Specimen conveyor device

Abstract

The specimen conveying device of the present invention maintains the specimen's stopping position accuracy with high precision when the device is started, and suppresses liquid sloshing during conveying. In the specimen conveying device comprising a plurality of coils for conveying a conveying container for conveying the specimen, a coil driving unit, and a control unit, the control unit has a liquid sloshing determination unit for determining the liquid sloshing of the specimen based on the speed change of the specimen. The control unit sets a first interval (S1) on a side away from the stop coil (3) near the stop position closest to the specimen, and sets a second interval (S2) on a side closer to the stop coil (3) than the first interval (S1). When the specimen exists in the first interval (S1), a first current is set as the current for energizing the stop coil (3), and when the specimen exists in the second interval (S2), a second current is set as the current for energizing the stop coil (3). The first current is set to a magnitude that suppresses the liquid sloshing of the specimen based on determination information of the liquid sloshing determination unit (65), and the second current is set to a current value greater than the first current.

Description

Technical Field

[0001] The present invention relates to a specimen analysis system suitable for analyzing biological samples (hereinafter referred to as specimens) such as blood and urine, and a specimen transport device of a specimen preprocessing device for performing preprocessing required for analysis. Background Art

[0002] In specimen processing devices used for clinical examinations, the indicated analysis items are examined for specimens (samples) such as blood, plasma, serum, urine, and other body fluids. These specimen processing devices can connect multiple devices with various functions to automatically process each process. In other words, in order to rationalize the business of the examination room, the analysis units of multiple analysis fields such as biochemistry and immunology are connected through a conveyor line and operated as a single device. Conventional conveyor lines are mainly driven by belts. If the transmission stops due to some abnormality in the middle of the transmission, the specimen cannot be supplied to the device on the downstream side. In addition, with the advancement of medical care and the development of an aging society, the diversification of specimen processing content and the increase in the number of specimens are foreseeable, and a variety of specimens need to be transported faster. Therefore, in order to improve the processing capacity of specimen processing devices, electromagnetic transmission methods are being studied to achieve high-speed transmission of specimens, large-scale simultaneous transmission, and transmission in multiple directions.

[0003] As an example of an electromagnetic transmission method, there is a laboratory sample distribution system described in Japanese Patent Laid-Open No. 2017-227635 (Patent Document 1). The laboratory sample distribution system includes a plurality of sample container conveyors, each of which includes a magnetically active element in the form of a permanent magnet. Thus, in the laboratory sample distribution system of Patent Document 1, the magnetic field generated by the electromagnetic actuator drives the sample container conveyor on the entire transfer plane. In addition, in the laboratory sample distribution system of Patent Document 1, the magnetic field generated by the permanent magnet can be detected by a position sensor, and feedback on the position of the sample container conveyor is received (see paragraphs 0063-0065).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-227635 Summary of the Invention

[0007] Technical problem to be solved by the invention

[0008] The laboratory sample dispensing system of Patent Document 1 discloses a technique for conveying a sample container conveyor body by detecting the position of a sample using a position sensor, but does not describe a method for moving and stopping the sample container conveyor body.

[0009] In an electromagnetic actuator, current is applied to a coil, and the effective thrust generated by the coil is used to transport the sample. In this case, if the amount of current applied to the coil and the switching position of the coil applying the current are not properly controlled, the fluctuation in the sample transport speed immediately after the switching becomes larger, causing significant liquid sloshing. In addition, because the coil has magnetic resistance (a force acting in the opposite direction of travel) near the top, if the coil current is not controlled to take into account the magnetic resistance, the sample container transport body cannot be stopped at the target stop position.

[0010] An object of the present invention is to provide a specimen transport device capable of controlling a specimen stop position with high precision while suppressing liquid sloshing during specimen transport.

[0011] Technical solutions to technical problems

[0012] In order to achieve the above-mentioned purpose, the specimen conveying device of the present invention comprises: a conveying container, which has a magnet or a magnetic body and a holding part for holding the specimen; a plurality of coils for conveying the conveying container; a coil driving part for applying voltage to the plurality of coils; and a control part for controlling the coil driving part, the control part having a liquid shaking determination part for determining the liquid shaking of the specimen according to the speed change of the specimen, the control part setting a first interval on the side away from the stop coil near the stop position closest to the specimen, and setting a second interval on the side closer to the stop coil than the first interval, and setting a first current as the current for energizing the stop coil when there is a specimen in the first interval, and setting a second current as the current for energizing the stop coil when there is a specimen in the second interval, the first current being set to a size at which the liquid shaking of the specimen is suppressed based on the determination information of the liquid shaking determination part, and the second current being set to a current value greater than the first current. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic configuration diagram of a specimen transport device 1 according to an embodiment of the present invention.

[0014] Figure 2 It is a schematic diagram showing a part of a cross-sectional structural example of the specimen transport device 1 .

[0015] Figure 3 1 is a functional block diagram showing the configuration of the computing unit 40 of the sample transport device 1 .

[0016] Figure 4 It is a diagram showing the inductance characteristics with respect to the position of the coil 25 used in the specimen transport device 1 .

[0017] Figure 5Graph showing current change characteristics with respect to the position of the coil 25 .

[0018] Figure 6 1 is a diagram showing the time-series waveforms of the voltage pulse and the current of the specimen transport device 1 .

[0019] Figure 7 1 is a diagram showing the position of each current in the specimen transport device 1 with respect to the effective thrust.

[0020] Figure 8 This is a diagram explaining the influence of the switching position of the exciting coil of the sample transport device 1 on the sample transport speed.

[0021] Figure 9 It is an explanatory diagram of speed fluctuation accompanying switching of the exciting coil of the sample transport device 1 .

[0022] Figure 10 This is a diagram explaining the influence of the switching position of the exciting coil of the sample conveyor 1 on the speed variation.

[0023] Figure 11 It is an explanatory diagram of the transport speed at the second current application timing of the specimen transport device 1 .

[0024] Figure 12 1 and 2 are explanatory diagrams showing the effective thrust of the specimen transport device 1 and the movement of the specimen when the first current and the second current are applied. DETAILED DESCRIPTION

[0025] In order not to affect the analysis results, the specimen transport device needs to suppress the shaking of the liquid during the transport process. In addition, in order to transport multiple specimens, in order to prevent collisions with other specimens, it is necessary to control the stop position of the specimen (transport container) with high precision. In the electromagnetic transport device, current is applied to the coil so that the specimen can be transported in the direction of the desired transport, and the specimen is transported using the effective thrust generated by the coil. Here, in order to move the specimen to the target position, current needs to be applied to multiple coils according to the specimen position, and the effective thrust generated on the specimen is determined by the coil current, as well as the electromagnetic force (travel direction / vertical direction) and friction (μN). The electromagnetic force is determined by the positional relationship between the coil and the specimen, and the friction force is determined by the mass of the specimen and the friction coefficient of the transport surface. In other words, if the current applied to the coil and the switching position of the coil applying the current are not controlled, the fluctuation in the specimen transport speed immediately after the switching becomes larger, causing liquid shaking. Furthermore, since the coil has a magnetic resistance force (a force acting in the opposite direction of the traveling direction) near the upper portion, the specimen cannot be stopped at the target stopping position unless the coil current is controlled taking the magnetic resistance force into consideration.

[0026] This embodiment is completed to solve the above-mentioned problem. By estimating the position of the specimen based on the current information flowing through the coil winding, the position of the specimen is estimated without using a sensor for detecting the position of the specimen. In addition, by detecting the change in current that changes with the change in the inductance of the coil according to the change in the position of the specimen, the accurate position information of the specimen is obtained, thereby improving the accuracy of the position detection of the specimen. In addition, there is a liquid sloshing detector that predicts the speed change based on the speed information of the coil to which the current is applied, and controls the current amount used to suppress the liquid sloshing and the switching position of the coil to which the current is applied. In addition, in order to control the stop position with high precision, the effective thrust used to overcome the magnetic resistance of the coil is calculated, and the current amount and the switching position of the coil to which the current is applied are controlled based on the calculation result.

[0027] According to this embodiment, it is possible to suppress the shaking of the liquid during the transport while maintaining the transport efficiency, and it is possible to control the specimen stop position with high precision.

[0028] Next, embodiments of the specimen transport device according to the present invention will be described using the accompanying drawings.

[0029] First, use Figure 1 The schematic structure of the conveying device of this embodiment will be described. Figure 1 It is a schematic configuration diagram of a specimen transport device 1 according to an embodiment of the present invention. Figure 1 The outline of the specimen transport device 1 in which two coils 25 and a permanent magnet 10 move relative to each other is schematically shown.

[0030] exist Figure 1 In the embodiment, the specimen conveying device 1 includes a permanent magnet 10, a coil (coil device) 25 consisting of a cylindrical core 22 and a winding 21 wound around the outer circumference of the core 22, a drive circuit 50, a current detection unit 30, a calculation unit 40, and a power supply 55.

[0031] The permanent magnet 10 may also be a magnetic material, and the drive circuit 50 constitutes a coil drive unit. The coil drive unit may be configured to include a current detection unit 30. The calculation unit 40 constitutes the control unit of the specimen transport device 1 and controls the coil drive unit to transfer the transport container (specimen rack) 20 holding the specimen.

[0032] Figure 2 This is a schematic diagram showing a partial cross-sectional configuration example of the specimen transport device 1. The transport container 20 is configured by integrating a specimen (container) holding portion 20a with the permanent magnet 10. The transport container 20 is disposed opposite the coils 25 (25a, 25b) via the transport plane P.

[0033] Typically, the specimen transport device 1 generates electromagnetic force in the core 22 by passing current through the coils 21a and 21b of the coils 25a and 25b. This electromagnetic force controls the permanent magnet 10 disposed in the transport container 20 to move relative to the coils 25a and 25b by sliding between the plurality of coils 25a and 25b (between the coils 25 and 25) and on the transport plane P, thereby transporting the transport container 20 to a desired position.

[0034] The specimen transport device 1 requires relative positional information between the permanent magnet 10 and the coils 25a, 25b. This positional information is used to effectively apply electromagnetic force generated in the cores 22a, 22b by flowing current through the windings 21a, 21b of the coils 25a, 25b to the permanent magnet 10, and further to move the permanent magnet 10 in a target direction.

[0035] For example, assume that the permanent magnet 10 is located above (directly above) one of the two coils 25. Even if a voltage is applied to the coil 25a (winding 21a) located directly below the permanent magnet 10, no force (thrust) in the transmission direction will be generated in the permanent magnet 10. On the other hand, if a voltage is applied to the coil 25b (winding 21b) above (directly above) where there is no permanent magnet 10 (not directly below the permanent magnet 10), a force is generated that attracts the permanent magnet 10 to the coil 25b, and a force (thrust) in the transmission direction is generated. In other words, by applying a voltage to the desired coils 25a, 25b (windings 21a, 21b), a force in the transmission direction can be effectively generated on the permanent magnet 10. Moreover, by selecting the coils 25a, 25b (windings 21a, 21b) to which the voltage is applied, the direction (direction) of the force in the transmission direction can be controlled.

[0036] Next, a method for estimating the position of the specimen without using a position sensor will be described. Figure 1 When the permanent magnet 10 is positioned on the coil 25 in front of the permanent magnet 10, the magnetic flux generated by the permanent magnet 10 acts on the coil 25. Here, the magnitude of the magnetic flux acting on the coil 25 near the permanent magnet 10 is different from that on the coil 25 far away from the permanent magnet 10. In other words, the magnitude of the magnetic flux acting on the coil 25 changes depending on the relative position between the permanent magnet 10 and the coil 25.

[0037] The core 22 is made of a magnetic material, and the magnetic flux passing through the core 22 has a property that the larger the magnetic flux, the less likely it is to pass through. When a voltage is applied to the winding 21 and current flows, a magnetic flux generated by the current is generated in the core 22. Therefore, the core 22 generates a magnetic flux generated by the permanent magnet 10 and a magnetic flux generated by the current flowing through the winding 21.

[0038] Generally, when current flows through winding 21, a magnetic field is generated around it. The resulting magnetic flux is proportional to the current value. This proportionality constant is called inductance. However, in a circuit that includes a magnetic material such as core 22, the inductance changes due to the saturation characteristics of core 22.

[0039] If core 22 is saturated, the inductance changes depending on the magnitude of the magnetic flux generated in core 22. That is, the inductance of winding 21 changes depending on the magnitude of the magnetic flux of permanent magnet 10. This means that the inductance of winding 21 changes depending on the position of permanent magnet 10.

[0040] The voltage V generated in the winding 21 is expressed by equation (1).

[0041] V=-dφ / dt (1)

[0042] Here, φ is the magnetic flux and t is time. As shown in equation (1), the voltage V is expressed as the amount of change in the magnetic flux per unit time.

[0043] In addition, if the current I and the inductance L are assumed, the relationship of formula (2) is established.

[0044] dI / dt=(1 / L) × (dφ / dt) (2)

[0045] According to the above equations (1) and (2), the relationship of equation (3) holds. dI / dt=-V / L(3)

[0046] That is, when a constant voltage is applied to the winding 21, as shown in equation (3), the time differential of the supplied current I varies with the magnitude of the inductance L. This means that the manner in which the supplied current rises when the voltage is applied is different.

[0047] Therefore, when voltage is applied to the winding 21, by detecting the current flowing through the winding 21 and its flow pattern, it is possible to calculate the inductance L. In other words, if the inductance L of the winding 21, which changes according to the position of the permanent magnet 10, is detected, the position of the permanent magnet 10 that affects the inductance L can be calculated.

[0048] To this end, a drive circuit 50 is connected to the winding 21 of the coil 25, and a current detection unit 30 is provided for detecting the value of the current flowing through the winding 21. In this embodiment, a voltage is applied to the winding 21 by the drive circuit 50, and the current detection unit 30 detects the current value generated by the voltage.

[0049] The current detection unit 30 may be constituted by a series resistor, a current transformer, or a Hall current sensor, but is not limited thereto.

[0050] The drive circuit 50 is connected to a power source 55 , receives current, and supplies the current to the winding 21 of the coil 25 .

[0051] Furthermore, to obtain the thrust required to transport the transport container 20, the calculation unit 40 calculates the voltage command applied to the drive circuit 50, measures the inductance L of the coil 25 (i.e., the current change dI / dt) based on the current value detected by the current detection unit 30, and calculates the relative positional relationship between the coil 25 and the permanent magnet 10, thereby estimating the position of the permanent magnet 10 within the transport device 1. The calculation unit 40 uses the calculated positional information of the permanent magnet 10 to determine the timing for supplying the current required to transport the permanent magnet 10 (the specimen) to the coil 25, and then supplies the current from the drive circuit 50 to the appropriate coil 25.

[0052] exist Figure 3 An example of specimen position detection control at this time is shown in the block diagram of FIG. Figure 3 1 is a functional block diagram showing the configuration of the computing unit 40 of the sample transport device 1 .

[0053] like Figure 3 As shown, the operation unit 40 inputs: the order determined by the energized coil determination unit 63, the thrust (current) instruction determined according to the target value of the transmission speed calculated by the liquid slosh determination unit 65, the target switching position instruction output by the liquid slosh determination unit 65, and the position information output by the specimen position estimation unit 62, the duty cycle setting unit 60 calculates the voltage pulse, and outputs the voltage pulse to the drive circuit 50.

[0054] The duty ratio setting unit 60 calculates the on-time and off-time of the voltage pulse based on the thrust (current) command calculated by the liquid sloshing determination unit 65 , and determines the duty ratio of the voltage pulse.

[0055] The current detection unit 30 detects the current value when the voltage pulse is output to the coil 25. The current change calculation unit 61 calculates the current change (dI / dt) in the coil 25, and the specimen position estimation calculation unit 62 estimates the specimen position based on this value. Furthermore, the energized coil determination unit 63 determines the coil 25 to be energized based on the specimen's transfer target position and the specimen position estimation result. Based on this determined position and the target switching position command output by the liquid sloshing determination unit, the coil switching position calculation unit 64 switches the circuit so that the desired coil 25 is energized. The control block described here can be implemented by a computing device such as a microcomputer.

[0056] Here, refer to Figure 4 The specimen position estimating unit 62 will be described. Figure 41 is a diagram showing inductance characteristics relative to the position of the coil 25 used in the specimen transport device 1. This inductance characteristic is provided as a characteristic table of the inductance in the specimen transport device 1.

[0057] The specimen position estimating unit 62 receives the current variation (dI / dt, which corresponds to the inductance L of the coil 25) as described above and outputs the estimated position value of the transport container 20 (i.e., the specimen). For example, the specimen position estimating unit 62 sets the following parameters: Figure 4 The characteristic table of inductance with respect to the specimen position is shown.

[0058] exist Figure 4 In FIG. 1 , P3 indicates that the permanent magnet 10 is located directly above a coil 25, and P1 indicates that the permanent magnet 10 is away from the coil 25 and is located on another coil 25 that is adjacently arranged. Figure 4 The vertical axis L shows the inductance of coil 25. Observing this characteristic, it can be seen that the inductance L increases as the permanent magnet 10 changes from P3 to P1. As described above, this characteristic is the change in inductance caused by the effects of the magnetic flux generated by energizing coil 25 and the magnetic flux generated by permanent magnet 10.

[0059] Reference Figure 5 This section explains the alternative characteristics of the inductor used in the actual control logic. Figure 5 Graph showing current change characteristics with respect to the position of the coil 25 .

[0060] Although the principle of this embodiment is to use the position characteristics of the inductance L to estimate the position of the conveying container 20, in actual control logic, the current change of the coil 25 is used as input, so that the detection position estimation unit 62 can be set as Figure 5 The relationship between inductance L and current change (dI / dt) is shown in Equation (3).

[0061] Reference Figure 6 , a current waveform corresponding to a voltage waveform applied to the coil 25 for detecting the position of the transport container 20 in the specimen transport device 1 will be described. Figure 6 1 is a diagram showing the time-series waveforms of the voltage pulse and the current of the specimen transport device 1 .

[0062] Figure 6 The current value relative to the voltage pulse is represented by calculating the current change (dI / dt) based on the difference between the current value (maximum value) at the time the voltage pulse ends and the current value (minimum value) at the time the voltage pulse ends. The specimen position estimating unit 62 estimates the specimen position (the position of the transport container 20) over time by sequentially calculating this current change (dI / dt).

[0063] Next, explain Figure 3 The liquid slosh determination unit 65 is shown. The liquid slosh determination unit 65 determines the liquid slosh of the specimen based on the specimen's velocity fluctuations. The liquid slosh determination unit 65 determines the liquid slosh and outputs a thrust (current) command that sufficiently suppresses the liquid slosh to the duty cycle setting unit 60. The switching position of the current application coil at that time, i.e., the target switching position that determines the specimen's position at which the current application coil is switched, is output to the coil switching position calculation unit 64. Here, to accurately control the specimen's stopping position, the command current and target switching position are each set to two stages.

[0064] Reference Figure 7 The characteristics of the effective thrust relative to the specimen position are described. Figure 7 1 is a diagram showing the position of each current in the specimen transport device 1 with respect to the effective thrust.

[0065] The effective thrust Feff is expressed by formula (4).

[0066] Feff=Fx-μ(mg+Fz)(4)

[0067] Here, Fx is a force generated in the coil 25 and acting in a horizontal direction relative to the conveying plane P, Fz is a force generated in the coil 25 and acting in a vertical direction relative to the conveying plane P, m is the specimen mass, and μ is the friction coefficient.

[0068] Figure 7 The characteristics show the characteristics when current is applied (excited) to the coil 3. Figure 7 d is the distance between the coils. When the specimen is located at coil 1, that is, 2 pitches (2d) away, Fx has almost no effect, and the friction force of the deadweight component and Fz act in the direction of decelerating the specimen. When the specimen is located at coil 2, that is, 1 pitch (d) away, due to the increase in Fx, a force acts in the direction of accelerating the specimen. Thereafter, as the specimen approaches coil 3, the acceleration force gradually increases. Although it depends on the characteristics of the coils, the effective thrust reaches its maximum when the specimen reaches the middle point between coils 2 and 3, and then decreases as the specimen approaches further. Furthermore, if the specimen approaches and reaches near the top of coil 3, the magnetic resistance of coil 3 acts, Fz increases, and therefore a force acts in the direction of decelerating the specimen. In addition, since Fx and Fz shown in formula (4) increase with the amount of current, the larger the amount of current, the greater the actual thrust.

[0069] Here, the first current is set to be mainly in the period from when the excitation coil is just switched from coil 2 to coil 3 to when the excitation coil is in the stop position ( Figure 7The first current is the current applied to the specimen from the time it approaches the predetermined position until the specimen stops. Figure 7 The current corresponding to the small current indicated by the dotted line is applied to the coil 3. On the other hand, since the second current is a current for overcoming the deceleration force by the magnetic resistance so that the specimen stops at the stopping target, Figure 7 A current corresponding to a large current indicated by a solid line is applied to the coil 3 .

[0070] As described above, in this embodiment, the computing unit (control unit) 40 sets a first interval, near the stop coil at the stop position closest to the specimen, on the side away from the stop coil, and a second interval, closer to the stop coil than the first interval. Furthermore, when the specimen is present in the first interval, the first current is set as the current flowing through the stop coil, and when the specimen is present in the second interval, the second current is set as the current flowing through the stop coil. In this embodiment, the stop coil at the stop position closest to the specimen is coil 3, and the second interval includes the stop position and is set continuously within the first interval.

[0071] Furthermore, based on the determination information of the liquid sloshing determination unit 65 , the first current is set to a magnitude that suppresses the sloshing of the liquid of the specimen, and the second current is set to a current value greater than the first current.

[0072] The first current and the second current are generated according to the duty ratio of the voltage pulse set by the duty ratio setting unit 60 .

[0073] Next, refer to Figure 8 Describe the switching position of the excitation coil. Figure 8 This is a diagram explaining the influence of the switching position of the exciting coil of the sample transport device 1 on the sample transport speed.

[0074] exist Figure 8 In the figure, the horizontal axis shows the switching position of the coil applying current, and the vertical axis shows the speed of the specimen when it reaches the same switching position after the excitation coil is switched. The switching position here refers to the distance between the specimen and the excitation coil immediately before the current application coil is switched.

[0075] When the switching position is large, that is, the distance between the excitation coil and the specimen is large, the excitation coil is switched. In the region where the effective thrust is large and acceleration is performed ( Figure 7 The excitation coil is switched (near the middle of coils 2 and 3 in the image). Switching the excitation coil increases the distance between the specimen and the excitation coil by one more pitch, thus acting to decelerate the specimen.

[0076] On the other hand, when the excitation coils are switched when the switching position is small, that is, when the distance between the excitation coils and the specimen is close, the excitation coils are switched after sufficient acceleration in the area where the effective thrust is large and acceleration is occurring. While it is common for the distance from the excitation coils to increase by one pitch with each excitation coil switch, since the excitation coils are switched while the specimen is close, the distance from the excitation coils becomes relatively close, and the force acting in the direction of decelerating the specimen decreases accordingly.

[0077] Here, in order to control the stop position with high precision, which is the object of the present invention, the conveying container 20 needs to be sufficiently decelerated, and therefore the switching position needs to be increased.

[0078] then, Figure 9 The speed change waveform when the coils applying current are switched is shown in the figure. Figure 7 The coil 3 shown is applied with a smaller current than that of the coil 2 in order to decelerate it. If the coil to which the current is applied is switched from the coil 2 to the coil 3, the distance between the specimen and the coil 3 at the moment of switching is away from 1 pitch, so the effective thrust is reduced and the acceleration of the specimen transmission is also reduced. In order to manage the specimen transmission by speed, the speed gradient before and after the current application coil is switched is set as speed change 1 and speed change 2. It can be seen that the maximum values ​​of speed change 1 and speed change 2 are correlated with the amount of liquid shaking during transmission, and they are used for liquid shaking determination by the liquid shaking determination unit 65. In addition, it is not limited to the maximum value. For example, the difference between speed change 1 (positive value) and speed change 2 (negative value) can be used.

[0079] Next, Figure 10 The horizontal axis shows the switching position, and the vertical axis shows the speed change. Figure 10 The correlation between the switching position and the speed change shown in Figure 8 The correlation between the switching position and the speed shown is an opposite characteristic. This means that the speed after switching is large, the change in actual thrust is small, and liquid sloshing is unlikely to occur. That is, since there is a trade-off between the distance of the switching position and the liquid sloshing, in order to control the switching position so that the specimen speed can be sufficiently slowed down while suppressing the liquid sloshing, the liquid sloshing determination unit 65 determines whether the liquid sloshing is qualified. Here, the pass / fail judgment value of the liquid sloshing can be obtained, for example, using data obtained by obtaining the amount of liquid sloshing when the switching position is actually changed through a camera, etc. The switching position is controlled to meet the pass / fail judgment of the liquid sloshing and to slow down the specimen speed as much as possible. As described above, the liquid sloshing determination unit 65 uses the effective thrust characteristics of the coil 25 to determine the liquid sloshing.

[0080] Next, use Figure 11 A control method when switching from the first current to the second current is described. Figure 11 It is an explanatory diagram of the transport speed of the sample transport device 1 at the application timing of the second current. Figure 11 The characteristics of the position relative to the effective thrust and the positional relationship between the coil and the specimen (transport container 20 ) are shown.

[0081] Let the speed of the specimen just before switching to the second current be v2, and the distance between the coil 3 and the specimen at this time be x1. In order to make the specimen stop directly above the coil 3, that is, the speed is set to 0, the following relationship holds according to the relationship between kinetic energy and work.

[0082] 0-(1 / 2)mv2 2 =Feff·x1(5)

[0083] Using formula (5), the switching position is determined based on the speed information and effective thrust of the specimen. In addition, as in the case of applying the first current, the switching position is determined based on whether the liquid sloshing is qualified. In addition, for example, the specimen speed can be obtained by differentiating the position information input from the specimen position estimation unit 62. Basically, it is a premise that the speed is sufficiently decelerated within the interval in which the first current is applied. However, for example, when the friction coefficient is smaller than the assumed case due to deterioration of the conveying surface P, resulting in a decrease in friction and an increase in effective thrust, it can be considered that the conveying speed of the specimen becomes faster than the assumed case. Therefore, the target thrust is calculated successively based on the position and speed information of the specimen. When the conveying speed is faster than the assumed case, the stop position accuracy is ensured by reducing the current value.

[0084] Figure 12 1 and 2 are explanatory diagrams showing the effective thrust of the specimen transport device 1 and the movement of the specimen when the first current and the second current are applied.

[0085] During the first current interval, the excitation coil is switched at a switching position where no liquid sloshing occurs and a deceleration force is achieved. Furthermore, when the specimen is sufficiently close to the stop position (coil 3), the position for switching from the first current to the second current is determined based on the correlation between kinetic energy and work. The first current is smaller than the second current, and the second current is larger than the first current.

[0086] As described above, in this embodiment, the specimen transport device 1 includes: a transport container 20 having a magnet 10 or a magnetic body and a holding portion 20a for holding the specimen; a plurality of coils 25 for transporting the transport container 20; a coil driving portion 50 for applying voltage to the plurality of coils 25; and a control portion 40 for controlling the coil driving portion 50. The control portion 40 includes a liquid sloshing determination portion 65 for determining liquid sloshing of the specimen based on a change in the speed of the specimen. The control portion 40 sets a first interval S1 on a side away from the stop coil 3 near the stop position closest to the specimen, and sets a second interval S2 on a side closer to the stop coil 3 than the first interval S1. When the specimen is present in the first interval S1, a first current is set as the current supplied to the stop coil 3, and when the specimen is present in the second interval S2, a second current is set as the current supplied to the stop coil 3. The first current is set to a magnitude that suppresses liquid sloshing of the specimen based on determination information from the liquid sloshing determination portion 65, and the second current is set to a current value greater than the first current.

[0087] In this case, it is preferable to set the first current so that the liquid sloshing of the specimen is suppressed to Figure 10 The liquid sloshing is qualified or not. The size of the specified liquid sloshing is used to judge whether the liquid sloshing is qualified or not.

[0088] As described above, in this embodiment, when the liquid does not slosh and a decrease in the conveying speed is foreseen, the first current is supplied to the stop coil at the stop position closest to the specimen. When the kinetic energy and work of the specimen reach a balance, the second current is supplied to the stop coil at the stop position closest to the specimen. In other words, the operation unit (control unit) 40 supplies the first current to the stop coil at the stop position closest to the specimen when the liquid does not slosh and a decrease in the conveying speed is foreseen. When the kinetic energy and work of the specimen reach a balance, the operation unit (control unit) 40 supplies the second current to the stop coil at the stop position closest to the specimen.

[0089] By adopting the above-mentioned structure, the specimen stopping position can be controlled with high precision while suppressing the shaking of the liquid during specimen transportation.

[0090] The present invention is not limited to the above-described embodiments and includes various variations. For example, the above-described embodiments are provided for ease of understanding of the present invention and are not necessarily limited to all structures. Furthermore, some structures of the embodiments may be added, deleted, or replaced with other structures.

[0091] Description of labels

[0092] 1... specimen transport device, 3... stop coil, 10... permanent magnet, 20... transport container, 20a... holding unit, 25... coil, 40... calculation unit (control unit), 50... drive circuit (coil drive unit), 65... liquid sloshing determination unit, S1... first interval, S2... second interval.

Claims

1. A specimen conveying device, comprising: a transport container having a magnet or a magnetic body and a holding portion for holding a specimen; a plurality of coils for conveying the conveying container; a coil driving unit for applying voltage to the plurality of coils; and a control unit for controlling the coil driving unit, characterized in that: The control unit includes a liquid sloshing determination unit for determining liquid sloshing of the specimen based on a change in the velocity of the specimen. The control unit sets a first interval on a side away from the stop coil near the stop position closest to the specimen, and sets a second interval on a side closer to the stop coil than the first interval, and sets a first current as the current for energizing the stop coil when the specimen exists in the first interval, and sets a second current as the current for energizing the stop coil when the specimen exists in the second interval. The first current is set to a magnitude that suppresses liquid sloshing of the specimen based on determination information from the liquid sloshing determination unit. The second current is set to a current value greater than the first current.

2. The specimen conveying device according to claim 1, wherein The liquid sloshing determination unit determines liquid sloshing using effective thrust characteristics of the coil.

3. The specimen conveying device according to claim 1, wherein The first current is supplied to the stop coil at a timing when liquid sloshing does not occur and a reduction in the conveying speed is expected.

4. The specimen conveying device according to claim 1, wherein The second current is supplied to the stop coil at a timing when the kinetic energy and work of the specimen reach equilibrium.

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