Automatic analysis device and analysis method for automatic analysis device

Abstract

An automatic analysis device that uses a tube pump as a reagent supply mechanism and maintains low cost and constant discharge accuracy, and an analysis method for the automatic analysis device according to the present invention have the following configuration.　An automatic analysis device comprising: a storage unit that stores, for each liquid transfer amount, the relationship between the residual amount of a liquid in a container and the number of rotational drive steps of a stepping motor for rotationally driving the tube pump so that there is a prescribed amount of the liquid in the container; a determination unit that determines the liquid transfer amount to be transferred to the container in the next analysis cycle on the basis of the residual amount of the liquid used in the previous analysis cycle in the container as measured by a measurement mechanism; and a control unit that controls the rotational drive of the stepping motor to transfer the liquid to be used in the next analysis cycle to the container on the basis of the liquid transfer amount to be transferred to the container as determined by the determination unit, and the relationship between the residual amount of the liquid in the container and the number of rotational drive steps of the stepping motor for rotationally driving the tube pump.

Description

Automated analyzer and analysis method for the automated analyzer

[0001] The present invention relates to an automatic analyzer and an analysis method for the automatic analyzer.

[0002] Simple and inexpensive tube pumps are known as reagent supply means for automated analyzers. A tube pump, also known as a peristaltic pump or a peristaltic pump, compresses a tube with a roller and moves the roller to squeeze the tube, thereby pumping the liquid inside the tube. After the roller moves, the compressed tube returns to its original shape due to its restoring force, generating negative pressure within the tube, which then draws the liquid. By repeatedly performing this operation, the liquid is sequentially pumped (see Patent Document 1).

[0003] Japanese Patent Application Publication No. 9-297122

[0004] While tube pumps are less expensive and require less space than syringe pumps, they have the characteristic of lower discharge accuracy than standard syringe pumps due to the mechanism of squeezing the liquid with rollers, which is prone to pulsation, air bubbles, individual differences in the tubing, and deformation of the tubing over time. To maintain discharge accuracy, the rotation speed and amount of the rollers must be set appropriately. For example, if the rotation speed of the rollers is lower than the ideal range, the flow may become pulsating rather than steady, resulting in an unstable flow rate. On the other hand, if the rotation speed is too high, it may promote wear and deformation of the tubing, compromising long-term stability.

[0005] An object of the present invention is to provide an automatic analyzer that uses a tube pump as a reagent supply mechanism, is low cost, and maintains a constant discharge accuracy, and an analysis method for the automatic analyzer.

[0006] The present invention achieves the above object by providing an automatic analyzer and an analytical method for the automatic analyzer, the automatic analyzer comprising: a measuring mechanism for measuring the amount of liquid remaining in a container that stores the liquid to be used in analyzing a sample; a tube pump for transferring the liquid to the container; and a stepping motor for rotating the tube pump at a predetermined steady rotation speed, the automatic analyzer comprising: a memory unit for storing, for each amount of liquid transferred, a relationship between the amount of liquid remaining in the container and the number of rotational drive steps of the stepping motor for rotating the tube pump so that the liquid in the container reaches a predetermined amount; a determination unit for determining the amount of liquid to be transferred to the container in the next analysis cycle based on the amount of liquid remaining in the container used in the previous analysis cycle measured by the measuring mechanism; and a control unit for controlling the rotational drive of the stepping motor to transfer the liquid to be used in the next analysis cycle to the container based on the relationship between the amount of liquid to be transferred to the container determined by the determination unit, the amount of liquid remaining in the container stored in the memory unit, and the number of rotational drive steps of the stepping motor for rotating the tube pump so that the liquid in the container reaches the predetermined amount.

[0007] According to the present invention, it is possible to provide an automatic analyzer that uses a tube pump as a reagent supply mechanism, and that maintains a certain level of discharge accuracy at low cost, and an analysis method for the automatic analyzer.

[0008] Schematic diagram showing the configuration of an automatic analyzer. Schematic diagram showing an example of the configuration of a reservoir mechanism and its surroundings in an automatic analyzer. A diagram showing an example of the configuration of a control device related to the process of determining the supply of the first liquid and the second liquid. A flowchart showing an example of a method for determining the type of liquid and analysis cycle, calculation formula, specified range, and liquid supply amount in the liquid supply. A graph showing an example of the transition of the actual number of steps in the supply of the first liquid and the second liquid.

[0009] The following description of the preferred embodiments of the present invention will be made with reference to the accompanying drawings. In each drawing, common or similar components are designated by the same reference numerals, and redundant descriptions thereof will be omitted. It goes without saying that, in the following embodiments, the components (including element steps, etc.) are not necessarily essential unless otherwise specified or considered to be clearly essential in principle.

[0010] First, the main components of the automated analyzer will be described. Fig. 1 is a top view of the schematic configuration of the automated analyzer 101. The automated analyzer 101 includes a reservoir mechanism 102, a first liquid bottle 103, a second liquid bottle 104, a detergent bottle 105, a pure water bottle 106, a waste liquid bottle 107, a first liquid feed pump (tube pump) 108, a second liquid feed pump (tube pump) 109, an incubator (reaction disk) 110, a dispensing unit 111, sample containers 112 for containing samples, a sample holder (sample disk) 113 for holding the sample containers 112, reagent containers 114 for containing reagents, a reagent holder (reagent disk) 115 for holding the reagent containers 114, a sample disk 113, a sample / reagent shared disk 116 having the reagent disk 115, a transport unit 117, a storage unit 118, and a control device 119 for controlling the overall operation of the automated analyzer 101. The reservoir mechanism 102 has an analysis section 120 at its upper part. The storage section 118 has a structure including a first liquid storage section 121 and a second liquid storage section 122 at its front and rear (details will be described later using FIG. 2).

[0011] The incubator 110 has a reaction vessel holding unit 124 that holds a plurality of reaction vessels 123 for reacting a sample with a reagent. The reaction vessel holding unit 124 is a plurality of holes provided on a disk for holding the reaction vessels 123. The dispensing unit 111 dispenses the sample from the sample vessel 112 into the reaction vessels 123 accommodated in the incubator 110 using a drive mechanism such as a rotation drive mechanism or a vertical drive mechanism. Similarly, the dispensing unit 111 dispenses the reagent from the reagent vessel 114 into the reaction vessels 123 accommodated in the incubator 110 using a drive mechanism (not shown) such as a rotation drive mechanism or a vertical drive mechanism.

[0012] The transport unit 117 moves the reaction vessel 123 containing the reaction solution that has been reacted for a predetermined time in the incubator 110 to the reservoir mechanism 102. The analysis unit 120 is a detection mechanism for immunoassays, and includes, for example, a photomultiplier tube, a light source lamp, a spectroscope, a photodiode, etc. (all of which are not shown). It also has a function for adjusting the temperature of these detection mechanisms. The analysis unit 120 performs optical measurements of the reaction solution in the reaction vessel 123 during immunoassays. Methods for detecting labeled substances in immunoassays include those that use electrochemiluminescence and chemiluminescence. The structures and physical properties of the first liquid, labeled substance, and detection region are selected depending on the method. The analysis unit 120 measures the amount of luminescence resulting from the luminescence reaction of the labeled substance using a photomultiplier tube as a detector.

[0013] The control device 119 includes a control unit 125, a memory unit 126, a calculation unit 127, an operation unit 128, and a display unit 129. The control device 119 controls various processes related to the automated analyzer 101, such as processes related to dispensing samples and reagents, processes such as temperature management in the incubator 110, processes related to the reservoir mechanism 102, and processes related to maintenance of the first liquid feed pump 108 and the second liquid feed pump 109. The control device 119 is composed of a processor and the like, and performs these processes by executing control programs read from the memory unit 126. The memory unit 126 has a non-volatile memory and stores the operating program and setting information of the automated analyzer 101, calculation results by the control unit 125, and the like. The memory unit 126 also stores determination conditions related to maintenance of the first liquid feed pump 108 and the second liquid feed pump 109, and the like. The control unit 125 is configured to be able to communicate with the analysis unit 120.

[0014] FIG. 2 is a schematic diagram showing an example of the reservoir mechanism 102, analysis unit 120, and their peripheral configuration of an automated analyzer. The reservoir mechanism 102 includes a liquid level detection sensor (hereinafter, referred to as sensor) 201, an aspiration nozzle 202, a reservoir 118 to which liquid is to be delivered, an operation stage (mounting unit) 203, and an operation mechanism 204. The reservoir 118 has a first liquid reservoir 121 for storing a first liquid at the front side in FIG. 1 and a second liquid reservoir 122 for storing a second liquid at the back side. The first liquid bottle 103 is filled with a first liquid for detecting components contained in a sample, and the second liquid bottle 104 is filled with a second liquid for cleaning. The first liquid delivered from the first liquid bottle 103 by the first liquid delivery pump 108 is supplied to the first liquid reservoir 121 via a first flow path 205 and a second flow path 206. In this embodiment, the term "supply" is used for ease of understanding, but the term "liquid transfer" is used in the claims because the term "supply" may be interpreted in a limited manner. The second liquid transferred from the second liquid bottle 104 by the second liquid transfer pump 109 is supplied to the second liquid storage portion 122 via the third flow path 207 and the fourth flow path 208.

[0015] While a dispensing pump (not shown) connected to the dispensing unit 111 is required to have high dispensing accuracy, the first liquid feed pump 108 and second liquid feed pump 109 used for liquid replenishment do not require such high accuracy. For this reason, tube pumps that are inexpensive and easy to maintain are used for the first liquid feed pump 108 and second liquid feed pump 109.

[0016] A tube pump is a pump that pumps liquid inside a tube by squeezing the tube with rollers and driving the rollers to squeeze the tube. A tube pump has multiple rollers on the outer periphery of the rotating part, and is designed so that the tube can be made to crawl over the rollers and come into contact with them, crushing the tube with the rollers. After the multiple rollers are driven by rotation, the crushed tube returns to its original shape due to the tube's restoring force, and at that time negative pressure is generated inside the tube and the liquid is sucked in. By performing this operation continuously, the liquid is pumped sequentially.

[0017] Tube pumps may use a DC motor or a stepping motor. When a DC motor is used, the tube pump is driven by the DC motor, and the number of rotations and rotation speed are controlled by controlling the current through the applied voltage. When a stepping motor is used, the tube pump is driven by the stepping motor, and the number of roller rotations is controlled by the number of steps, and the rotation speed is controlled by the step rate. In this embodiment, a tube pump equipped with a stepping motor will be used for explanation.

[0018] The reservoir 118 to which the liquid is supplied is placed on the operation stage 203. The operation mechanism 204 drives the operation stage 203 and the reservoir 118 in the horizontal and vertical directions of the device by using a vertical drive mechanism.

[0019] The liquid level detection sensor 201 is a sensor that detects the level of the liquid supplied to the storage unit 118. The suction nozzle 202 is a nozzle that suctions and removes the liquid remaining in the storage unit 118. The liquid level detection sensor 201 and the suction nozzle 202 are formed, for example, in a rod shape and are arranged to extend vertically above the storage unit 118. One end of the liquid level detection sensor 201 and the suction nozzle 202 is connected to the analysis unit 120, and the liquid level detection sensor 201 and the suction nozzle 202 are fixed in a state hanging down from the analysis unit 120. The operation mechanism 204 drives the storage unit 118 in the vertical direction together with the operation stage 203, and when the liquid level in the storage unit 118 touches the other end below the liquid level detection sensor 201, the liquid level is detected. The liquid level detection sensor 201 outputs a liquid level detection signal when it detects the liquid level. The output liquid level detection signal is sent from the analysis unit 120 to the control unit 125, and the amount of liquid remaining in the storage unit 118 is calculated from the amount of drive of the operating mechanism 204 until the liquid level is detected.

[0020] The suction nozzle 202 is connected to the pump 210 via a fifth flow path 209. When the pump 210 is driven, the suction nozzle 202 sucks the liquid in the storage portion 118. The liquid sucked by the suction nozzle 202 is sent to the outside of the reservoir mechanism 102 via the fifth flow path 209 and a sixth flow path 211 by driving the pump 210, and is discharged into the waste liquid bottle 107.

[0021] The analysis unit 120 includes a basic circuit related to liquid level detection. In this case, the liquid level detection unit 301 shown in FIG. 3 controls the liquid level detection process. The analysis unit 120 is connected to the control unit 125 shown in FIG. 1 and transmits the liquid level detection results related to the liquid level detection process to the control device 119. Alternatively, the analysis unit 120 may be a functional block that performs processing related to liquid level detection in the storage unit 118. In this case, the analysis unit 120 includes, for example, a processor, a memory, etc. The processor executes a program stored in the memory to perform processing related to liquid level detection.

[0022] In the following description, the first liquid feed pump 108 and the second liquid feed pump 109 may be referred to as a tube pump 212 .

[0023] FIG. 3 is a diagram showing an example of the configuration of the control device 119 and its peripherals related to the process of determining whether to supply the first liquid and the second liquid.

[0024] The memory unit 126 stores the reference supply amount Vi (μl), the reference rotation speed Ri, the reference step number Mi (step), the actual supply amount Vs (μl), the actual rotation speed Rs, the actual step number Ms (step), the remaining liquid amount W (μl), the liquid delivery resolution (μl / step), etc. These are values ​​used in the calculation process of the supply amount of the first liquid and the second liquid and the process of confirming the remaining liquid amount. Here, the reference supply amount Vi is the design value of the amount of reagent consumed per analysis cycle. The reference rotation speed Ri is the value obtained by converting the reference supply amount Vi into the number of roller rotations. The reference step number Mi is the value obtained by converting the reference rotation speed Ri into the number of motor steps. The actual supply amount Vs is the amount of reagent delivered in the next analysis cycle, calculated based on the reference supply amount Vi, the remaining liquid amount W, and the liquid delivery resolution. The actual rotation speed Rs is the value obtained by converting the actual supply amount Vs into the number of roller rotations. The actual step number Ms is the value obtained by converting the actual rotation speed Rs into the number of motor steps. As described above, the formula used to calculate the actual supply volume Vs can be switched depending on the type of reagent and the type of cycle to be executed in the next analysis cycle. Similarly, the specified range used in the process of checking the remaining liquid volume W can be switched depending on the type of reagent and the type of cycle.

[0025] The liquid level detection unit 301 is a functional block that detects the liquid level in the reservoir 118 in cooperation with the liquid level detection sensor 201 , and is provided within the analysis unit 120 .

[0026] The calculation unit 127 includes a drive amount calculation unit 302 for vertically driving the operation mechanism 204, a remaining liquid amount calculation unit 303, a determination unit 304, an actual step number setting unit 305, and the like.

[0027] The drive amount calculation unit 302 is a functional block that calculates the drive amount of the vertical drive of the operating mechanism 204 .

[0028] The remaining liquid amount calculation unit 303 is a functional block that calculates the amounts of the first liquid and the second liquid remaining in the storage unit 118. The determination unit 304 is a functional block that determines whether or not a supply will be made in the next cycle and the amount of the supply, based on the remaining amounts of the first liquid and the second liquid calculated by the remaining liquid amount calculation unit 303.

[0029] The actual step number setting unit 305 is a functional block that sets the number of steps for driving the tube pump 212 based on the supply amount determined by the determining unit 304 .

[0030] FIG. 4 is a flowchart showing an example of a method for determining the type of liquid and analysis cycle, the calculation formula, the designated range, and the liquid supply amount in the first liquid supply.

[0031] In step S101, the liquid level detection unit 301 performs a liquid level detection operation, and the process proceeds to step S102.

[0032] In step S102, the remaining liquid amount calculation unit 303 calculates the remaining liquid amount from the drive amount of the operating mechanism 204 required to raise the liquid level until the liquid level is detected, and the process proceeds to step S103.

[0033] In step S103, it is determined whether the next reaction liquid is present in the reaction vessel 123. If it is determined that a reaction liquid is present (Yes), the first liquid is selected and the process proceeds to step S104. If it is determined that no reaction liquid is present (No), the process proceeds to step S105, where the analysis operation is stopped and terminated.

[0034] In steps S104 and S106, the analysis cycle to be executed is determined. In steps S107 and S108, a calculation formula and a designated range corresponding to the determined analysis cycle are determined, and the process proceeds to step S109. Note that these analysis cycles, calculation formulas, and designated ranges can be freely added by the user.

[0035] In step S109, the determination unit 304 determines the amount of remaining liquid in the storage unit 118. If it is determined that the amount of remaining liquid is below the lower limit of the range determined in step S108, the alarm mechanism outputs (notifies) an abnormality alarm in step S110, and the analysis operation is stopped and terminated in step S111. If it is determined that the amount of remaining liquid is above the upper limit of the range, the process proceeds to step S112. In step S112, the supply operation is skipped. If it is determined that the amount of remaining liquid is within the range, the process proceeds to step S113.

[0036] In step S113, the actual step number setting unit 305 sets the actual step number of the motor in the tube pump 212 during supply based on the remaining liquid amount determined by the determining unit 304, and the process proceeds to step S114.

[0037] In step S114, the next cycle is carried out, and the process proceeds to step S115.

[0038] In step S115, the liquid selected in step S103 is aspirated, and the process proceeds to step S116.

[0039] In step S116, the motor in the tube pump 212 is driven to supply the first liquid based on the actual number of steps set by the actual step number setting unit 305. After the supply, the process proceeds to step S117. Note that the process also proceeds to step S117 after skipping the supply operation in step S112.

[0040] In step S117, the first liquid is used to detect components in the specimen, and then the operations from step S101 onwards are repeated.

[0041] The second liquid is used for cleaning in step S117. The type of liquid and analysis cycle, calculation formula, specified range, and liquid supply amount are determined using a flowchart similar to that shown in Figure 4. Steps S106, S107, and S108 have different analysis cycles, calculation formulas, and specified ranges.

[0042] In this embodiment, the amount of liquid to be supplied in the next analysis cycle is calculated based on the amount of liquid remaining in the reservoir 118 (hereinafter referred to as the remaining amount of liquid).The number of rotations of the roller, i.e., the number of steps for operating the motor, is calculated based on the amount of liquid to be supplied and the liquid delivery resolution (amount of liquid to be supplied per step of the stepping motor).

[0043] Here, the roller rotation speed, i.e., the motor step rate, is constant regardless of the liquid supply amount. The calculation process for the liquid supply amount and the number of motor steps is performed at the end of each analysis cycle. This process makes it possible to supply an amount of reagent equivalent to the amount consumed in the immediately preceding analysis cycle. Furthermore, by maintaining a constant roller rotation speed, disturbance of the liquid surface due to pulsation and wear and deterioration of the tube, which are expected in tube pumps, are reduced, enabling stable reagent supply over the long term.

[0044] Information regarding the remaining amount of liquid is used as an indicator to confirm whether the amount of reagent consumed or supplied is appropriate. For example, if the amount of remaining liquid falls outside (exceeds or falls below) a specified range defined by the device, a malfunction related to the consumption or supply of reagent is suspected, and an abnormality alarm is output and the analysis operation is stopped. In this case, it is not necessary to stop the device. For example, if the amount of remaining liquid exceeds the specified range, i.e., if a sufficient amount of reagent remains in the reservoir 118, the reagent supply process may be omitted in the next analysis cycle. Furthermore, if the amount of remaining liquid falls below the specified range, i.e., if no reagent remains in the reservoir 118, the reagent supply process may be performed multiple times in the next analysis cycle instead of just once.

[0045] Table 1 shows the correspondence between the type of reagent to be supplied, the type of cycle to be executed in the next analysis cycle, the formula used to calculate the amount of reagent to be supplied, and the specified range used in the process of checking the remaining liquid amount.

[0046]

[0047] The liquid supply amount calculation process and remaining liquid amount confirmation process are performed for each of the first and second liquids. The calculation formula used in the supply amount calculation process can be switched depending on the type of reagent (first or second liquid) and the type of cycle to be executed in the next analysis cycle. The specified range used in the remaining liquid amount confirmation process can also be switched depending on the type of reagent and the type of cycle. Note that there may be one or more types of calculation formulas and ranges.

[0048] FIG. 5 shows the relationship between the supply amount (liquid delivery amount) calculated by the formula and the actual number of steps required to rotate the stepping motor. The remaining liquid amount represents the amount of each liquid remaining in the reservoir 118, calculated by the remaining liquid amount calculation unit 303. Here, supply amount (liquid delivery amount) = amount of liquid that should be in the container - amount of remaining liquid. The vertical axis represents the actual number of steps required to supply each liquid, set by the actual step number setting unit 305 based on the amount of remaining liquid. The solid line represents an example of the transition in the actual number of steps for the first liquid (mainly reagent) used in analyzing the sample, and the dotted line represents an example of the transition in the actual number of steps for the second liquid (liquid such as detergent for cleaning the liquid delivery unit, such as the aspiration nozzle 202, the analysis unit, etc.). As can be seen from Figure 5, the relationship between the number of rotational drive steps of the stepping motor required to rotate the tube pump so that the liquid in the reservoir 118 reaches a predetermined amount is expressed by the following linear equation: y = ax + b, where y is the number of rotational drive steps of the stepping motor, x is the amount of liquid remaining in the container, a is a coefficient determined by the specifications of the tube pump, and b is a constant determined by the amount of liquid transferred. The amount of reagent used in sample analysis (corresponding to the first liquid in Figure 5, or "liquid" in the claims) is predetermined for each analysis item. In other words, since the transfer amount is predetermined, Equations 1 to 4 are associated with each analysis item (or each reagent). As the number of reagent types increases, the number of corresponding equations also increases. The second liquid is primarily intended to be a cleaning liquid, and Equations 5 to 8 are also associated with this liquid depending on the amount of liquid transferred.

[0049] The amount of liquid remaining in the storage unit 118 (referred to as a "container" in the claims) to be transferred is measured by a liquid level detection sensor 201 (referred to as a "measurement mechanism" in the claims). The storage volume of liquid in the storage unit 118 when storing the liquid is determined in advance. For example, the line 1 cm below the top of the storage tank is determined as the liquid storage volume. Then, the amount of liquid to be transferred to the liquid storage tank can be calculated from the difference between the liquid level measured by the liquid level detection sensor 201 and the predetermined liquid storage volume when storing the liquid.

[0050] On the other hand, a memory stores a relationship between each liquid transfer amount (transfer amount) and the number of rotational drive steps of the stepping motor for rotating the tube pump so that the liquid in the reservoir 118 reaches a predetermined amount, and a liquid transfer amount that matches the calculated liquid amount to be transferred to the liquid reservoir tank is extracted from the memory, and a determination unit determines the number of rotational drive steps of the stepping motor for rotating the tube pump corresponding to the extracted liquid transfer amount. By rotating the stepping motor by the determined number of rotational drive steps of the stepping motor, the liquid to be used in the next analysis cycle is transferred to the container.

[0051] As mentioned above, tube pumps may not be able to consistently deliver the same amount of liquid each time they are pumped due to factors such as pulsation and the presence of air bubbles. Furthermore, the accuracy of the pumping may change over time due to individual differences in the tubes and the tubes' deformation over time. On the other hand, it is desirable that a predetermined amount of liquid is contained in the reservoir 118 immediately before the liquid is pumped from the reservoir. This embodiment is characterized in that the remaining amount of liquid in the reservoir after pumping the liquid from the reservoir is measured after each measurement, and the amount of liquid to be pumped to fill the reservoir with the predetermined amount of liquid is calculated based on the measured remaining amount of liquid so that the reservoir is filled with the predetermined amount of liquid at the time of the next analysis cycle. This compensates for the accuracy of the tube pump's pumping.

[0052] Furthermore, when controlling the supply of each liquid using a tube pump, changing the rotation speed of the motor inside the pump did not necessarily stabilize the amount of liquid delivered, which increased wear and accelerated deterioration of the tubes, posing a risk of reducing the discharge accuracy associated with the supply of each liquid.To ensure consistent and appropriate reagent delivery, it was necessary to control the amount of liquid delivered while maintaining a constant rotation speed of the motor.

[0053] In this embodiment, as shown in FIG. 5, while the motor rotation speed of the tube pump 212 is maintained constant, the presence or absence and amount of supply of each liquid in the next cycle is determined based on the liquid level height immediately after each liquid supply in the previous cycle, and the increase or decrease in the motor rotation speed is corrected and converted into an actual step number and set, thereby making it possible to variable supply for all remaining liquid amounts and achieving efficient liquid supply without excess or deficiency even after the detection cycle.

[0054] 101: automatic analyzer, 102: reservoir mechanism, 103: first liquid bottle, 104: second liquid bottle, 105: detergent bottle, 106: pure water bottle, 107: waste liquid bottle, 108: first liquid feed pump (tube pump), 109: second liquid feed pump (tube pump), 110: incubator (reaction disk), 111: dispensing unit, 112: specimen container, 113: specimen holding unit (specimen disk), 114: reagent container, 115: reagent holding unit (reagent disk), 116: specimen / reagent shared disk, 117: transport unit, 118: storage unit, 119: control device, 120: analysis unit, 121 : First liquid storage section, 122: Second liquid storage section, 123: Reaction vessel, 124: Reaction vessel holding section, 125: Control section, 126: Memory section, 127: Calculation section, 128: Operation section, 129: Display section, 201: Liquid level detection sensor, 202: Suction nozzle, 203: Operation stage (mounting section), 204: Operation mechanism, 205: First flow path, 206: Second flow path, 207: Third flow path, 208: Fourth flow path, 209: Fifth flow path, 210: Pump, 211: Sixth flow path, 212: Tube pump, 301: Liquid level detection section, 302: Drive amount calculation section, 303: Residual liquid amount calculation section, 304: Determination section, 305: Actual step number setting section.

Claims

1. An automatic analyzer comprising a measuring mechanism for measuring the remaining amount of liquid in a container for storing a liquid used for analyzing a specimen, a tube pump for transferring the liquid to the container, and a stepping motor for rotationally driving the tube pump at a predetermined constant rotational speed, wherein a storage unit stores the relationship between the remaining amount of liquid in the container and the number of rotational driving steps of the stepping motor for rotationally driving the tube pump so that the liquid in the container becomes a predetermined amount for each liquid transfer amount; a determination unit determines the liquid transfer amount to be transferred to the container in the next analysis cycle based on the remaining amount of liquid used in the previous analysis cycle in the container measured by the measuring mechanism; and a control unit controls the rotational driving of the stepping motor so as to transfer the liquid to be used in the next analysis cycle to the container based on the relationship between the liquid transfer amount to be transferred to the container determined by the determination unit, the remaining amount of liquid in the container stored in the storage unit, and the number of rotational driving steps of the stepping motor for rotationally driving the tube pump so that the liquid in the container becomes a predetermined amount.

2. The automatic analyzer according to claim 1, wherein the relationship between the number of rotational driving steps of the stepping motor for rotationally driving the tube pump so that the liquid in the container becomes a predetermined amount is represented by y = ax + b, where y is the number of rotational driving steps of the stepping motor, x is the remaining amount of liquid in the container, a is a coefficient determined from the specifications of the tube pump, etc., and b is a constant determined by the liquid transfer amount.

3. The automatic analyzer according to claim 2, wherein b is determined by the analysis item of the automatic analyzer using the liquid.

4. The automatic analyzer according to claim 1, wherein the storage unit stores an upper limit value of the liquid amount in the container determined in advance, and includes a determination unit for determining whether the liquid amount in the container measured by the measuring mechanism exceeds the upper limit value, and when the determination unit determines that the liquid amount in the container exceeds the upper limit value, the control unit controls to skip the operation of transferring the liquid to be used in the next analysis cycle to the container.

5. The automatic analyzer according to claim 4, wherein the storage unit stores a lower limit value of the liquid volume in the container determined in advance, the determination unit has a function of determining whether the liquid volume in the container measured by the measurement mechanism is less than the lower limit value, and when the determination unit determines that the liquid volume in the container is less than the lower limit value, an automatic analyzer characterized by comprising a notification mechanism for notifying the fact.

6. The automatic analyzer according to claim 2, wherein the liquid is classified into a first liquid for detecting a component contained in the specimen and a second liquid for cleaning a liquid feeding unit and / or an analysis unit, and the formula y = ax + b is a different formula for the first liquid and the second liquid.

7. An analysis method for an automatic analyzer including a measurement mechanism for measuring a remaining amount of liquid in a container storing a liquid used for analyzing a specimen, a tube pump for transferring the liquid to the container, and a stepping motor for rotationally driving the tube pump at a predetermined constant rotation speed, the method including: a first step of measuring, by the measurement mechanism, a remaining amount of the liquid used in the previous analysis cycle in the container; a second step of determining a liquid transfer amount to be transferred to the container in the next analysis cycle based on a relationship between the remaining amount of the liquid used in the previous analysis cycle in the container measured in the first step, the remaining amount of the liquid in the container for each liquid transfer amount, and the number of rotation driving steps of the stepping motor for rotationally driving the tube pump so that the liquid in the container becomes a predetermined amount; and a third step of rotationally driving the stepping motor so as to transfer the liquid to be used in the next analysis cycle to the container based on a relationship between the liquid transfer amount to be transferred to the container determined in the second step, the remaining amount of the liquid in the container, and the number of rotation driving steps of the stepping motor for rotationally driving the tube pump so that the liquid in the container becomes a predetermined amount.

8. In the analysis method of the automatic analyzer according to claim 7, a determination step of determining whether the liquid volume in the container measured by the measurement mechanism exceeds a predetermined upper limit value of the liquid volume in the container, and when it is determined in the determination step that the liquid volume in the container exceeds the upper limit value, a step of skipping the operation of transferring the liquid to be used in the next analysis cycle to the container. A method for analyzing an automatic analyzer, characterized by comprising:

9. In the analysis method of the automatic analyzer according to claim 7, a determination step of determining whether the liquid volume in the container measured by the measurement mechanism is less than a predetermined lower limit value of the liquid volume in the container, and when it is determined in the determination step that the liquid volume in the container is less than the lower limit value, a notification step of notifying to that effect. A method for analyzing an automatic analyzer, characterized by comprising:

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