Dispensing device and probe state verification method

Abstract

The purpose of the present invention is to provide a dispensing device and a method for checking the state of a probe, which are capable of suppressing a decrease in dispensing accuracy and ascertaining the appropriate replacement time of the probe. Therefore, the present invention is a dispensing device provided with: a probe that sucks and discharges a liquid; a sensor that detects contact of the tip of the probe; a drive unit that drives the probe in the vertical direction; and a control unit that controls the drive unit, in which the control unit performs a confirmation operation of a change in length of the probe by lowering the probe by the drive unit until contact with a predetermined reference surface constituting a part of the dispensing device is detected.

Description

Technical Field

[0001] The present invention relates to a dispensing device equipped with a probe and a method for confirming the state of the probe. Background Art

[0002] For example, in an analysis device, a non-sealed specimen container with an open top is generally used. However, in recent years, sealed specimen containers with an opening sealed with a stopper such as a vacuum blood collection tube have become widely popular, and there is an increasing demand for a dispensing device that can directly collect specimens without opening the sealed specimen container. In addition, when a specimen is sucked from such a sealed specimen container, for example, Patent Document 1 discloses an automatic analysis device that repeatedly penetrates the stopper of the container with the same probe to perform dispensing. Due to wear of the front end of the probe, the performance of penetrating the stopper deteriorates, so the penetration performance is monitored to determine the replacement period of the probe.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-102427 Summary of the invention

[0006] Problems to be solved by the invention

[0007] The technique described in Patent Document 1 only monitors the penetration performance of the probe, so even if the stopper of the container can be reliably penetrated, it is not necessarily possible to ensure the accuracy of dispensing the liquid. That is, according to the inventor's research, when the stopper is repeatedly penetrated by the probe, the length of the probe becomes shorter, and the action of bringing the probe into contact with the reaction container when the specimen is ejected is deviated, resulting in a possibility of reducing the dispensing accuracy.

[0008] An object of the present invention is to provide a dispensing device and a method for confirming the state of a probe, which can suppress a decrease in dispensing accuracy and grasp an appropriate replacement time for a probe.

[0009] Solutions to Solve Problems

[0010] In order to solve the above-mentioned problems, the present invention provides a dispensing device, which comprises: a probe that sucks and ejects liquid; a sensor that detects contact of the front end of the probe; a driving unit that drives the probe in the up and down directions; and a control unit that controls the driving unit, wherein the control unit uses the driving unit to lower the probe until contact with a predetermined reference surface that constitutes a part of the dispensing device is detected, thereby performing a confirmation action of the length change of the probe.

[0011] Effects of the Invention

[0012] According to the present invention, it is possible to provide a dispensing device and a method for checking the state of a probe that can suppress a decrease in dispensing accuracy and grasp an appropriate replacement timing of a probe. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram showing the main structure of an automatic analyzer.

[0014] Figure 2 This is a schematic diagram showing the structure of a sample dispensing mechanism.

[0015] Figure 3 It is a diagram for explaining a structure for detecting contact of the tip of the sample dispensing probe.

[0016] Figure 4 The figure shows the positional relationship between a new sample dispensing probe, a sample dispensing probe with a worn tip, and a reference surface.

[0017] Figure 5 This is a flowchart showing the operation when measuring the length of the probe before use.

[0018] Figure 6 This is a timing diagram showing the operation when measuring the probe length.

[0019] Figure 7 This is a flowchart showing the operation when confirming the state of the probe based on the change in the probe length.

[0020] Figure 8 The diagram shows the positional relationship between the probe before use and the probe after use and the reaction container when the probe is lowered by a predetermined amount from the origin height.

[0021] Fig. 9 This is a schematic diagram showing the concept of correcting the probe lowering amount.

[0022] Fig.10 This is a graph showing an example of the relationship between the change in the probe descent amount and the number of dispensing times.

[0023] Fig.11 This is a diagram showing an example of a probe status confirmation screen.

[0024] Fig.12 This is a diagram showing an example of a probe length setting screen. DETAILED DESCRIPTION

[0025] The embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the constituent elements (including element steps, etc.) are not necessarily essential unless otherwise specified or unless they are clearly considered to be essential in principle.

[0026] In this embodiment, an automatic analyzer is used as an example for description. The automatic analyzer can be, for example, a biochemical automatic analyzer, an immune automatic analyzer, or a gene automatic analyzer. However, this is only an example of an automatic analyzer, and widely includes a device for analyzing a specimen such as plasma, serum, and urine by mixing the specimen with various reagents. For example, it also includes a mass analyzer for clinical examination, a coagulation analyzer for measuring the coagulation time of blood, and the like. In addition, it can also be applied to a composite system of them and a biochemical automatic analyzer, an immune automatic analyzer, etc., or an automatic analysis system using them.

[0027] [Structure of automatic analysis device]

[0028] Figure 1 This is a schematic diagram showing the main structure of the automatic analysis device. Figure 1 As shown, the automatic analyzer includes a computer 1, a sample dispensing mechanism 2, a reagent cold storage 5, a reagent dispensing mechanism 3, and the like.

[0029] The computer 1 has an output unit, an input unit, and a storage unit. The output unit displays analysis results, alarms, etc. to the user, and is, for example, a display. The input unit is used by the user to input text and numerical values ​​in order to set the operating conditions of the device, and is, for example, a keyboard. The storage unit is used to store analysis results and set values, and is, for example, a memory. The user performs analysis commissions and various settings by operating the input unit while observing the output unit.

[0030] The sample dispensing mechanism 2 receives the sample container (in Figure 1 The specimen is sucked by a reagent cold storage 5 (not shown in the figure) and ejected into the reaction container 4. The reagent cold storage 5 keeps the reagent mixed with the specimen cold, and its top is closed by a lid. The reagent dispensing mechanism 3 sucks the reagent from the hole provided in the lid of the reagent cold storage 5 and ejects it into the reaction container 4. The specimen and the reagent ejected into the reaction container 4 are mixed by a stirring mechanism (not shown) to prepare a mixed solution in the reaction container 4. The absorbance of the mixed solution is measured by an analysis unit (not shown), and the control unit (not shown) calculates the concentration of a predetermined component contained in the mixed solution based on the measurement result. In addition, the control unit also controls the operation of each mechanism such as the specimen dispensing mechanism.

[0031] [Structure of dispensing mechanism]

[0032] Figure 2 The sample dispensing mechanism 2 is a schematic diagram showing the structure of the sample dispensing mechanism. The sample dispensing mechanism 2 includes a horizontal driving unit, a vertical driving unit, a syringe, and the like, in addition to the sample dispensing probe 10, although not shown.

[0033] On the other hand, the specimen 11 is stored in a specimen container 12, and a single or a plurality of specimen containers 12 are transported to the dispensing position by a transport mechanism (not shown) while being mounted on a specimen rack 14. In this embodiment, the specimen container 12 is enclosed by a stopper 13, such as a vacuum test tube, but an unsealed specimen container 12 may also be included.

[0034] When dispensing a specimen, the control unit first controls the horizontal driving unit of the specimen dispensing mechanism 2 to drive the specimen dispensing probe 10 in the horizontal direction to move it to a position above the specimen container 12. Next, the control unit controls the vertical driving unit of the specimen dispensing mechanism 2 to drive the specimen dispensing probe 10 downward in the vertical direction to penetrate the stopper 13 of the specimen container 12. Thereafter, the control unit actuates the syringe while the specimen dispensing probe 10 is immersed in the specimen 11, thereby sucking a predetermined amount of the specimen 11 into the specimen dispensing probe 10.

[0035] When the aspiration of the specimen 11 is completed, the control unit controls the vertical drive unit to raise the specimen dispensing probe 10, and then controls the horizontal drive unit to move the specimen dispensing probe 10 to a position above the reaction container 4. Next, the control unit controls the vertical drive unit of the specimen dispensing mechanism 2 to lower the specimen dispensing probe 10, and then operates the syringe to eject a predetermined amount of the specimen 11 from the specimen dispensing probe 10 into the reaction container 4.

[0036] In addition, when the control unit moves the sample dispensing probe 10 to the above-mentioned positions and stops, a control method is used to stop the driving unit based on a detection signal of a predetermined sensor, or a control method is used to provide the driving unit with a predetermined movement amount from the reference position to the stop position. In addition, the front end of the sample dispensing probe 10 is sharpened so as to be able to penetrate the plug 13.

[0037] Furthermore, each time the control unit completes the suction and ejection of one sample, it moves the sample dispensing probe 10 to the cleaning tank 15, and ejects cleaning water from the cleaning tank 15 to the sample dispensing probe 10, thereby cleaning the sample dispensing probe 10. Thus, when the same sample dispensing probe 10 is used to dispense another sample, mixing of the previous sample can be prevented.

[0038] Figure 3 FIG. 2 is a diagram for explaining a structure for detecting contact of the tip of a sample dispensing probe. Figure 3As shown, the specimen dispensing mechanism 2 of the present embodiment also includes a stopper 21, a detection plate 23, a contact detection sensor 20, and a spring 22. The stopper 21 limits the specimen dispensing probe 10 from moving downward beyond a predetermined range. The detection plate 23 is fixed to the specimen dispensing probe 10 via a connecting portion 24 above the stopper 21. The contact detection sensor 20 is a sensor that detects contact with the front end of the specimen dispensing probe 10 by blocking light when the detection plate 23 enters the irradiation range (detection range) of its light. The spring 22 is used to press the connecting portion 24 that is integrated with the specimen dispensing probe 10 downward.

[0039] When the object is not in contact with the front end of the sample dispensing probe 10, Figure 3 As shown on the left side of the figure, the connection part 24 is pressed against the stopper 21 by the pressing force of the spring 22 and is in a positioned state, and the detection plate 23 does not exist in the detection range of the contact detection sensor 20. However, when the object 25 contacts the front end of the probe during the descent of the sample dispensing probe 10, as shown in FIG. Figure 3 As shown on the right side of FIG. 2 , the connection portion 24 overcomes the pressing force of the spring 22 and moves upward, so the detection plate 23 also moves upward and enters the detection range of the contact detection sensor 20 .

[0040] When the control unit detects the entry of the detection plate 23 by the contact detection sensor 20, it controls the up-down drive unit to stop the descending action of the sample dispensing probe 10. Therefore, even if the sample dispensing probe 10 contacts the object 25 during the descending process, the sample dispensing probe 10 stops safely without damaging the device. When the front end of the sample dispensing probe 10 leaves the object 25, the connection part 24 is pressed against the stopper 21 by the pressing force of the spring 22, and returns to the positioned state.

[0041] If the object 25 is a reaction container 4, a cleaning tank 15, etc., the contact is detected by the same action. However, when the specimen dispensing probe 10 is made to penetrate the stopper 13 of the specimen container 12 in order to aspirate the specimen, it is desirable to perform control such that the descending action of the specimen dispensing probe 10 is not stopped even if the detection plate 23 enters the detection range of the contact detection sensor 20.

[0042] Figure 4 This figure shows the positional relationship between a new sample dispensing probe, a sample dispensing probe with a worn tip, and a reference surface. Figure 4 As shown, the position of the tip of the probe at the origin height is different between a new sample dispensing probe (hereinafter referred to as the probe 10a before use) and a sample dispensing probe with a worn tip (hereinafter referred to as the probe 10b after use). Here, the origin height of the probe refers to the height of the probe when the motor of the upper and lower driving part constituting the sample dispensing mechanism 2 is at the origin position. Figure 4It can be seen that the position of the detection plate 23 and the like of the probe 10b after use is the same as that of the probe 10a before use, but the position of the front end of the probe 10b after use is higher than that of the front end of the probe 10a before use. This is because when the probe is used for repeated dispensing, especially when the probe repeatedly penetrates the plug 13, the length of the probe becomes shorter. Therefore, when the probe is lowered from the origin height to contact with the reference surface 31, the lowering amount Y of the probe 10b after use is longer than the reference lowering amount X of the probe 10a before use.

[0043] [Method for measuring the length of the probe before use (reference length)]

[0044] Figure 5 This is a flowchart showing the operation when measuring the length of the front probe. Figure 6 This is a timing diagram showing the operation when measuring the probe length. First, the user or the like installs the pre-use probe 10a of the new sample dispensing probe 10 on the sample dispensing mechanism 2 of the automatic analyzer. Then, the user performs a predetermined operation using the input unit to instruct the start of the measurement operation of the reference length (reference descent amount).

[0045] Then, the control unit controls the horizontal driving unit of the sample dispensing mechanism 2 to move the pre-use probe 10a to a predetermined horizontal home position (step S101). When the pre-use probe 10a is in the home position, its vertical position is the same as the origin height.

[0046] Next, the control unit controls the horizontal driving unit of the sample dispensing mechanism 2 to move the pre-use probe 10a to a predetermined reference plane 31 (see FIG. 3 ) constituting a part of the automatic analyzer. Figure 4 ) (step S102). The movement at this time is, for example, parallel movement to the right or rotational movement to the right, which is equivalent to Figure 6 Horizontal movement A.

[0047] Afterwards, the control unit controls the up and down driving units of the specimen dispensing mechanism 2 to lower the front probe 10a. When the contact detection sensor 20 detects contact with the reference surface 31, the lowering of the front probe 10a is stopped (step S103). At this time, the control unit calculates the amount of descent from the origin height based on the action log of the up and down driving units, and stores the calculation result as the reference descent amount X in the storage unit (step S104). In addition, if the front end of the front probe 10a contacts the reference surface 31, the detection plate 23 enters the irradiation range of the light of the contact detection sensor 20 and becomes dark. Figure 6 Contact is detected as shown.

[0048] After that, the control unit controls the vertical drive unit to raise the probe 10a to the origin height before use. Furthermore, the control unit controls the horizontal drive unit to move the probe 10a to the original position before use. The movement at this time is, for example, parallel movement to the left or rotational movement to the left, which is equivalent to Figure 6 Horizontal movement B.

[0049] In addition, if the reference surface 31 is set to be, for example, a plane constituting the cleaning tank 15, there is an advantage that even if the specimen adheres to the reference surface 31 due to contact with the specimen dispensing probe 10, the specimen can be cleaned using the cleaning tank 15. However, instead of causing a deviation in the positional relationship with the device like the bottom surface of the container, as long as it is a flat surface that forms a part of the device and does not change the positional relationship with the device (especially the height), a portion other than the cleaning tank 15 may be used as the reference surface 31. In addition, the reference surface 31 is not limited to an existing portion in the device, and may be formed by newly providing a metal portion that is difficult to deform within the movement trajectory of the specimen dispensing probe 10.

[0050] [Status confirmation method based on changes in probe length]

[0051] Figure 7 This is a flowchart showing the operation of checking the state of the probe based on the change in the probe length. When the probe state checking operation is started at a predetermined timing described later, the length (drop amount) of the used probe 10b worn by repeated dispensing is measured.

[0052] First, the control unit controls the horizontal driving unit of the sample dispensing mechanism 2 to move the used probe 10 b to an initial position located at a predetermined horizontal position (step S201 ).

[0053] Next, the control unit controls the horizontal drive unit of the sample dispensing mechanism 2 to move the used probe 10b above the reference plane 31 (step S202). Thereafter, the control unit controls the vertical drive unit of the sample dispensing mechanism 2 to lower the used probe 10b, and when the contact detection sensor 20 detects contact with the reference plane 31, the lowering of the used probe 10b is stopped (step S203). At this time, the control unit calculates the amount of descent from the origin height based on the action log of the vertical drive unit, and stores the calculated result as the descent amount Y in the storage unit (step S204).

[0054] Next, the control unit performs the control based on the drop amount Y measured in step S204 and the Figure 5 The difference between the reference drop amount X measured in the calculation and the change in drop amount α (refer to Figure 4) (Step S205). In addition, in reality, there is a certain detection delay from the time when the sample dispensing probe 10 contacts the reference surface 31 to the time when the contact detection sensor 20 detects the entry of the detection plate 23. However, this detection delay is usually constant regardless of the change in the length of the sample dispensing probe 10 and does not affect the measurement of the drop amount X and the reference drop amount Y. Therefore, in this embodiment, the detection delay is not considered.

[0055] Here, when the specimen dispensing probe 10 is worn due to repeated use, the change in the amount of descent α gradually increases, and the specimen dispensing probe 10 eventually needs to be replaced. Therefore, the control unit outputs a warning alarm (first alarm) at a stage where dispensing is impossible without replacing the specimen dispensing probe 10. In addition, the control unit also outputs a caution alarm (second alarm) at a stage when the replacement period of the specimen dispensing probe 10 is approaching. In order to determine whether it is necessary to output such two alarms, two thresholds are pre-stored in the storage unit. In addition, in the present embodiment, two alarms and two thresholds are cited as examples for explanation, but the types of alarms and thresholds may be one, or may be three or more.

[0056] The first threshold value A is a threshold value for determining whether a warning alarm needs to be output. When the change amount α reaches this threshold value, the required dispensing accuracy cannot be guaranteed, and it is considered that the probe 10b after use needs to be replaced. The second threshold value B is a threshold value for determining whether a warning alarm needs to be output. When the change amount α reaches this threshold value, it is considered that the replacement period of the probe 10b after use is approaching. In addition, the second threshold value B is smaller than the first threshold value A, and these threshold values ​​are stored in the storage unit.

[0057] The control unit compares the change amount α calculated in step S205 with the first threshold value A and the second threshold value B (step S206). When the change amount α is greater than the first threshold value A, the control unit outputs a warning alarm (step S207) and stops the dispensing operation (step S208). In step S208, if it is before the start of a series of sample dispensing operations, the subsequent dispensing operations are not performed, and if it is in the middle of a series of sample dispensing operations, the dispensing operation after the dispensing of the remaining samples is completed may not be performed.

[0058] On the other hand, if it is determined in step S206 that the change amount α is less than the first threshold value and greater than the second threshold value B, the control unit outputs a warning alarm (step S209). In this case, since the dispensing accuracy can be guaranteed, the dispensing operation starts / continues (step S210), and when all the requested specimens are dispensed, the dispensing operation ends (step S211).

[0059] Furthermore, in step S206, when it is determined that the change amount α is smaller than the second threshold value B, the control unit starts / continues the dispensing operation without outputting an alarm (step S210), and ends the dispensing operation when all the samples have been dispensed (step S211).

[0060] In this way, by determining the state of the probe based on the change in the length of the probe, it is possible to grasp the appropriate replacement time of the probe. In addition, it is also possible to determine abnormalities such as bending and curvature of the probe.

[0061] [Probe descent correction method]

[0062] When ejecting the sample sucked by the sample dispensing probe 10 into the reaction container 4 , the control unit gives a predetermined operation amount (eg, number of pulses) to the vertical drive unit of the sample dispensing mechanism 2 in order to lower the sample dispensing probe 10 by a predetermined distance from the origin height. Figure 8 The diagram shows the positional relationship between the probe before use and the probe after use and the reaction container when the probe is lowered by a predetermined amount from the origin height.

[0063] like Figure 8 As shown in FIG. 1 , the position of the probe tip is different between the probe 10a before use and the probe 10b after use, even if the probe tip is lowered by the same amount from the origin height. Figure 8 It can be seen that the tip of the probe 10a is in contact with the bottom surface of the reaction container 4 before use, but the tip of the probe 10b is separated from the bottom surface of the reaction container 4 by a change amount α after use. Here, in order to maintain the dispensing accuracy, the sample dispensing probe 10 usually ejects the sample in a state of contact with the bottom surface of the reaction container 4. However, if the sample dispensing probe 10 becomes shorter due to repeated use, and the sample is ejected in a state of being separated from the bottom surface of the sample container 12, the dispensing accuracy may be reduced. Therefore, in this embodiment, according to the use Figure 7 The difference between the probe descent amount Y in the state confirmation operation and the reference descent amount X is used to correct the probe descent amount in the specimen ejection operation.

[0064] Fig. 9: is a schematic diagram showing the idea of ​​correcting the probe descent amount. When the specimen is ejected using the pre-use probe 10a, the control unit gives a predetermined motion amount to the up-down drive unit of the specimen dispensing mechanism 2, so that the pre-use probe 10a is lowered from the origin height 37 by the descent amount X1. On the other hand, when the specimen is ejected using the post-use probe 10b, the control unit gives a predetermined motion amount to the up-down drive unit of the specimen dispensing mechanism 2, so that the post-use probe 10b is lowered from the origin height by the corrected descent amount Y1. Here, the corrected descent amount Y1 is obtained by adding the change amount α calculated in the above-mentioned state confirmation action to the pre-correction descent amount X1 as a reference. In this way, by correcting the probe descent amount according to the degree of wear, that is, the length of the probe, the front end of the probe can be reliably contacted with the bottom surface of the specimen container 12, and the dispensing accuracy can be ensured. In addition, before the change amount α reaches the first threshold value A, the dispensing accuracy can be ensured by correcting the probe descent amount, but when the change amount reaches the first threshold value A, the dispensing accuracy cannot be ensured in the correction of the probe descent amount, and the probe needs to be replaced.

[0065] [Method for predicting the replacement time of the probe]

[0066] Fig.10 : is a graph showing an example of the relationship between the change in the probe descent amount and the number of dispensing times. The change in the probe descent amount α is calculated each time the state confirmation operation of the rear probe 10b is used, and is stored in the storage unit. Fig.10 The multiple points 51 drawn in the figure represent the change of the calculated change amount α in each confirmation action (vertical axis) and the change of the cumulative number of dispensing times during the calculation (horizontal axis). The control unit generates an approximate curve 52 connecting these multiple points 51 and the origin, calculates the slope of the approximate curve 52, and thereby predicts the number of dispensing times N when the change amount α reaches the first threshold value A. A and the number of dispensing times N when the second threshold B is reached B By outputting the prediction result, the control unit can inform the user of the benchmark for the replacement period of the probe and urge the user to prepare for the replacement of the probe. In addition, the prediction is not limited to the number of injections until each threshold is reached. For example, the control unit can also predict the number of days until each threshold is reached by making an approximate curve for the relationship between the change amount α and the number of days.

[0067] [Probe status confirmation screen]

[0068] Fig.11 1 is a diagram showing an example of a probe status confirmation screen. For example, in a checklist related to maintenance of an automatic analyzer, when a user performs a predetermined operation using the input unit, the control unit reads out the history of status confirmation actions stored in the storage unit and displays the status confirmation action. Fig.11The status confirmation screen (maintenance history) shown in the figure is displayed on the output unit. The date and time of the status confirmation action of the probe is displayed in the confirmation action date and time display column 41. The change amount α calculated by the status confirmation action is displayed in the length change amount display column 42. The displayed change amount α can be the number of pulses given to the upper and lower drive parts, but it is easier for the user to grasp it by converting it into length. In addition, it is also possible to display the shortening degree when the length of the probe 10a before use is set to 100 in percentage or graph. The cumulative number of dispensing times when the status confirmation action is performed is displayed in the dispensing times display column 43. In addition, when the change amount α turns to decrease (becomes zero), the probe is replaced, so the cumulative number of dispensing times can also be automatically reset to zero. The remaining number of dispensing times until the change amount α reaches the first threshold A is displayed in the first threshold A display column 44, and the remaining number of dispensing times until the change amount α reaches the second threshold B is displayed in the second threshold B display column 45. In addition, the remaining number of dispensing times displayed in these columns is the number of times used. Fig.10 predicted by the aforementioned method.

[0069] It is preferred to periodically perform the status confirmation operation of the probe. For example, it can also be incorporated into the preparation operation performed at the beginning of the analysis operation and automatically performed during each analysis operation. Fig.11 As shown, a confirmation action execution button 46 may be provided on the status confirmation screen, and when the button is operated, the status confirmation action of the probe is immediately executed.

[0070] [Probe length measurement setting screen]

[0071] Fig.12 This figure shows an example of a probe length setting screen. Fig.12 The timing of the status confirmation action of the probe is appropriately specified in the screen shown. For example, it can be specified that the status confirmation action of the probe is performed before the dispensing action of a series of specimens is started, or it can be specified that the status confirmation action of the probe is performed after the dispensing action of a series of specimens is started. In addition, the status confirmation action of the present embodiment is performed in a loop, so even in the middle of a series of dispensing actions, as long as there is an idle loop, it can be performed at this timing. In addition, a predetermined number of dispensing times can also be specified in advance, and the status confirmation action of the probe is performed when the cumulative number of dispensing times reaches the specified number. In addition, when the specified number (for example, 500 times) is reached, in the case of being in the middle of a series of specimen dispensing actions, the status confirmation action of the probe can also be performed at the time point when the dispensing of the remaining specimens is completed (for example, 520 times).

[0072] The present invention is not limited to the above-mentioned embodiment, and various modifications are possible. For example, in the above-mentioned embodiment, as the contact detection sensor 20, a sensor that detects the contact of the front end of the probe by the entry of the detection plate 23 is used, but it is also possible to replace this sensor with a sensor that detects the contact of the front end of the probe by detecting changes in electrostatic capacitance or pressure. In addition, in the above-mentioned embodiment, the sample dispensing probe 10 that sucks and ejects the sample is described, but it can also be applied to a dispensing probe that sucks and ejects other liquids such as reagents and detergents.

[0073] Furthermore, in the aforementioned embodiment, an automatic analyzer having an analysis unit for analyzing a mixed solution containing a sample and a reagent is described as an example, but the present invention can also be applied to a dispensing device that does not have an analysis unit and only performs sample dispensing. For example, it can also be applied to a sample transport device that dispenses a sample from a sample container that is inserted by a sample inserting unit and sealed by a stopper to another container, and transports the container containing the sub-samples.

[0074] Explanation of symbols

[0075] 1—computer; 2—sample dispensing mechanism; 3—reagent dispensing mechanism; 4—reaction container; 5—reagent cold storage; 10—sample dispensing probe; 10a—probe before use; 10b—probe after use; 11—sample; 12—sample container; 13—stopper; 14—sample rack; 15—cleaning tank; 20—contact detection sensor; 21—stopper; 22—spring; 23—detection plate; 24—connecting part; 25—object; 37—origin height; 51—point; 52—approximate curve; 41—action confirmation date and time display bar; 42—length change display bar; 43—dispensing number display bar; 44—first threshold value A display bar; 45—second threshold value B display bar; 46—action confirmation execution button.

Claims

1. A dispensing device comprising: a probe that draws in and ejects liquid; a sensor that detects contact of the front end of the probe; a driving unit that drives the probe in an up-down direction; and a control unit that controls the driving unit, The dispensing device is characterized in that The control unit uses the drive unit to lower the probe until contact with a predetermined reference surface constituting a part of the dispensing device is detected, thereby performing an operation of confirming a change in length of the probe.

2. The dispensing device according to claim 1, characterized in that: The control unit outputs an alarm when a difference between a descent amount of the probe in the confirmation operation and a reference descent amount is equal to or larger than a predetermined threshold value.

3. The dispensing device according to claim 2, characterized in that: The control unit outputs a first alarm and does not eject the liquid when the difference is greater than a first threshold value, and outputs a second alarm different from the first alarm and ejects the liquid when the difference is greater than a second threshold value smaller than the first threshold value.

4. The dispensing device according to claim 2, characterized in that: The control unit predicts the number of dispensings until the difference reaches the threshold value based on the relationship between the change in the number of dispensings by the probe and the change in the difference.

5. The dispensing device according to claim 1, characterized in that: The control unit corrects the descent amount of the probe in the liquid ejection operation based on a difference between the descent amount of the probe in the confirmation operation and a reference descent amount.

6. The dispensing device according to claim 5, characterized in that: If the difference is equal to or greater than a first threshold value, a first alarm is output and the ejection operation of the liquid is not performed.

7. The dispensing device according to claim 1, characterized in that: The control unit performs the confirmation operation at a preset timing.

8. The dispensing device according to claim 1, characterized in that: The probe penetrates the stopper of the closed container and aspirates the liquid in the container.

9. The dispensing device according to claim 1, characterized in that: A cleaning tank is also provided, which cleans the probe. The reference plane is a plane constituting the cleaning tank.

10. A method for confirming the state of a probe, which is a method for confirming the state of a probe of a dispensing device for dispensing liquid, characterized in that: The probe is lowered until contact with a predetermined reference surface constituting a part of the dispensing device is detected, thereby confirming a change in the length of the probe.

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