阅读说明：本技术 自动分析装置 (Automatic analyzer ) 是由 堀江阳介 吉村保广 风间敦 石泽雅人 山本谕 于 2018-12-26 设计创作，主要内容包括：本发明提供具备能够使用超声波来高精度地检测各种高度的样本容器内的液面的液面检测功能的自动分析装置。具备：搬运架(22),其载置并搬运放入有样本的样本容器；固定的超声波距离传感器(200),其测定载置于搬运架的样本容器内的液面位置；声波导向件(204、205),其配置于样本容器与超声波距离传感器之间,抑制从超声波距离传感器发送出的声波的扩散；以及声波导向件控制部,其根据超声波距离传感器与样本容器之间的距离来进行声波导向件的长度调整或长度切换。(The invention provides an automatic analyzer having a liquid level detection function capable of detecting liquid levels in sample containers of various heights with high accuracy using ultrasonic waves. The disclosed device is provided with: a carrier (22) for carrying and transporting a sample container in which a sample is placed; a fixed ultrasonic distance sensor (200) for measuring the position of the liquid surface in the sample container placed on the carrier; acoustic wave guides (204, 205) disposed between the sample container and the ultrasonic distance sensor, and configured to suppress diffusion of acoustic waves transmitted from the ultrasonic distance sensor; and an acoustic wave guide control unit that adjusts or switches the length of the acoustic wave guide according to the distance between the ultrasonic distance sensor and the sample container.)

1. An automatic analyzer, comprising:

a carrier for carrying a sample container in which a sample is placed;

a fixed ultrasonic distance sensor for measuring a liquid level position in the sample container placed on the carrier;

a sound wave guide disposed between the sample container and the ultrasonic distance sensor, for suppressing diffusion of the sound wave transmitted from the ultrasonic distance sensor; and

and an acoustic wave guide control unit that adjusts or switches the length of the acoustic wave guide according to the distance between the ultrasonic distance sensor and the sample container.

2. The automatic analysis device according to claim 1,

the acoustic wave guide is multi-stage and can be extended and retracted.

3. The automatic analysis device according to claim 1,

the acoustic wave guide includes a plurality of acoustic wave guides having different lengths,

the acoustic wave guide control unit may dispose one acoustic wave guide selected from the plurality of acoustic wave guides having different lengths between the sample container and the ultrasonic distance sensor.

4. The automatic analysis device according to claim 3,

the plurality of acoustic wave guides having different lengths are fixed to the rotating circular plate,

the length of the acoustic wave guide disposed between the sample container and the ultrasonic distance sensor is switched by rotating the rotating disk.

5. The automatic analysis device according to claim 1,

the ultrasonic distance sensor has a cylindrical outer shape,

the acoustic wave guide has a cylindrical shape having an inner diameter larger than an outer diameter of the ultrasonic distance sensor, and is movable up and down so as to surround the ultrasonic distance sensor.

6. The automatic analysis device according to claim 1,

a storage part for registering the height information of the sample container in advance,

the acoustic wave guide control unit controls the acoustic wave guide so that a distance between the acoustic wave guide and the sample container is a predetermined value or less, using the height information registered in the storage unit, when the sample container is positioned below the ultrasonic distance sensor.

7. The automatic analysis device according to claim 1,

the ultrasonic distance sensor is provided with an inclination determination unit which determines the inclination of the sample container based on the heights of at least two points of the upper edge of the sample container measured by the ultrasonic distance sensor.

8. The automatic analysis device according to claim 1,

a sample dispensing mechanism having a vertically movable nozzle for dispensing a sample from the sample container mounted on the carrier,

adjusting an operation parameter of the sample dispensing mechanism for lowering the nozzle into the sample container based on information of the liquid surface position measured by the ultrasonic distance sensor.

9. The automatic analysis device according to claim 8,

has a capacitance sensor for detecting the contact of the nozzle with the liquid surface,

the liquid surface position measured by the ultrasonic distance sensor is compared with the liquid surface position detected by the capacitance sensor.

10. The automatic analysis device according to claim 7,

a sample dispensing mechanism having a vertically movable nozzle for dispensing a sample from the sample container mounted on the carrier,

after determining the inclination of the sample container, it is determined whether or not the nozzle is in contact with the sample container.

11. The automatic analysis device according to claim 10,

when it is determined that there is the risk, the horizontal movement amount of the nozzle is corrected so as to avoid contact with the sample container.

12. The automatic analysis device according to claim 7, comprising:

a sample dispensing mechanism having a vertically movable nozzle and configured to dispense a sample from the sample container placed on the transport rack; and

a capacitance sensor for detecting contact between the nozzle and the liquid surface,

the insensitive region of the capacitance sensor is set based on the inclination of the sample container.

13. The automatic analysis device according to claim 1,

the dead zone of the ultrasonic distance sensor is switched according to the length of the acoustic wave guide.

Technical Field

The present invention relates to an automatic analyzer having a function of measuring a liquid level position of a sample in a sample container in a non-contact manner.

Background

In an automatic analyzer, a sample container such as a blood collection tube or a sample cup, in which a sample is placed, is loaded into the analyzer in order to analyze the sample such as blood. In the apparatus, the sample in each container is dispensed (dispensed as a predetermined amount of processing), and mixed with a reagent to perform component analysis. For dispensing, a long and narrow nozzle is used, and in order to dispense with high accuracy, the liquid surface position of the sample is detected by a capacitance type sensor as described in patent document 1. However, the capacitance sensor may have an error in detection due to a charged state around the blood collection tube, the sample cup, or the like. Further, since the liquid surface position is detected first when the nozzle approaches the liquid surface, the lowering control is performed to stop the nozzle suddenly. Therefore, a sensing method capable of detecting the liquid level in a non-contact manner has been studied. In the method using a laser for liquid level detection in the non-contact method, since a change in reflectance of a liquid such as blood having a different color affects measurement accuracy and the cost for mounting the liquid to the apparatus is high, a method using an ultrasonic wave has been developed as described in patent document 2.

Disclosure of Invention

Problems to be solved by the invention

In the distance measurement using the ultrasonic wave, the distance is calculated from the time when the acoustic wave emitted from the piezoelectric element in the ultrasonic distance sensor is reflected at the liquid surface and returned. In the case of a blood collection tube, the inner diameter is about 10mm, and when an ultrasonic distance sensor is provided above the blood collection tube to detect the liquid level, the possibility that the sound wave first returns from the upper edge of the blood collection tube is high. Further, there is a possibility that sound waves are reflected off the liquid surface, such as the edge and side surface of the adjacent blood collection tube, and the upper surface of the carrier on which the blood collection tube is placed. When measuring the distance to an object within a desired range by an ultrasonic distance sensor, there is a method of mounting a horn in order to concentrate sound waves and improve directivity. Further, it is also possible to provide an insensitivity band at the time of transmission of the acoustic wave to reception of the reflected wave, and perform signal processing regardless of the reflected wave from a certain range of distance.

However, for example, in an automatic blood analyzer, blood collection tubes having various heights of about 50mm at the shortest to 100mm at the longest are used, and the height difference is 50mm or more. The height of the liquid surface in the blood collection tube is also various, and for example, the minimum liquid amount in the blood collection tube having a height of 100mm is about 10mm from the bottom, the maximum liquid amount is about 90mm from the bottom, and the height difference is also about 80 mm. In this way, in order to measure the liquid level position in the blood collection tube under the condition that the blood collection tube has a difference in height, it is necessary to fix the sensor in conformity with the longest blood collection tube. However, if the sensor is fixed in conformity with the longest blood collection tube, the sensor and the blood collection tube are separated by 50mm or more in the measurement of the shortest blood collection tube, and therefore, even when the speaker is mounted, the sound wave is diffused. The distance between the horn and the blood collection tube can also be shortened by moving the sensor itself up and down, but if the sensor itself moves, a positioning error of the sensor is included in a measurement error, and therefore, the sensor is not suitable for measurement requiring accuracy.

Further, even if a dead band is provided in the signal processing, since the range of the liquid surface where the position is unknown is large, the distance between the blood collection tube and the carrier around which the signal should be removed and the range of the liquid surface to be measured may overlap, and setting is difficult. When signal processing is performed using the signal level (voltage) of the reflected wave to determine whether the reflected wave is reflected from the liquid surface or an object other than the liquid surface, it is necessary to take into account a change in the signal level of the reflected wave due to the inclination of the blood collection tube or the carrier, which results in a complicated system.

The invention provides an automatic analyzer having a liquid level detection function capable of accurately measuring the liquid level position in a sample container of various heights using ultrasonic waves.

Means for solving the problems

An automatic analyzer according to the present invention includes: a carrier for carrying a sample container in which a sample is placed; a fixed ultrasonic distance sensor for measuring the position of the liquid surface in the sample container placed on the carrier; a sound wave guide disposed between the sample container and the ultrasonic distance sensor, and configured to suppress diffusion of the sound wave transmitted from the ultrasonic distance sensor; and an acoustic wave guide control unit that adjusts or switches the length of the acoustic wave guide according to the distance between the ultrasonic distance sensor and the sample container.

The effects of the invention are as follows.

The liquid surface position in the sample container of various heights can be measured with high accuracy using ultrasonic waves.

Problems, structures, and effects other than those described above will become apparent from the following description of the embodiments.

Drawings

Fig. 1 is a schematic diagram showing a configuration example of an automatic blood analyzer.

Fig. 2 is a schematic view showing a first embodiment of a liquid level detection mechanism together with a comparative example.

Fig. 3 is a schematic diagram showing an example of a signal waveform obtained from the ultrasonic distance sensor.

Fig. 4 is a schematic diagram showing a second embodiment of the liquid level detection mechanism.

Fig. 5 is a schematic diagram showing a third embodiment of the liquid level detection mechanism.

Fig. 6 is a schematic diagram showing a configuration example of the liquid level detection system.

Fig. 7 is a schematic diagram showing a configuration example of the liquid level detection system.

Fig. 8 is a diagram showing an example of the processing flow of the liquid level detection system.

Fig. 9 is a schematic diagram showing a state of correction of the horizontal movement amount of the nozzle.

Fig. 10 is a schematic diagram showing an example of the output and the insensitive area setting of the electrostatic capacity sensor.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the automatic analyzer of the present invention, a biological sample such as blood or urine is analyzed. Hereinafter, an embodiment of the present invention will be described by way of an automatic blood analyzer that uses blood as a biological sample and a blood collection tube as a sample container. However, this is merely a simple example, and the present invention is not intended to be limited to the automatic blood analyzer.

Fig. 1 is a schematic diagram showing a configuration example of an automatic blood analyzer. Fig. 1 (a) is a schematic plan view of the apparatus, fig. 1 (b) is a schematic diagram of the reagent dispensing mechanism 14, fig. 1 (c) is a schematic diagram of the sample dispensing mechanism 15, and fig. 1 (d) is a schematic diagram of the blood collection tube 21 mounted on the carrier 22.

The automatic blood analyzer 10 of the present embodiment includes: a reagent disk 12 on which a plurality of reagent containers 11 are mounted; a reaction tray 13 provided with a plurality of reaction units 26; a reagent dispensing mechanism 14; a sample dispensing mechanism 15; a carrier 22 for carrying the blood collection tubes 21 as sample containers; a loading line 16 for loading the carrier 22 into the apparatus; a recovery line 17 for recovering the carrier 22; a conveying line 19 for conveying the conveying frame 22; a barcode reader 30 for reading a barcode 29 attached to the blood collection tube 21; and a liquid level detection mechanism 23 for measuring the liquid level position in the blood collection tube 21 on the transport line 19. As shown in fig. 1 (b), the reagent dispensing mechanism 14 includes a nozzle 24 for dispensing a reagent, and suctions the reagent from the reagent container 11 and discharges the reagent to the reaction cell 26. As shown in fig. 1 (c), the sample dispensing mechanism 15 includes a nozzle 25 for dispensing a sample, and suctions a blood sample from the blood collection tube 21 and discharges the blood sample to the reaction cell 26. The nozzle 25 is vertically movable by an arm of the sample dispensing mechanism 15. As shown in fig. 1 (d), the carrier 22 carries a plurality of blood collection tubes 21 containing samples. A barcode 29 in which an ID for identifying each blood collection tube is recorded is attached to the blood collection tube 21. The sample is a sample derived from blood such as serum or whole blood.

The reaction unit 26 provided in the reaction disk 13 is a transparent container, and the concentration of the reaction between the sample and the reagent discharged into the reaction unit 26 is measured as absorbance by a lamp 27 and an absorptiometer 28 disposed across the reaction unit 26. The information of the barcode 29 attached to the blood collection tube 21 is read by the barcode reader 30 located on the transport line during transport, and is used for determining the inspection item for each blood collection tube 21. The automatic analyzer includes an operation unit for operating devices such as a PC and a control board, but not shown in fig. 1.

The sample dispensing mechanism 15 moves the nozzle 25 for the sample from a suction position where the sample is sucked from the blood collection tube 21 mounted on the carrier 22 to a discharge position where the sample is discharged to the reaction cell 26 of the reaction disk 13 by the rotation operation of the arm. In the suction position and the discharge position, the sample dispensing mechanism 15 lowers the nozzle 25 in accordance with the height of the blood collection tube 21 or the reaction disk 13. The nozzle 25 incorporates a known capacitance sensor, and the contact of the nozzle 25 with the liquid surface in the blood collection tube 21 can be detected by monitoring the capacitance that changes when the tip of the nozzle 25 approaches the liquid surface in the blood collection tube 21. Here, the nozzle 25 of the sample dispensing mechanism 15 is cleaned to prevent contamination after a sample is aspirated from one blood collection tube 21 and discharged to the reaction unit 26, and before the nozzle approaches another blood collection tube 21. If the tip of the nozzle 25 is too deep into the sample from the liquid surface, time is required for cleaning, and the productivity of analysis is lowered. Therefore, it is necessary to reliably measure the liquid surface position in the blood collection tube 21 and control the penetration depth of the nozzle tip into the sample. The carrier 22 is intermittently movable by the carrier line 19. That is, when at least the nozzle 25 of the sample dispensing mechanism 15 is positioned at the suction position, the carrier 22 on which the blood collection tube is placed is stopped.

In the present embodiment, the position of the liquid surface in the blood collection tube 21 on the transport rack 22 transported by the transport line 19 is measured by the liquid surface detection mechanism 23 before the sample dispensing mechanism 15 performs the dispensing operation. Therefore, the position of the liquid surface in the blood collection tube 21 is known before the sample dispensing mechanism 15 lowers the nozzle 25. That is, the lowering operation of the nozzle 25 is not performed with respect to an unknown liquid surface position, but the lowering operation of the nozzle 25 can be performed with respect to a known liquid surface position. When the lowering operation of the nozzle is controlled only by the capacitance sensor, the nozzle 25 needs to be stopped by rapidly decelerating the nozzle at the timing of approaching the liquid surface, and is likely to vibrate in the vertical direction. The vibration is caused by, for example, tilting of an arm holding the nozzle 25 of the sample dispensing mechanism 15, or deformation of a belt wheel mechanism for driving the sample dispensing mechanism 15 up and down. However, if the liquid surface position is known before the nozzle 25 is lowered, a deceleration method for reducing the vibration of the nozzle 25 can be selected. The deceleration method for reducing the vibration includes the following methods: for example, the vertical vibration frequency of the nozzle 25 is measured in advance, and the lowering operation of the arm of the sample dispensing mechanism 15 is decelerated to an integral multiple of the reciprocal of the vibration frequency. Alternatively, the acceleration may be stopped by simply suppressing the amount of change in the acceleration.

Fig. 2 is a schematic view showing a first embodiment of a liquid level detection mechanism together with a comparative example. Fig. 2 (a) and (b) are schematic diagrams showing a configuration example of a multistage stretchable acoustic wave guide in the liquid level detection mechanism 23, and fig. 1 (c) is a schematic diagram showing a comparative example.

The ultrasonic distance sensor 200 used in the liquid level detection mechanism 23 of the present embodiment includes a signal processing unit 201, an element unit 202, and a cylindrical unit 203. The signal processing unit 201 includes a circuit that processes transmission and reception of the acoustic wave by the piezoelectric element located in the element unit 202, calculates a distance from the liquid surface from a time of transmission and reception of the acoustic wave, and outputs a voltage corresponding to the distance. The circuit can also be provided at a position away from the liquid surface detection mechanism 23, but is desirably disposed in the vicinity of the element portion 202 in order to suppress the influence of signal noise. The piezoelectric element in the element portion 202 has a circular shape. The cylindrical portion 203 is used for connection between the element portion 202 and the first acoustic wave guide 204 described below, but the cylindrical portion 203 and the first acoustic wave guide 204 do not need to be in contact. When the diameter of the element portion 202 is smaller than the diameter of the first acoustic wave guide 204, the cylindrical portion 203 is not necessary.

The liquid surface detection mechanism 23 of the present embodiment includes an expandable acoustic wave guide constituted by a nested first acoustic wave guide 204 and a nested second acoustic wave guide 205. The first acoustic guide 204 located above is smaller in diameter than the second acoustic guide 205 located below, and is connected and fixed to the base 206 on which the ultrasonic distance sensor 200 is fixed. The first acoustic wave guide 204 may be fixed to a base different from the ultrasonic distance sensor. The second acoustic waveguide 205 is fixed to the up-down mechanism 207 and is movable in the up-down direction. The up-down mechanism 207 may be of a motor-driven pulley mechanism type, a motor-driven ball screw type, or a method of moving up and down using a plurality of solenoids having different lengths. By moving the second acoustic waveguide 205 in the vertical direction, the length of the entire acoustic waveguide can be adjusted.

In the present embodiment, since the ultrasonic distance sensor 200 is fixed to the base 206 and the relative distance from the blood collection tube 21 does not change, the positioning accuracy of the up-down mechanism 207 does not affect the detection accuracy of the liquid level. Therefore, the up-down mechanism 207 does not require high-precision positioning. Therefore, the parts and actuators can be selected in a low-cost range with a low grade. Further, since the ultrasonic distance sensor 200 is fixed and only the acoustic wave guide moves, and the movable portion of the acoustic wave guide does not contact the ultrasonic distance sensor, it is possible to reduce the influence of a positioning error and vibration noise caused by the position adjustment.

The material of the cylindrical acoustic wave guide is not particularly limited, and for example, the cylindrical acoustic wave guide can be made of metal, plastic, or the like. In order to prevent components such as blood adhering to blood collection tube 21 from adhering to second sound guiding member 205, distance d between second sound guiding member 205 and blood collection tube 21 is preferably set to be short. Although the frequency and voltage of the ultrasonic distance sensor 200 used vary, the liquid level in the blood collection tube 21 can be detected even if the distance d between the second acoustic waveguide 205 and the blood collection tube 21 is about 5 mm. Of course, if the outer diameter of the second acoustic waveguide 205 is smaller than the inner diameter of the blood collection tube 21 and the non-contact control is possible, the liquid level detection can be performed by inserting the second acoustic waveguide 205 into the blood collection tube 21.

According to the above configuration of the liquid level detection mechanism 23, in the liquid level detection of the long blood collection tube 21, as shown in fig. 2 (a), the position of the second acoustic waveguide 205 is increased, and the total length of the extendable acoustic waveguide is shortened. When the liquid level of the blood collection tube 21 is detected in a short length, the second acoustic waveguide 205 is lowered to extend the entire length of the extendable acoustic waveguide as shown in fig. 2 (b). With the above operation, the distance d between the second acoustic waveguide 205 and the blood collection tube 21 can be controlled to a predetermined distance (for example, 2mm to 5mm), and the diffusion of the acoustic wave can be suppressed and the liquid level can be detected with high accuracy for the blood collection tubes 21 having different heights to be transported, that is, the distance from the element unit 202 to the liquid level can be measured. When measuring the liquid surface position in the blood collection tube 21, it is desirable that the ultrasonic distance sensor 200 be disposed coaxially with the first acoustic guide 204 and the second acoustic guide 205, which are telescopic acoustic guides, and the blood collection tube 21 to be measured. Further, it is desirable that the second acoustic waveguide 205 has a shape smaller than the inner diameter of the blood collection tube 21. By making the second acoustic waveguide 205 smaller than the inner diameter of the blood collection tube 21, reflection of acoustic waves from the edge of the blood collection tube 21 can be suppressed.

Fig. 2 (c) is a schematic diagram showing a state of liquid level detection by the conventional ultrasonic distance sensor 200 having no acoustic wave guide. The drawing shows an example of detecting the liquid level of the blood collection tube at the center when three blood collection tubes 21 having different heights are arranged in the carrier rack 22. When the ultrasonic wave is transmitted downward from the upper ultrasonic distance sensor 200, the sound wave shown by the dotted line is diffused, and when the diffused sound wave hits something, the sound wave is reflected. The reflected waves are detected by the ultrasonic distance sensor 200, and signals corresponding to the respective reflected waves are generated. In addition to the illustrated example, the acoustic wave is reflected from the edge of the carriage 22 or the other blood collection tube 21.

In the conventional ultrasonic distance sensor having no acoustic wave guide, as described above, the ultrasonic distance sensor is provided with a dead zone where the reflected wave is not viewed. For example, as indicated by an arrow in fig. 2 (c), a time period during which the reflected wave returns from the top surface of the highest blood collection tube 21 to the space of the ultrasonic distance sensor 200 is set as a dead zone. In this case, when the liquid level of the blood collection tubes 21 positioned on the left and right sides is higher than the liquid level of the blood collection tube at the center of the measurement target, the reflection of the acoustic wave returns from this position. The sound wave also returns from the edge of the blood collection tube.

Fig. 3 is a schematic diagram showing an example of a signal waveform obtained from an ultrasonic distance sensor, fig. 3 (a) shows a signal waveform obtained from an ultrasonic distance sensor of a conventional liquid surface detection device without a sound wave guide, and fig. 3 (b) shows a signal waveform obtained from an ultrasonic distance sensor of a liquid surface detection mechanism with a sound wave guide that is extensible and contractible according to this embodiment.

In the liquid level detection device of the conventional system shown in fig. 2 (c), since ultrasonic waves are propagated diffusely, they are reflected at various portions in the device and detected by the ultrasonic distance sensor. As a result, as shown in fig. 3 (a), after the ultrasonic wave is transmitted at time t0, the detection signal R based on the reflected wave from the liquid surface of the blood collection tube to be measured is output at time t1, and in addition thereto, the detection signals R1 to R4 based on the plurality of reflected waves are output. For example, R1 is a detection signal based on a reflected wave from the upper edge of the blood collection tube to be measured, R2 is a detection signal based on a reflected wave from the liquid surface of the blood collection tube adjacent to the right, R3 is a detection signal based on a reflected wave from the upper surface of the carrier, and R4 is a detection signal based on a reflected wave from the liquid surface of the blood collection tube adjacent to the left. Even if a time zone corresponding to the distance from the upper surface of the highest blood collection tube 21 to the ultrasonic distance sensor 200 as indicated by the arrow in fig. 2 (c) is set as the dead zone T, the detection signals R2 to R4 based on the reflected waves cannot be removed.

On the other hand, the liquid level detection mechanism of the present embodiment uses the acoustic wave guide to improve the directivity of the acoustic wave, and extends and contracts the acoustic wave guide in accordance with the height of the blood collection tube, thereby guiding the ultrasonic wave from the ultrasonic distance sensor 200 to the position directly above the blood collection tube 21 to be measured or the inside of the blood collection tube to be measured. Therefore, the generation of reflected waves from a position other than the liquid surface to be measured can be avoided as much as possible. As a result, as shown in fig. 3 (b), after the ultrasonic wave is transmitted by applying a voltage to the piezoelectric element at time t0, the reflected wave from the liquid surface is received at time t1 and the detection signal R is output, but the reflected wave which becomes a noise is hardly detected during this period. In this way, even when the reflected wave which is a noise is not detected in the measurement of the liquid surface position of the blood collection tube having a long tube length or in the measurement of the liquid surface position of the blood collection tube having a short tube length, the liquid surface position in the blood collection tube can be measured with high accuracy in either case.

Further, in the case of the liquid surface detection mechanism of the present embodiment, the reflected wave from the liquid surface is not detected during the time period in which the acoustic wave transmitted from the piezoelectric element of the ultrasonic distance sensor 200 passes through the acoustic wave guide. Therefore, as shown in fig. 3 (b), the time zone may be set as the dead zone T. Even when the length of the acoustic wave guide is changed by extending and contracting the acoustic wave guide, the dead zone may be switched correspondingly.

In this way, in the measurement of the liquid surface position of the blood collection tube 21 handled by the automatic blood analyzer 10, there are a plurality of blood collection tubes 21 close to each other, and the range of the liquid surface position is large, and it is difficult to set a dead zone. Therefore, a structure for physically shielding sound waves between blood collection tube 21 and ultrasonic distance sensor 200 is effective.

Next, a second embodiment of the liquid level detection mechanism will be explained. In this embodiment, a plurality of acoustic wave guides having different lengths are prepared in advance as the acoustic wave guide. Then, an appropriate acoustic wave guide is selected by the acoustic wave guide replacing mechanism from among a plurality of acoustic wave guides having different lengths according to the height of the blood collection tube being transported, and the acoustic wave guide replacing mechanism is disposed between the blood collection tube and the ultrasonic distance sensor.

As an example, a robot mechanism can be used as the acoustic wave guide replacing mechanism. In this case, a plurality of acoustic wave guides having different lengths are stored in advance in an acoustic wave guide storage unit provided in the liquid level detection mechanism 23, and an appropriate acoustic wave guide is grasped and taken out by the robot mechanism. The robot mechanism disposes the taken-out acoustic wave guide between the blood collection tube and the ultrasonic distance sensor, and measures the liquid level position in the blood collection tube by the ultrasonic distance sensor in this state. Next, when the blood collection tubes at the measurement liquid surface positions are at the same height, the same acoustic wave guide is used as it is, and when the heights are different, the robot mechanism returns the used acoustic wave guide to the acoustic wave guide storage section, and then grips the appropriate acoustic wave guide and places it between the blood collection tubes and the ultrasonic distance sensor to perform measurement. As another example of the acoustic wave guide replacing mechanism, a rotary replacement type acoustic wave guide having a rotary disk can be used. In this case, a plurality of acoustic wave guides having different lengths are fixed in advance around the rotating disk, and the rotating disk is rotated according to the height of the transported blood collection tube, whereby a desired acoustic wave guide is selectively disposed between the blood collection tube and the ultrasonic distance sensor.

Fig. 4 is a schematic diagram showing an example of a liquid level detection mechanism using a rotary replacement type acoustic wave guide. Fig. 4 (a) is a schematic side view and fig. 4 (b) is a schematic top view of the carrier rack as viewed in the traveling direction. In fig. 4 (b), the ultrasonic distance sensor and the base are not shown. If the acoustic wave guide replacing mechanism is constituted by a rotating circular plate, the mechanism system is simpler, and low cost, space saving, and high reliability can be achieved, as compared with the case where the acoustic wave guide replacing mechanism is constituted by a robot mechanism.

The ultrasonic distance sensor 200 and the base 206 have the same configuration as in embodiment 1, and the ultrasonic distance sensor 200 is fixed to the base 206. The configuration of the acoustic wave guide 301 provided between the blood collection tube 21 and the ultrasonic distance sensor 200 in the present embodiment is different from that in embodiment 1. In the example of fig. 4, a plurality of acoustic wave guides 301 having different heights are fixed around a rotating circular plate 302. The acoustic wave guides 301 having different heights are arranged in order of height. The rotating disk 302 is supported by a rotating shaft 303 extending from below, and the rotating shaft 303 is connected to a rotating actuator 304. With the above configuration, the rotating disk 302 including the plurality of acoustic wave guides 301 can be rotated by the operation of the rotary actuator 304. In the liquid level detection mechanism 23 of the present configuration, a gap d1 is provided between the ultrasonic distance sensor 200 and the acoustic wave guide 301, and a gap d2 is provided between the acoustic wave guide 301 and the blood collection tube 21. The clearance d1 and the clearance d2 are each desirably small values, and desirably 5mm or less. Due to the gap d1 and the gap d2, even when the acoustic wave guide 301 is rotated by driving the rotary actuator 304, it can be rotated without contacting the ultrasonic distance sensor 200 and the blood collection tube 21.

In the liquid level detection mechanism 23 of the present embodiment, the liquid level position is measured by rotating the rotating disk 302 according to the height of the conveyed blood collection tube 21 and switching the acoustic wave guide 301 disposed between the ultrasonic distance sensor 200 and the blood collection tube 21. By switching the acoustic wave guide 301, the spread of the acoustic wave generated between the ultrasonic distance sensor 200 and the blood collection tube 21 is suppressed. Therefore, it is necessary to switch the blood collection tubes 21 having different heights to be transported to the acoustic wave guide 301 suitable for the distance between the ultrasonic distance sensor 200 and the blood collection tube 21. As described above, the clearance d2 between the blood collection tube 21 and the acoustic wave guide 301 is preferably 5mm or less. Therefore, it is necessary to prepare and determine in advance the type of the acoustic wave guide 301 having different lengths according to the type of the blood collection tube 31 used in the automatic blood analysis device 10. Further, in order to avoid contact with the rotational movement of the acoustic wave guide 301, the distance L between the blood collection tubes 21 adjacent to each other on the carrier 22 is a distance that does not come within the rotational radius of the acoustic wave guide 301. That is, when the acoustic wave guide 301 is replaced according to the height of the blood collection tube, an interval is required so that the rotating disk to which the acoustic wave guide is fixed can freely rotate.

According to the liquid level detection mechanism of the present embodiment, the acoustic wave guide 301 having a length that can fill the space is switched and arranged between the ultrasonic distance sensor 200 and the blood collection tube 21 according to the blood collection tube 21 having different heights. This suppresses the spread of the acoustic wave between the ultrasonic distance sensor 200 and the blood collection tube 21, and can measure the liquid surface position in the blood collection tube 21 with high accuracy without generating a reflected wave that becomes noise. The second embodiment can be realized by a simple structure capable of directly transmitting the drive of the rotary actuator 304, as compared with the first embodiment. Further, since only the acoustic wave guide 301 is fixed and the movable portion of the acoustic wave guide does not contact the ultrasonic distance sensor while the ultrasonic distance sensor 200 is moving, it is possible to reduce the influence of a positioning error and vibration noise caused by the position adjustment.

Fig. 5 is a schematic diagram showing a third embodiment of the liquid level detection mechanism. This embodiment is a configuration example of a liquid level detection mechanism using a sensor outer periphery up-down type acoustic wave guide. The ultrasonic distance sensor 400 of the liquid surface detection mechanism 23 of the present embodiment has a shape different from that of the ultrasonic distance sensor 200 of embodiments 1 and 2. The signal processing unit 401 is disposed at a position away from the element unit 402, and the element unit 402 and the cylindrical unit 403 each have an elongated cylindrical shape and have a diameter smaller than that of the acoustic wave guide 404. The acoustic wave guide 404 has a cylindrical shape, has an inner diameter larger than the outer diameter of the ultrasonic distance sensor, and is vertically movable by the vertical mechanism 207 so as to surround the ultrasonic distance sensor, similarly to the structure shown in fig. 2.

In the liquid level detection mechanism 23 of the present embodiment, the acoustic wave guide 404 can be moved up and down without contacting the ultrasonic distance sensor 400. Therefore, the acoustic wave guide 404 can be moved up and down according to the height of the blood collection tube 21, and the gap d between the ultrasonic distance sensor 400 and the blood collection tube 21 can be adjusted to 5mm or less. Therefore, when the liquid surface in the blood collection tube 21 is detected, the spread of the sound wave from the ultrasonic distance sensor 400 can be suppressed, and the liquid surface position can be measured with high accuracy. In addition to this, in the present embodiment, the same effects as those of the other embodiments described above can be obtained.

Here, the signal processing unit 401 may be cylindrical and may be disposed so as to be directly connected to the element unit 402. The cylindrical portion 403 is provided to secure a movable region of the acoustic wave guide 404, but the cylindrical portion 403 may not be necessary if the movable region of the acoustic wave guide 404 can be secured by increasing the length of the element portion 402 or providing a cylindrical coupling portion between the element portion 402 and the base 206. That is, even when the acoustic wave guide 404 is moved upward when the long blood collection tube 21 is conveyed, the acoustic wave guide 404 may be formed to have a length not contacting the base 206 or the like, and the length of the element portion 402 or the sum of the element portion 402 and the cylindrical portion 403 becomes the movable region of the acoustic wave guide 404.

Fig. 6 is a schematic diagram showing a configuration example of the liquid level detection system. The control unit of the automatic blood analyzer 10 has a GUI501 for receiving an operation from a user. The blood collection tube data 502 stores the height information of the blood collection tube 21 registered by the user and the height information of the standard blood collection tube 21. The portion where the blood collection tube data 502 is stored is a storage unit in which height information of the blood collection tube is registered in advance. In addition, in the blood collection tube data 502, the barcode ID attached to the blood collection tube 21 is associated with the height information (which may include information on the outer diameter and the inner diameter) of the blood collection tube 21. Therefore, the user selects the type (height) of the blood collection tube 21 for each barcode ID using the GUI 501. Alternatively, information or the like is transmitted from a host terminal or the like that manages the examination in the examination room, and the barcode ID and the information of the blood collection tube 21 are associated in advance. The carrying line 19 of the automatic blood analyzer 10 includes a barcode reader 30 that reads a barcode 29 attached to the blood collection tube 21, and the barcode ID read from the blood collection tube 21 flowing through the carrying line 19 is compared with the pre-registered blood collection tube data 502, whereby the height information of the blood collection tube 21 can be confirmed.

The liquid level detection means 503 checks the height information of the conveyed blood collection tube 21 from the blood collection tube data 502, and controls the acoustic wave guide (any one of 205, 301, and 404) by the acoustic wave guide control unit 504 so as to fill the gap between the blood collection tube 21 and the ultrasonic distance sensor (200 or 400). When the blood collection tube to be measured is positioned below the ultrasonic distance sensor, the sound wave guide control unit 504 controls the sound wave guide, for example, expands and contracts the sound wave guide in the case of an expandable sound wave guide, switches the sound wave guide by rotating a rotating disk in the case of a rotary replaceable sound wave guide, and moves the sound wave guide up and down in the case of a sensor outer periphery up and down type sound wave guide. After at least the distance between the acoustic wave guide and the blood collection tube is equal to or less than a certain value by the control of the acoustic wave guide, the distance measurement unit 505 measures the time during which the acoustic wave transmitted from the ultrasonic distance sensor is reflected from the liquid surface, and measures the liquid surface position in the blood collection tube 21. The measured liquid surface position information is stored in the liquid surface position data 506 and used for controlling the sample dispensing mechanism 15. The process of switching the dead zone T of the ultrasonic distance sensor according to the length of the acoustic wave guide described in fig. 3 (b) can be executed by a program installed in the liquid level detection means 503, for example.

In the present embodiment, before the liquid surface position of the blood collection tube 21 mounted on the carrier 22 flowing on the carrier line 19 is measured, the height information of the blood collection tube 21 is checked, and the driving control of the acoustic wave guide is performed. Here, an example of performing measurement for each blood collection tube 21 is shown, but a plurality of tubes may be simultaneously measured. For example, when five blood collection tubes are mounted on the carrier 22, a plurality of ultrasonic distance sensors and acoustic wave guides may be arranged. In this case, the acoustic wave guides are driven and controlled by the acoustic wave guide control unit 504 in accordance with the heights of the blood collection tubes 21 to be targeted. In addition, the height of the blood collection tube 21 mounted on one carrier rack 22 is restricted in operation, and the control of the acoustic wave guide can be simplified by mounting only the blood collection tube 21 having the same height on one carrier rack 22. In this case, the acoustic wave guides are controlled not by the respective blood collection tube units but by the transport rack unit, and therefore the transport time can be shortened.

Fig. 7 is a schematic diagram showing a configuration example of a liquid level detection system in which a control unit of a dispensing mechanism and inclination determination of a blood collection tube are added. The user can register various data (not only height, but also shape information such as inner diameter, outer diameter, and thickness of the edge) of the blood collection tube 21 in the blood collection tube data 602 from the GUI601, and can register standard shape data of the blood collection tube in the blood collection tube data 602 in advance. Similarly to the liquid level detection system of fig. 6, the barcode ID attached to the blood collection tube 21 is also associated with the data of the blood collection tube 21 by the blood collection tube data 602.

In the liquid level detection system shown in fig. 7, not only the liquid level position of the blood collection tube 21 but also the inclination of the blood collection tube 21 can be measured. The position measuring unit 603 instructs the acoustic wave guide control unit 604 and the distance measuring unit 605 to control the acoustic wave guide (any one of 205, 301, and 404) and the ultrasonic distance sensor (200 or 400). The position measuring unit 603 recognizes the position of the carrier 22 carried by the carrying line 19, and drives and controls the acoustic wave guide so that the gap between the ultrasonic distance sensor and the blood collection tube is reduced as described above when measuring the liquid surface position in the blood collection tube 21. The position measuring unit 603 measures the height of the edge of the blood collection tube 21 and the height of the upper surface of the carrier 22. For example, at a timing when the edge of the blood collection tube 21 moves below the ultrasonic distance sensor 200, the control of raising or rotating the acoustic wave guide is performed so that the edge of the blood collection tube 21 can be recognized by the ultrasonic distance sensor 200. Similarly, the control for lowering the acoustic wave guide is performed at the timing when the upper surface portion of the carrier 22 moves below the ultrasonic distance sensor. Further, since the upper surface of the carrier 22 has a large area, detection can be performed even in a state where there is no acoustic wave guide. As described above, in the liquid level detection system shown in fig. 7, the liquid level in the blood collection tube 21, the height of the upper edge of the blood collection tube 21, and the position of the upper surface of the carrier 22 can be measured.

The position measuring unit 603 can identify the position of the carrier 22 on the transport line 19 by controlling the transport line 19 itself or by communicating with a control unit that controls the transport line 19. Further, it is desirable to increase control for switching the dead band (unmeasured region) of the ultrasonic distance sensor in accordance with the length of the acoustic wave guide. The height information of the edge of the blood collection tube 21 measured by the above-described method is at least two points, for example, the height information of both ends of each blood collection tube 21 in the traveling direction in fig. 7.

The position data 606 records information on the measured liquid surface position in the blood collection tube 21, the height of the edge of the blood collection tube 21, and the height of the carrier rack 22.

After measurement by the ultrasonic distance sensor (200 or 400), the transport rack 22 transports the sample dispensing mechanism 15 to a position where sample dispensing is performed during a transport operation by the transport line 19. At the sample dispensing position, as described above, the nozzle 25 of the sample dispensing mechanism 15 is stopped at the liquid surface suction position in the blood collection tube 21. That is, in order to suck the liquid, the tip is stopped at a position lower than the liquid surface by several millimeters. At this time, since the liquid surface position is already measured by the liquid surface detection means using the ultrasonic distance sensor and recorded in the position data 606, the deceleration in the lowering operation of the nozzle 25 can be performed at any timing. The position of the sample dispensing mechanism 15 is controlled by the dispensing control unit 607. For example, since the nozzle 25 of the sample dispensing mechanism 15 vibrates at the natural frequency of the mechanism when it is lowered, the dispensing control unit 607 can adjust the operation parameters such as the deceleration time and the deceleration timing so as to cancel out the vibration of the sample dispensing mechanism 15. The adjustment of the operation parameters can be performed before or during the lowering operation of the nozzle 25 by a control program installed in the dispensing control unit 607, for example. As described above, the nozzle 25 of the sample dispensing mechanism 15 includes the contact capacitance type sensor, and the liquid surface contact confirmation unit 608 can confirm that the liquid has contacted.

However, if the blood collection tube 21 is inclined, the liquid surface contact confirmation unit 608 may generate erroneous detection. The reason for the erroneous detection is that the nozzle 25 is close to the electrostatically charged blood collection tube 21, and if the inclination of the blood collection tube 21 is known, the erroneous detection can be avoided. Therefore, the liquid level detection system of the present embodiment includes the inclination determination unit 609 of the blood collection tube. The inclination determination unit 609 reads the height information of the upper edge of the blood collection tube 21 at two or more points from the position data 606, and determines the inclination of the blood collection tube. In the determination of the inclination, the following three kinds of determinations are performed based on the height information of two points (desirably, both ends) on the upper edge of the blood collection tube.

(a) Normal (the heights of the two points are the same and normal value)

(b) Inclined with respect to the traveling direction of the conveyance line 19 (height difference between two points)

(c) Inclined in the left-right direction with respect to the conveyance line 19 (the heights of both points are higher than a normal value).

In both the determinations (a) and (c), the heights of the two points are compared with the height from the upper surface of the rack. When the height from the upper surface of the rack between the two points is a predetermined value, the height is determined to be a normal value.

In addition to the above determination method, the inclination may be determined based on multipoint measurement data by performing contour tracing. Further, it is also possible to use information on the position of the upper surface of the carrier 22 to increase whether or not the blood collection tube 21 is not higher than the normal position, that is, in a non-floating state.

Using the above-described inclination determination unit 609 of the blood collection tube 21, it is possible to increase the control for avoiding erroneous detection by the liquid level detection correction unit 610 during the lowering operation of the nozzle 25 that contacts the detection liquid level. The processing contents of the liquid level detection correction unit 610 will be described below.

In the liquid level detection system having the above configuration, first, the liquid level position of the blood collection tube 21 conveyed by the conveying line 19 is measured by the liquid level detection mechanism 23 using an ultrasonic distance sensor. Next, when the blood collection tube 21 is conveyed to the sample dispensing mechanism 15, an operation for optimizing the lowering operation of the nozzle 25, that is, an operation mode capable of suppressing vibration is performed. Contact with the liquid is confirmed by the liquid surface contact confirming section 608, and reliable and accurate suction of the liquid is realized. The liquid level detection function can be used without the tilt determination unit 609 and the liquid level detection correction unit 610. By adding the tilt determination unit 609 and the liquid level detection correction unit 610, erroneous detection by the contact type liquid level detection mechanism can be reduced, and a system with higher reliability can be realized.

If the result (position data 606) measured by the liquid surface detection means using the ultrasonic distance sensor does not match the result (the amount of lowering of the nozzle 25) confirmed by the contact type liquid surface contact confirmation unit 608, the detection data of either one is erroneous, but the risk of erroneous detection by the contact type liquid surface contact confirmation unit can be confirmed or recorded by using the inclination determination unit 609.

Fig. 8 is a diagram showing an example of the processing flow of the liquid level detection system. Here, an example of a method of correcting the operation of the sample dispensing mechanism 15 and a method of lowering the arm using the inclination determination unit 609 will be described. As described above, the blood collection tube 21 may be inclined with respect to the carrier 22. When the nozzle 25 is lowered toward the blood collection tube 21 in such a state, not only the erroneous detection due to the contact-type liquid level detection but also the edge and the side surface of the blood collection tube 21 may come into contact with the nozzle 25. Therefore, in the control of the sample dispensing mechanism 15 according to the present embodiment, the inclination determination unit 609 is used to avoid the contact of the nozzle 25 with the blood collection tube 21.

Fig. 8 (a) is a diagram showing an example of a control flow when the sample dispensing mechanism 15 horizontally moves the arm to aspirate a sample from the blood collection tube 21. As described above, the sample dispensing mechanism 15 positions the nozzle 25 between the reaction cell 26 of the reaction disk 13 and the suction position of the blood collection tube 21 by the rotation operation of the arm. However, when the blood collection tube 21 is largely inclined, the nozzle 25 which is lowered may contact the blood collection tube 21. The sample dispensing mechanism 15 has a sensor (switch) for detecting abnormal contact of the nozzle 25, and stops the apparatus when abnormal contact is made. Therefore, it is desirable to avoid the risk of contact as much as possible.

The control flow of the sample dispensing mechanism 15 according to the present embodiment includes a process of determining whether or not the blood sampling tube is tilted by the tilt determination unit 609 (S701). If there is a tilt, the process proceeds to a process of determining the risk of contact between nozzle 25 and cartridge 21 (S702), and the diameter of the opening of cartridge 21 is read from cartridge data 602, and the measured liquid level is read from position data 606, and it is determined whether or not the distance closest to cartridge 21 during the lowering operation of nozzle 25 is equal to or less than a preset value. Since the nozzle 25 is elongated and easily vibrated, it is desirable that the nozzle be separated from the wall of the blood collection tube 21 by at least several millimeters. The process of determining the contact risk can be executed by a program installed in the inclination determination unit 609, for example. When it is determined that there is a risk of contact, the arm rotation operation (S704) is performed after adding a correction value to the horizontal movement amount of the nozzle by the arm rotation operation (S703), so that contact with the blood collection tube 21 can be avoided. The processing of adding the correction value to the horizontal movement amount of the nozzle can be executed by, for example, a dispensing control program installed in the dispensing control unit 607.

Fig. 9 is a schematic diagram showing a state of correction of the horizontal movement amount of the nozzle. In this example, the blood collection tube 21 is inclined, and it is determined that the nozzle 25 may come into contact with the blood collection tube as indicated by a broken line in a normal rotation operation of the arm. Therefore, by adding correction indicated by an arrow to the horizontal movement amount of the nozzle obtained by the normal arm rotation operation and moving the nozzle 25 to the solid line position, the nozzle 25 is lowered into the blood collection tube 21 without contacting the blood collection tube 21, and the sample is sucked. In the above processing, the normal arm rotation is performed without tilting the blood collection tube 21. In addition, after it is determined that there is a contact risk in the determination (S702) of whether there is a contact risk, the operation may be stopped by an alarm without adding a correction value.

Here, although an example in which the nozzle 25 is horizontally moved by rotation of the arm to which the nozzle is fixed has been described, depending on the configuration of the dispensing mechanism, the nozzle may be horizontally moved by combining rotation of the arm and extension and contraction of the arm. Alternatively, a driving method may be used in which the nozzle is horizontally moved to an arbitrary position by two linear mechanisms linearly moved in mutually orthogonal directions.

Fig. 8 (b) is a diagram showing an example of the control flow of the arm lowering operation. When the inclination of the blood collection tube 21 is confirmed by the inclination determination unit 609 (S711) and there is an inclination, the position where the nozzle 25 approaches the blood collection tube 21 is set as the insensitive area of the sensor (S712). Fig. 10 is a schematic diagram showing an example of the output and the insensitive area setting of the electrostatic capacity sensor. In the figure, the dotted line indicates the output waveform of the capacitance sensor when the blood collection tube is not tilted, and the solid line indicates the output waveform of the capacitance sensor when the blood collection tube is tilted. When the blood collection tube is tilted, as shown in fig. 9, when the nozzle 25 of the sample dispensing mechanism 15 is lowered, the output of the capacitance sensor exceeds the liquid level detection threshold SH and causes erroneous detection, because the output does not pass through the center of the upper opening of the blood collection tube but approaches one edge. Therefore, as shown in fig. 10, the time zone in which the nozzle 25 approaches the upper edge of the blood collection tube is set to the dead zone T1. The setting of the dead zone T1 can be executed by, for example, a liquid level detection correction program installed in the liquid level detection correction unit 610. With this setting, the electrostatic capacitance that changes when the nozzle 25 approaches the blood collection tube 21 is disregarded. Since the liquid surface position is stored in the position data 606, all the upper region of several millimeters from the liquid surface position may be set as the insensitive region T2.

After the above dead zone is set, the arm lowering start process is performed (S713), and the electrostatic capacitance is changed by the approach of the nozzle 25 to the liquid surface. Contact with the liquid surface is detected based on a determination that the change in the capacitance is equal to or greater than a threshold value (S714), and when contact with the liquid is detected during the determination, arm lowering is stopped (S715). By performing the above operation, even when the liquid surface position in the position data 606 includes erroneous information, the nozzle 25 can be reliably stopped. Further, the liquid surface position data of the position data 606 may be compared with the position where the change in capacitance exceeds the threshold value (S716), and error processing may be performed if a mismatch occurs. In this case, there is an error in the liquid surface position measured by the liquid surface detection mechanism 23 using the ultrasonic distance sensor or the liquid surface position detected by the contact-type liquid surface contact confirmation portion 608 using the capacitance-type sensor. As described above, the inclination information of the blood collection tube 21 may be recorded, or a message indicating that the user has corrected the inclination of a certain value or more may be displayed on a GUI or the like.

In the present embodiment, an example of measuring each blood collection tube is shown, but the liquid level of a plurality of blood collection tubes may be measured simultaneously by arranging a plurality of the above-described acoustic wave guides and ultrasonic distance sensors. In the present embodiment, sample dispensing by an automatic blood analyzer is described as an example, but the liquid level detection mechanism of the present invention can be similarly applied to other dispensing nozzles such as a reagent container and a reagent dispensing nozzle.

The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail to explain the present invention easily and understandably, and are not limited to having all the configurations described. In addition, a part of the structure of one embodiment may be replaced with the structure of another embodiment, and the structure of another embodiment may be added to the structure of one embodiment. Further, addition, deletion, and replacement of another configuration can be performed on a part of the configurations of the embodiments.

Further, the above-described respective structures, functions, processing units, processing means, and the like may be realized by hardware by designing a part, all, or the like of the above-described integrated circuit, for example. The above-described respective structures, functions, and the like may be realized by software by interpreting and executing a program for realizing the respective functions by a processor. Information such as programs, tables, and files for realizing the respective functions can be stored in a memory, a hard disk, a recording device such as an ssd (solid State drive), or a recording medium such as an IC card, an SD card, or a DVD.

Description of the symbols

11-reagent container, 12-reagent disk, 13-reaction disk, 14-reagent dispensing mechanism, 15-sample dispensing mechanism, 21-blood collection tube, 22-transport rack, 23-liquid level detection mechanism, 25-nozzle, 200-ultrasonic distance sensor, 204-first acoustic wave guide, 205-second acoustic wave guide, 206-base, 207-up-down mechanism, 301-acoustic wave guide, 302-rotating disk, 303-rotating shaft, 304-rotating actuator, 400-ultrasonic distance sensor, 404-acoustic wave guide.