzer according to claim 6 , wherein
the control unit performs the determination by using only a part of history of detection results of the liquid surface height.

9 . The automatic analyzer according to claim 1 , wherein
the control unit lowers the dispensing probe toward the liquid at a first speed to a speed switching height above the liquid surface height stored by the storage unit, and the control unit detects the liquid surface by the liquid surface detection unit while lowering the dispensing probe at a second speed lower than the first speed after the dispensing probe reaches the speed switching height.

10 . The automatic analyzer according to claim 9 , wherein
the control unit gradually decreases an absolute value of the second speed as time elapses, and the control unit controls the second speed such that the liquid surface detection unit detects the liquid surface in a period in which the absolute value of the second speed is changed.

11 . The automatic analyzer according to claim 1 , wherein
the dispensing probe aspirates the liquid housed in a liquid bottle, and the control unit calculates, for each shape of the liquid bottle, an amount by which the liquid surface lowers every time the dispensing probe aspirates the liquid from the liquid bottle.

12 . The automatic analyzer according to claim 1 , wherein
at least any one of the first range, the second range, the third range, the fourth range, and the fifth range is different for each type of the liquid.

13 . A dispensing method for dispensing a liquid by using a dispensing probe configured to dispense the liquid, the dispensing method comprising:
a step of detecting a liquid surface of the liquid; a step of storing, in a storage unit, a liquid surface height when the detected liquid surface has finished lowering by the dispensing probe aspirating the liquid; and a step of controlling the dispensing probe, wherein in the step of controlling the dispensing probe, when the liquid surface is detected in a first range formed by a first variation range below the liquid surface height stored by the storage unit and a second variation range above the liquid surface height stored by the storage unit, it is determined that the liquid surface is normal, in the step of controlling the dispensing probe, when the liquid surface is detected in a second range below the first variation range, it is determined that the liquid surface is normal, in the step of controlling the dispensing probe, when the liquid surface is detected in a third range above the second variation range and a predetermined condition is satisfied, it is determined that the liquid surface is normal, and in the step of controlling the dispensing probe, when the liquid surface is detected in a fourth range above the third range or a fifth range below the second range, it is determined that the liquid surface is abnormal.

Assignees

• Hitachi High Tech Corp

Inventors

• Kameyama Hiroki
• Mori Takamichi

Classifications

• G01F23/265

  for discrete levels · CPC title

• G01N2035/1025

  Fluid level sensing · CPC title

• G01N35/025

  having a carousel or turntable for reaction cells or cuvettes · CPC title

• G01N35/1009 Primary

  Characterised by arrangements for controlling the aspiration or dispense of liquids · CPC title

• G01N35/1016 Primary

  Control of the volume dispensed or introduced · CPC title