Automatic analysis device

Abstract

Provided is an automatic analysis device with which it is possible to avoid contact between a dispensing nozzle and a specimen container. This automatic analysis device comprises: a specimen disk for holding a specimen container in which a specimen is accommodated; a specimen-dispensing unit for suctioning the specimen from the specimen container, the specimen-dispensing unit having a dispensing nozzle oriented in the vertical direction; an analysis unit for analyzing the specimen; and a control unit for controlling each of the units, the automatic analysis device being characterized by furthermore comprising an imaging unit for capturing an image of the specimen container, and the control unit calculating a central axis of the specimen container using the image captured by the imaging unit and controlling movement of the dispensing nozzle on the basis of the central axis.

Description

automatic analyzer

[0001] The present invention relates to an automatic analyzer for analyzing samples such as blood and urine.

[0002] Automated analyzers are devices that automatically perform qualitative or quantitative analysis of specific components contained in samples such as blood and urine. When a sample is small in volume, the sample may be stored in a sample container placed on top of the blood collection tube used to collect the sample. Compared to blood collection tubes, sample containers have a smaller dead volume, or the maximum amount that can be drawn, making them suitable for handling small amounts of sample. Blood collection tubes come in several different outer diameters, and if the outer diameter of the blood collection tube is smaller than the inner diameter of the hole into which the blood collection tube is inserted, the blood collection tube may tilt.

[0003] Patent document 1 discloses that the amount of liquid and the tilt angle of a container can be determined from an upper image taken from above by a single camera, and that based on the determination results, the collection unit that collects the liquid from the container can be stopped or its height and angle can be adjusted.

[0004] Japanese Patent Application Laid-Open No. 2020-173101

[0005] However, in Patent Document 1, no consideration is given to preventing contact between the dispensing nozzle of the collection unit and the container. If the specimen container above the specimen tube tilts due to the tilt of the specimen tube, this may cause contact between the specimen container and the dispensing nozzle, which may interfere with the operation of the automatic analyzer.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an automatic analyzer that can prevent contact between a dispensing nozzle and a sample container.

[0007] In order to achieve the above object, the present invention provides an automatic analyzer comprising a sample disk for holding sample containers containing samples, a sample dispensing unit having a vertically oriented dispensing nozzle that aspirates the sample from the sample container, an analysis unit that analyzes the sample, and a control unit that controls each unit, and further comprising an imaging unit that images the sample container, wherein the control unit calculates the central axis of the sample container using an image captured by the imaging unit and controls the movement of the dispensing nozzle based on the central axis.

[0008] According to the present invention, an automatic analyzer can be provided that can prevent contact between a dispensing nozzle and a sample container.

[0009] FIG. 1 is a diagram illustrating an example of the overall configuration of an automatic analyzer. FIG. 2 is a diagram illustrating a sample disk and a sample dispensing unit. FIG. 3 is a diagram illustrating a processing flow of Example 1. FIG. 4 is a diagram illustrating an example of an image of a sample container photographed from above by an imaging unit. FIG. 5 is a diagram illustrating an example of an image of a tilted sample container photographed from a horizontal direction. FIG. 6 is a diagram illustrating movement of a dispensing nozzle. FIG. 7 is a diagram illustrating a case where the dispensing nozzle is tilted.

[0010] A preferred embodiment of an automatic analyzer according to the present invention will now be described with reference to the accompanying drawings. The automatic analyzer is an apparatus for analyzing samples such as blood or urine using a reaction liquid obtained by reacting a sample with a reagent.

[0011] An example of the overall configuration of an automatic analyzer 1 according to Example 1 will be described using Figure 1. The automatic analyzer 1 includes a sample disk 4, a reagent disk 7, a sample dispensing unit 11, a reagent dispensing unit 12, a reaction disk 10, an analysis unit 14, and a control unit 17. Each unit will be described below.

[0012] The specimen disk 4 is a rotating disk that holds a plurality of blood collection tubes 15 containing specimens 2 such as blood or urine. The blood collection tubes 15 are arranged at equal intervals around the circumference of the specimen disk 4. When the amount of specimen 2 is small, specimen containers 3 are used that have a smaller dead volume, or suction limit, compared to the specimen tubes 15. The specimen containers 3 are placed on top of the specimen tubes 15. The specimen containers 3 and the specimen tubes 15 are made of a transparent material. As the specimen disk 4 rotates, the specimen tubes 15 and specimen containers 3 are transported to the suction position, which is a position accessible by the specimen dispensing unit 11.

[0013] The specimen dispensing unit 11 aspirates specimen 2 from specimen containers 3 transported by the rotation of the specimen disk 4, and dispenses the aspirated specimen 2 into reaction containers 9 arranged on the reaction disk 10. Details of the specimen disk 4 and the specimen dispensing unit 11 will be described later with reference to FIG. 2.

[0014] The reaction disk 10 keeps the temperature of a plurality of reaction vessels 9 arranged in a circumferential manner within a predetermined range, and transports the reaction vessels 9 into which the specimens 2 have been discharged to a position accessible by the reagent dispensing unit 12 .

[0015] The reagent disk 7 stores a plurality of reagent bottles 6 containing reagents 5 used in analyzing the specimen 2 at a predetermined temperature range.

[0016] The reagent dispensing unit 12 aspirates the reagent 5 from the reagent bottle 6 stored on the reagent disk 7 and dispenses the reagent 5 into the reaction vessel 9 containing the sample 2 .

[0017] The reaction vessel 9 containing the specimen 2 and reagent 5 is transported by the rotation of the reaction disk 10 to a position accessible to the stirring unit 13. The stirring unit 13 stirs the specimen 2 and reagent 5 in the reaction vessel 9. The warming by the reaction disk 10 and the stirring by the stirring unit 13 promote the reaction between the specimen 2 and reagent 5 in the reaction vessel 9, producing a reaction liquid 8. The reaction disk 10 transports the reaction vessel 9 containing the reaction liquid 8 to the analysis unit 14.

[0018] The analysis unit 14 measures the physical properties of the reaction solution 8 contained in the reaction vessel 9, such as the amount of luminescence, the amount of scattered light, the amount of transmitted light, the current value, the voltage value, etc. Note that the physical properties measured are not limited to these. The physical properties measured by the analysis unit 14 are transmitted to the control unit 17. Note that the reaction vessel 9 after measurement by the analysis unit 14 is washed by the washing unit 16.

[0019] The control unit 17 is a device that receives the physical properties transmitted from the analysis unit 14, outputs and stores the analysis results, and controls each unit included in the automatic analyzer 1, and is configured by, for example, a so-called computer.

[0020] 2, the specimen disk 4 and the specimen dispensing unit 11 will be further described. An imaging unit 20 is provided near the specimen disk 4.

[0021] The specimen disk 4 is provided with a plurality of holes 21 into which the blood collection tubes 15 are inserted. The blood collection tubes 15 are held on the specimen disk 4 by being inserted into the holes 21. The inner diameter of the holes 21 into which the blood collection tubes 15 are inserted exceeds the maximum value of the outer diameters, which vary depending on the type of blood collection tube 15. If the outer diameter of the blood collection tube 15 is too small compared to the inner diameter of the holes 21, the blood collection tube 15 will tilt, and the specimen container 3 placed on top of the blood collection tube 15 will also tilt.

[0022] The sample dispensing unit 11 has a dispensing nozzle 11a, an arm 11b, and a rotating shaft 11c. The dispensing nozzle 11a is a thin tube that aspirates a sample from a sample container 3 that has been moved to the aspirating position 22 by the rotation of the sample disk 4. It is oriented vertically and connected to one end of the arm 11b. The rotating shaft 11c is connected to the other end of the arm 11b, and rotation of the rotating shaft 11c causes the dispensing nozzle 11a to move in an arc in a horizontal plane. If the arm 11b has a multi-joint structure or if the rotating shaft 11c moves freely in the horizontal plane, the dispensing nozzle 11a will move freely in the horizontal plane. Furthermore, the dispensing nozzle 11a also rises and falls with the up and down movement of the rotating shaft 11c.

[0023] The photographing unit 20 is a camera that photographs the specimen container 3 that has been moved to the suction position 22. When there is only one photographing unit 20, the specimen container 3 is photographed from above. Note that multiple photographing units 20 may be provided, and for example, cameras that photograph from the horizontal direction are provided at different azimuth angles. It is preferable that the difference in azimuth angles between two cameras photographing from the horizontal direction is 90 degrees. The images acquired by the photographing unit 20 are transmitted to the control unit 17.

[0024] The control unit 17 calculates the central axis of the specimen container 3 using the image transmitted from the photographing unit 20, and controls the movement of the dispensing nozzle 11a based on the calculated central axis so that the dispensing nozzle 11a does not come into contact with the specimen container 3.

[0025] An example of the processing flow of the first embodiment will be described step by step with reference to FIG.

[0026] (S301) The control unit 17 rotates the sample disk 4 and moves the sample container 3 to the aspirating position 22.

[0027] (S302) The control unit 17 causes the photographing unit 20 to photograph the specimen container 3 that has been moved to the aspirating position 22.

[0028] (S303) The control unit 17 calculates the central axis of the specimen container 3 using the image acquired by the imaging unit 20.

[0029] An example of calculating the central axis of the specimen container 3 will be described using Figure 4. Figure 4 illustrates images of the specimen container 3 captured from above by a single imaging unit 20, with (a) showing a case in which the specimen container 3 is tilted and (b) showing a case in which the specimen container 3 is upright. The control unit 17 extracts an edge region 41 at the upper end of the specimen container 3 and a liquid surface region 42 of the specimen 2 based on pixel values ​​of the images illustrated in Figure 4. In Figure 4, the edge region 41 is indicated by vertical lines, and the liquid surface region 42 is indicated by diagonal lines. The control unit 17 also calculates center points 43 and 44 of the extracted edge region 41 and liquid surface region 42, respectively.

[0030] When the sample container 3 is upright, the edge region 41 and the liquid surface region 42 have a circular shape, whereas when the sample container 3 is tilted, both shapes become ellipses. Furthermore, the greater the tilt angle of the central axis of the sample container 3 with respect to the vertical line, the shorter the minor axis of both ellipses. Therefore, the tilt angle of the central axis of the sample container 3 can be determined based on the length of the minor axis determined by approximating the edge region 41 and the liquid surface region 42 to an ellipse.

[0031] The tilt angle of the central axis of the sample container 3 may be determined based on the distance between the center point 43 of the edge region 41 and the center point 44 of the liquid surface region 42. In an upright sample container 3, the center points 43 and 44 coincide, whereas in a tilted sample container 3, the two center points do not coincide, and the greater the tilt angle of the central axis of the sample container 3, the longer the distance between the center points. Therefore, the tilt angle of the central axis of the sample container 3 may be determined based on the distance between the center points 43 and 44. Furthermore, the tilt orientation of the sample container 3 can also be determined based on the positions of the two center points. For example, in FIG. 4A, the line connecting the center points 43 and 44 represents the tilt orientation of the sample container 3.

[0032] Furthermore, the control unit 17 determines the liquid level of the sample 2 based on the area of ​​the liquid level region 42. The liquid level of the sample 2 increases as the amount of sample 2 in the sample container 3 increases, and the area of ​​the liquid level region 42 increases. Therefore, the liquid level of the sample 2 is determined based on the area of ​​the liquid level region 42. Even if the sample container 3 is tilted and the shape of the liquid level region 42 becomes elliptical, the major axis of the ellipse does not change, and therefore the liquid level of the sample 2 may be determined based on the length of the major axis determined by approximating the liquid level region 42 to an ellipse.

[0033] Another example of calculation of the central axis of the specimen container 3 will be described using Fig. 5. Fig. 5 shows an image of a tilted specimen container 3 photographed from the horizontal direction. The control unit 17 extracts the area of ​​the specimen container 3 and the liquid surface 52 of the specimen 2 based on the pixel values ​​of the image shown in Fig. 5. In Fig. 5, the area of ​​the specimen container 3 is shown as a shaded area.

[0034] Since the shape of the specimen container 3 is known, the central axis 51 of the specimen container 3 is determined based on the extracted area of ​​the specimen container 3. Then, the angle θ between the vertical line 50 passing through the center of the hole 21 into which the blood collection tube 15 is inserted and the central axis 51 of the specimen container 3 is calculated. The angle θ between the vertical line 50 and the central axis 51 is calculated for each image captured at a different azimuth angle, and the tilt angle of the specimen container 3 is determined from these angles. Furthermore, the liquid level height is determined based on the extracted liquid level 52.

[0035] (S304) The control unit 17 calculates the aspiration start point and the aspiration end point based on the central axis 51 of the sample container 3 calculated in S303. The aspiration start point is the point where the tip of the dispensing nozzle 11a is located when the dispensing nozzle 11a starts aspiration of the sample 2. The aspiration end point is the point where the tip of the dispensing nozzle 11a is located when the dispensing nozzle 11a stops aspiration of the sample 2.

[0036] The calculation of the aspiration start point and the aspiration end point will be described using Figure 6. Figure 6 shows a side view of a tilted sample container 3 and the dispensing nozzle 11a, in which (a) shows the state before the dispensing nozzle 11a descends, (b) shows the state when the tip of the dispensing nozzle 11a has reached the aspiration start point 61, and (c) shows the state when the tip of the dispensing nozzle 11a has reached the aspiration end point 62.

[0037] As shown in Figure 6(a), before descending, the dispensing nozzle 11a is positioned directly above the center of the hole 21 into which the blood collection tube 15 is inserted, i.e., on the vertical line 50. If the specimen container 3 is tilted as shown in Figure 6(a), the dispensing nozzle 11a descending along the vertical line 50 will come into contact with the specimen container 3, and therefore the dispensing nozzle 11a must be moved to avoid contact.

[0038] 6(b), the suction start point 61 is a point on the central axis 51, and is located at a depth d1 from the liquid surface 52. Therefore, the coordinates of the suction start point 61 are calculated based on the central axis 51, the liquid surface height of the sample 2, and the depth d1. The depth d1 is set in advance as the length by which the dispensing nozzle 11a is immersed in the sample 2, and is set to, for example, 2 mm to 3 mm.

[0039] 6(c), the aspiration end point 62 is a point on the central axis 51, and is located at a depth d2 from the aspiration start point 61. Therefore, the coordinates of the aspiration end point 62 are calculated based on the central axis 51, the aspiration start point 61, and the depth d2. The depth d2 is calculated based on the amount of sample 2 aspirated by the dispensing nozzle 11a and the area of ​​the cross section of the sample container 3 perpendicular to the central axis 51.

[0040] (S305) The control unit 17 lowers the dispensing nozzle 11a based on the central axis 51 of the specimen container 3 so that the tip of the dispensing nozzle 11a reaches the suction start point 61. For example, the control unit 17 controls the dispensing nozzle 11a so that the tip of the dispensing nozzle 11a moves along the central axis 51. By moving the tip of the dispensing nozzle 11a obliquely along the central axis 51, contact between the dispensing nozzle 11a and the specimen container 3 can be avoided.

[0041] If the dispensing nozzle 11a only traces an arcuate trajectory in a horizontal plane, the movement of the dispensing nozzle 11a may be linked to the rotation of the specimen disk 4 so that the tip of the dispensing nozzle 11a is aligned with the central axis 51. Furthermore, if the movement of the dispensing nozzle 11a is linked to the rotation of the specimen disk 4, it is preferable that the arcuate trajectory of the dispensing nozzle 11a and the rotation direction of the specimen disk 4 are perpendicular to each other at the suction position 22. By making the two perpendicular to each other, it becomes easier to move the tip of the dispensing nozzle 11a along the central axis 51 of the specimen container 3.

[0042] Alternatively, the control unit 17 may move the dispensing nozzle 11a horizontally to directly above the aspiration end point 62 and then lower it. This type of control also makes it possible to avoid contact between the dispensing nozzle 11a and the sample container 3. Furthermore, this requires simpler control than when the tip of the dispensing nozzle 11a is moved obliquely along the central axis 51.

[0043] If the tilt angle of the sample container 3 is too large, the movement of the dispensing nozzle 11a may be stopped. For example, in the image shown in FIG. 4 , if the minor axis of the liquid surface area 42 is equal to or smaller than the outer diameter of the dispensing nozzle 11a, contact between the vertically oriented dispensing nozzle 11a and the sample container 3 cannot be avoided, so a warning may be issued and the movement of the dispensing nozzle 11a may be stopped. Incidentally, contact between the dispensing nozzle 11a and the sample container 3 can be avoided by tilting the dispensing nozzle 11a according to the tilt angle of the sample container 3, as shown in FIG. 7 . However, this is not preferable because it may result in a decrease in suction accuracy or an increase in the length d3 by which the dispensing nozzle 11a is immersed in the sample 2.

[0044] (S306) The control unit 17 causes the dispensing nozzle 11a to aspirate the specimen 2 contained in the specimen container 3. As the specimen 2 is aspirated by the dispensing nozzle 11a, the liquid level 52 of the specimen 2 descends. Therefore, the control unit 17 causes the dispensing nozzle 11a to descend to the aspirating end point 62 in accordance with the descending liquid level 52. It is preferable that the descending speed of the dispensing nozzle 11a be set in accordance with the descending speed of the liquid level.

[0045] (S307) The control unit 17 raises the dispensing nozzle 11a and returns it to its initial position. The tip of the dispensing nozzle 11a may move along the central axis 51, or the nozzle may rise vertically and then move horizontally. The dispensing nozzle 11a, which has been returned to its initial position, moves to the reaction disk 10 by the rotation of the rotation shaft 11c, and dispenses the aspirated sample 2 into the reaction vessel 9.

[0046] According to the process flow described with reference to FIG. 3, the sample 2 can be aspirated while avoiding contact between the dispensing nozzle 11a and the sample container 3.

[0047] The above describes the embodiments of the present invention. The present invention is not limited to the above embodiments, and the components may be modified within the scope of the gist of the invention. Furthermore, multiple components disclosed in the above embodiments may be appropriately combined. Furthermore, some components may be deleted from all the components shown in the above embodiments.

[0048] 1: automatic analyzer, 2: specimen, 3: specimen container, 4: specimen disk, 5: reagent, 6: reagent bottle, 7: reagent disk, 8: reaction liquid, 9: reaction vessel, 10: reaction disk, 11: specimen dispensing unit, 11a: dispensing nozzle, 11b: arm, 11c: rotating shaft, 12: reagent dispensing unit, 13: stirring unit, 14: analysis unit, 15: blood collection tube, 16: washing unit, 17: control unit, 20: imaging unit, 21: hole, 22: suction position, 41: edge region, 42: liquid surface region, 43: center point, 44: center point, 50: vertical line, 51: central axis, 52: liquid surface, 61: suction start point, 62: suction end point

Claims

1. An automatic analyzer comprising: a sample disk that holds sample containers that contain samples; a sample dispensing unit that has a vertically oriented dispensing nozzle that aspirates the sample from the sample container; an analyzing unit that analyzes the sample; and a control unit that controls each unit, wherein the automatic analyzer further comprises an imaging unit that images the sample container, and the control unit calculates the central axis of the sample container using an image taken by the imaging unit and controls the movement of the dispensing nozzle based on the central axis.

2. An automatic analyzer according to claim 1, wherein the control unit controls the tip of the dispensing nozzle to move along the central axis.

3. An automatic analyzer according to claim 2, wherein the control unit links the movement of the dispensing nozzle with the operation of the specimen disk.

4. An automatic analyzer according to claim 3, wherein the specimen disk is a rotating disk that holds a plurality of specimen containers along its circumferential direction, the dispensing nozzle describes an arcuate trajectory in a horizontal plane, and at the position where the specimen is aspirated, the direction of rotation of the specimen disk and the arcuate trajectory are perpendicular to each other.

5. An automatic analyzer according to claim 1, wherein the control unit moves the dispensing nozzle horizontally to directly above the suction end point and then lowers it.

6. An automatic analyzer according to claim 1, wherein the photographing unit acquires the image by photographing the specimen container from above, and the control unit stops the movement of the dispensing nozzle when the minor axis of the liquid surface area of ​​the specimen extracted from the image is equal to or smaller than the outer diameter of the dispensing nozzle.

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