JP2007278978A - Dispensing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dispensing apparatus capable of improving the dispensing accuracy. <P>SOLUTION: The dispensing apparatus comprises pipes 13 and 16 with tips connected to a probe 19 and with fluid moving and a valve 25 for permitting and regulating the movement of the fluid in the pipes by opening or closing based on an output driving signal. The dispensing apparatus sucks a liquid sample from the probe 19 by moving the fluid in the pipes, and delivers and dispenses the sucked liquid sample. The dispensing apparatus comprises delay time calculating means 39 and 40 for calculating the operation delay time of the valve 25 by measuring time from output of the driving signal to varying of the pressure in the pipes, and valve controlling means 41 and 32 for controlling the operation time of the valve 25 based on the operation delay time calculated by the delay time calculating means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a dispensing apparatus, and more particularly, to an improvement of a dispensing apparatus that sucks a liquid sample containing a specimen or a reagent and discharges the sucked liquid sample to perform dispensing.

  2. Description of the Related Art Conventionally, for example, a dispensing apparatus used when dispensing a liquid sample containing a specimen or a reagent is moved from a probe connected to the tip of the pipe by moving cleaning water filling the pipe under a constant pressure. The liquid sample is sucked and dispensed by discharging the sucked liquid sample to a predetermined position.

  In such a dispensing device, a solenoid valve is provided at the tip end region of the pipe, that is, upstream of the probe in the pipe, and the solenoid valve is opened / closed at high speed or energized for a certain time to open the solenoid valve. Thus, the dispensing amount of the liquid sample is controlled (see, for example, Patent Document 1 and Patent Document 2).

JP 2004-61153 A JP 2004-89849 A

  By the way, when a drive signal for instructing an opening / closing operation is output, the solenoid valve opens or closes after the output time of the drive signal. Generally, a delay time when the closing operation is performed (hereinafter also referred to as a closing operation delay time) is different. The opening operation delay time and the closing operation delay time vary depending on individual differences of solenoid valves, changes with time, ambient temperature, control circuit, and the like.

  Therefore, as in the conventional dispensing device as described above, the dispensing amount of the liquid sample can be controlled by opening and closing the solenoid valve at high speed or opening the solenoid valve by energizing for a certain period of time. The actual opening time of the solenoid valve fluctuates due to the individual differences of solenoid valves, changes over time, ambient temperature, control circuit, etc., and this causes the dispensing volume to fluctuate, resulting in dispensing accuracy There was a problem that it was not high enough.

  An object of this invention is to provide the dispensing apparatus which can aim at the improvement of dispensing precision in view of the said situation.

  In order to achieve the above object, a dispensing apparatus according to claim 1 of the present invention is provided with a tip connected to a probe, a flow path through which fluid moves, and a tip region of the flow path. A valve that permits and regulates movement of the fluid in the flow path by opening and closing based on the output drive signal, and moving the fluid in the flow path to remove the liquid sample from the probe In a dispensing apparatus that performs suction by dispensing the sucked liquid sample and performing dispensing, the operation of the valve is measured by measuring the time from when the drive signal is output until the pressure in the flow path changes. A delay time calculating means for calculating a delay time, and a valve control means for controlling the operation time of the valve based on the operation delay time calculated by the delay time calculating means.

  The dispensing device according to claim 2 of the present invention is the dispensing device according to claim 1, wherein the delay time calculating means closes the valve so that the flow path has a positive pressure. The valve opening operation delay time is calculated by measuring the time from the output of the drive signal for opening the valve until the pressure in the flow path decreases, while the valve is opened to When the inside of the passage is pressurized, the valve closing operation delay time is measured by measuring the time from when the drive signal for closing the valve is output until the pressure in the passage increases. Is calculated.

  The dispensing apparatus according to claim 3 of the present invention has a tip connected to the probe, a flow path through which the fluid moves, and a tip region of the flow path. A valve that allows and regulates the movement of the fluid in the flow path, and moves the fluid in the flow path, thereby sucking the liquid sample from the probe and discharging the sucked liquid sample for dispensing. A fluid suction means for sucking a fluid in the flow path and bringing the flow path into a negative pressure state when air is introduced into the flow path and the valve is closed in the dispensing device to be performed; When the fluid suction means places the inside of the channel in a negative pressure state, the valve is opened for a predetermined time, the liquid sample is allowed to flow into the channel, and the pressure in the channel is measured. The correlation between the pressure in the flow path and the flow rate of the liquid sample. The flow rate of the liquid sample is calculated from the first calculation means for calculating the correlation, the correlation calculated by the first calculation means, and the measured pressure in the flow path, and the flow rate of the liquid sample is determined in advance. Second calculating means for calculating the valve opening time from the desired discharge amount, and valve opening operation control means for controlling the valve opening operation according to the valve opening time calculated by the second calculating means. It is characterized by having.

  According to the first aspect of the present invention, the valve operation delay time is calculated by measuring the time from when the drive signal is output until the pressure in the flow path changes through the delay time calculation means. In addition, since the valve operation time is controlled based on the operation delay time calculated by the delay time calculation means through the valve control means, a desired amount of liquid sample can be accurately discharged, and individual differences in the valve and time There is no fear that the dispensing amount will fluctuate due to the influence of change, ambient temperature, control circuit and the like. Therefore, it is possible to improve the dispensing accuracy.

  According to the third aspect of the present invention, when air is introduced into the flow path to close the valve, the fluid in the flow path is sucked through the fluid suction means to When the pressure in the flow path is made negative by the fluid suction means, the valve is opened for a predetermined time, and a liquid sample is allowed to flow into the flow path to measure the pressure in the flow path. Thus, the correlation between the pressure in the flow path and the flow rate of the liquid sample is calculated through the first calculation means, and the correlation calculated by the first calculation means and the measurement in the flow path are measured through the second calculation means. The flow rate of the liquid sample is calculated from the pressure, the valve opening time is calculated from the flow rate of the liquid sample and a predetermined desired discharge amount, and the valve opening operation control means follows the calculated valve opening time. Controls the opening operation of the valve, so that the liquid sample is discharged accurately. Rukoto can, viscosity of the liquid sample, there is no fear that dispense volume may fluctuate due to the influence of the probe diameters. Therefore, it is possible to improve the dispensing accuracy.

  Exemplary embodiments of a dispensing device according to the present invention will be described below in detail with reference to the accompanying drawings.

<Embodiment 1>
FIG. 1 is a schematic diagram schematically showing the configuration of the dispensing apparatus in the first embodiment of the present invention. The dispensing apparatus in FIG. 1 performs dispensing by, for example, sucking a liquid sample containing a specimen or a reagent and discharging the sucked liquid sample. Such a dispensing apparatus includes a dispensing unit 10 and a control unit 30.

  The dispensing unit 10 includes a washing water tank 11, a three-way valve 14, an air pump 20, a first pressure sensor 22, a second pressure sensor 24, and a valve 25.

  The washing water tank 11 is a tank that stores washing water. The opening of the washing water tank 11 has a stopper 12 for making the inside airtight. Further, a cleaning water introduction pipe 13 is connected to the cleaning water tank 11. More specifically, the cleaning water introduction pipe 13 passes through a through hole (not shown) of the stopper 12 in a manner that keeps the inside of the cleaning water tank 11 airtight, and the base end of the cleaning water introduction pipe 13 is stored. It is connected to the washing water tank 11 in a state immersed in the washing water. Further, the tip of the cleaning water introduction pipe 13 is connected to the three-way valve 14.

  The three-way valve 14 is a valve element that is connected to the cleaning water introduction pipe 13 and to each of the syringe pipe 15 and the probe pipe 16. More specifically, the three-way valve 14 has an A end connected to the distal end of the cleaning water introduction pipe 13, a B end connected to the distal end of the syringe pipe 15, and a C end connected independently to the proximal end of the probe pipe 16. By outputting a signal from the control unit 30, two selected pipes among these pipes are opened. The syringe pipe 15 is a pipe having a syringe pump 17 disposed at the proximal end. The syringe pump 17 houses a piston 18 therein. The probe pipe 16 is provided with a probe 19 serving as a dispensing nozzle at the tip. The probe 19 is arranged so as to be movable in the horizontal direction and the vertical direction by a probe driving unit (not shown).

  The air pump 20 is for sending air into the cleaning water tank 11 through the air supply pipe 21. Here, the air supply pipe 21 passes through a through hole (not shown) of the stopper 12 in a manner to keep the inside of the washing water tank 11 airtight, and one end faces the gas phase region inside the washing water tank 11. It is connected to the washing water tank 11.

  The first pressure sensor 22 is a detection means for detecting the pressure inside the wash water tank 11 through the detection pipe 23. Here, the detection pipe 23 passes through a through hole (not shown) of the stopper 12 in a manner to keep the inside of the washing water tank 11 airtight, and one end faces the gas phase region inside the washing water tank 11. The washing water tank 11 is connected. The second pressure sensor 24 is disposed in the probe pipe 16 and is a detection means for detecting the pressure inside the probe pipe 16.

  The valve 25 is disposed at the tip region of the probe pipe 16, that is, between the probe 19 and the second pressure sensor 24, and opens and closes to allow fluid (cleaning water, liquid sample, etc.) in the probe pipe 16. Movement is permitted and restricted.

  FIG. 2 is a block diagram schematically showing the configuration of the control unit in FIG. The control unit 30 includes a main control unit 31, a valve drive signal output unit 32, an air pump drive processing unit 33, a syringe pump drive processing unit 34, a control signal output unit 35, a first pressure sensor detection processing unit 36, and a second pressure sensor. A detection processing unit 37, a time measurement unit 38, an opening operation delay time calculation unit 39, a closing operation delay time calculation unit 40, and a valve drive correction unit 41 are provided.

  The main control unit 31 performs overall control of the operation of the control unit 30 based on data and programs stored in a memory 42 such as a ROM or RAM.

  The valve drive signal output unit 32 outputs a valve drive signal to the valve 25. When the valve drive signal is turned on, the valve 25 is opened, while when the valve drive signal is turned off. The valve 25 is closed.

  The air pump drive processing unit 33 outputs various signals to the air pump 20 to drive the air pump 20. When the air pump drive signal is output, the air pump drive processing unit 33 drives the air pump 20 while the air pump 20 is driven. When the pump stop signal is output, the driving of the air pump 20 is stopped.

  The syringe pump drive processing unit 34 outputs various signals to the syringe pump 17 to perform drive processing of the syringe pump 17. When the syringe pump drive signal is output, the syringe pump 17 is driven while the syringe pump 17 is driven. When the pump stop signal is output, the driving of the syringe pump 17 is stopped.

  The control signal output unit 35 outputs various control signals to the three-way valve 14. More specifically, when the first control signal is output, the three-way valve 14 causes the cleaning water introduction pipe 13 and the probe pipe 16 to be opened, while when the second control signal is output, the three-way valve 14 makes the syringe pipe 15 and the probe pipe 16 open.

  The first pressure sensor detection processing unit 36 detects and processes the pressure value detected by the first pressure sensor 22. The second pressure sensor detection processing unit 37 detects and processes the pressure value detected by the second pressure sensor 24. The time measuring unit 38 measures time.

  The opening operation delay time calculating unit 39 calculates the delay time of the opening operation of the valve 25 based on the time measured by the time measuring unit 38, as will be described in detail later. The closing operation delay time calculation unit 40 calculates the delay time of the closing operation of the valve 25 based on the time measured by the time measurement unit 38, as will be described in detail later.

  The valve drive correcting unit 41 corrects the time for opening the valve 25 based on the opening operation delay time calculated by the opening operation delay time calculating unit 39 and the closing operation delay time calculated by the closing operation delay time calculating unit 40. To do. More specifically, the valve drive through the valve drive signal output unit 32 is based on the opening operation delay time calculated by the opening operation delay time calculation unit 39 and the closing operation delay time calculated by the closing operation delay time calculation unit 40. The time for turning on the signal is corrected.

  The dispensing apparatus having the above configuration performs the following operation. First, the dispensing device measures the operation delay time of the valve 25. FIG. 3 is a flowchart showing the processing contents of the main controller of the control unit in FIG. 2, and FIG. 4 is a time chart showing the measurement of the valve operation delay time. The measurement of the operation delay time of the valve 25 by the dispensing device will be described with reference to FIGS. 3 and 4 as appropriate. As a premise for explanation, the main control unit 31 of the control unit 30 outputs a first control signal to the three-way valve 14 through the control signal output unit 35, and the cleaning water introduction pipe 13 and the probe pipe 16 are in communication with each other. That is, it is assumed that the A end and the C end are open.

  The main control unit 31 of the control unit 30 turns off the valve drive signal through the valve drive signal output unit 32 and outputs an air pump drive signal through the air pump drive processing unit 33 (steps S101 and S102). Thus, the valve 25 is closed by turning off the valve drive signal, and the air pump 20 is driven by outputting the air pump drive signal (time point t1).

  The main control unit 31 detects and processes the pressure value detected by the first pressure sensor 22 through the first pressure sensor detection processing unit 36, and the pressure inside the wash water tank 11 is determined in advance, that is, positive pressure. It is determined whether or not it is in a state (step S103). Here, if the inside of the washing water tank 11 is in a positive pressure state, the inside of the washing water introduction pipe 13 and the probe pipe 16 communicating with the inside is in an airtight state, so that the inside is similarly in a positive pressure state. When it is determined that the inside of the washing water tank 11 is in the positive pressure state, the main control unit 31 outputs an air pump stop signal through the air pump drive processing unit 33 (step S104). Thereby, the drive of the air pump 20 is stopped (time t2).

  At time t3, the main control unit 31 turns on the valve drive signal through the valve drive signal output unit 32 and starts measuring time through the time measurement unit 38 (steps S105 and S106). At this time, the main control unit 31 detects the pressure value detected by the second pressure sensor 24 through the second pressure sensor detection processing unit 37, and determines whether or not the pressure in the pipe has decreased (step S107). ). If it is determined that the pressure has decreased (time t4), the main control unit 31 ends the time measurement through the time measurement unit 38 (step S108).

  Thereafter, the main control unit 31 calculates the opening operation delay time (time point t4−time point t3) of the valve 25 from the time measured by the time measurement unit 38 through the opening operation delay time calculation unit 39 (step S109).

  The main control unit 31 outputs an air pump drive signal through the air pump drive processing unit 33 (step S110). Thus, the air pump 20 is driven by outputting the air pump drive signal (time t5).

  At time t6 after outputting the air pump drive signal, the main control unit 31 turns off the valve drive signal through the valve drive signal output unit 32 and starts measuring time through the time measurement unit 38 (step S111). , Step S112). At this time, the main control unit 31 detects and processes the pressure value detected by the second pressure sensor 24 through the second pressure sensor detection processing unit 37, and determines whether or not the pressure in the pipe has increased (step S113). ). If it is determined that the pressure has increased (time t7), the main control unit 31 ends the time measurement through the time measurement unit 38 (step S114).

  Thereafter, the main control unit 31 calculates the closing operation delay time (time point t7−time point t6) of the valve 25 from the time measured by the time measuring unit 38 through the closing operation delay time calculation unit 40 (step S115). Terminate the process. Here, the opening operation delay time of the valve 25 calculated in step S109 and the closing operation delay time of the valve 25 calculated in step S115 are stored in the memory 42, respectively.

  After measuring the operation delay time of the valve 25 as described above, the dispensing device performs the following dispensing operation. First, the probe 19 is moved to the cleaning position by the probe driving unit.

  After being moved to the cleaning position, the main control unit 31 of the control unit 30 causes the main control unit 31 of the control unit 30 to turn on the valve drive signal through the valve drive signal output unit 32, and the control signal output unit 35. The first control signal is output through As a result, the valve 25 is opened, and the three-way valve 14 is brought into a state where the cleaning water introduction pipe 13 and the probe pipe 16 are communicated, that is, a state where the A end and the C end are opened. Thereafter, the main control unit 31 of the control unit 30 drives the air pump 20 by outputting an air pump drive signal through the air pump drive processing unit 33. As a result, the inside of the cleaning water tank 11 is pressurized, and the cleaning water is discharged from the probe 19 by moving through the cleaning water introduction pipe 13 and the probe pipe 16. In this way, the cleaning water in the cleaning water tank 11 is discharged from the probe 19 so that the probe 19 is cleaned. After the cleaning water is discharged from the probe 19, the control unit 30 (main control unit 31) closes the valve 25 by turning off the valve drive signal while leaving a predetermined amount of air layer at the tip of the probe 19. Let Thereby, the inside of piping can be made into the state filled with the washing water, leaving a predetermined amount of air layer at the tip of the probe 19.

  Next, the probe drive unit moves the probe 19 to a position where the sample container (sample cup) is arranged, and after moving the probe 19, the probe 19 is moved downward to immerse the tip of the probe 19 in the liquid sample in the sample container. Let After the tip of the probe 19 is immersed in the liquid sample, the main control unit 31 of the control unit 30 turns on the valve drive signal through the valve drive signal output unit 32 and performs the second control through the control signal output unit 35. Output a signal. Thus, the valve 25 is opened, and the three-way valve 14 is brought into a state where the syringe pipe 15 and the probe pipe 16 are in communication, that is, a state where the B end and the C end are opened. At this time, the control unit 30 (main control unit 31) outputs a syringe pump drive signal through the syringe pump drive processing unit 34. As a result, the syringe pump 17 can be driven to suck a predetermined amount of liquid sample into the probe 19. At this time, since the liquid sample is sucked with the air layer interposed between the cleaning water and the cleaning water, the liquid sample is not mixed with the cleaning water.

  After sucking a predetermined amount of the liquid sample, the probe 19 is moved up by the probe driving unit and moved to the position where the reaction vessel is arranged. Thereafter, the probe 19 is moved downward again by the probe driving unit.

  After the probe 19 is moved downward again, the control unit 30 (main control unit 31) outputs the first control signal through the control signal output unit 35. As a result, the three-way valve 14 is brought into a state where the cleaning water introduction pipe 13 and the probe pipe 16 communicate with each other. By the way, the internal pressure of the washing water tank 11 is always detected by the first pressure sensor 22, and the air pump 20 is driven as necessary so that the detected pressure is constant. That is, the main control unit 31 of the control unit 30 detects and processes the pressure value detected by the first pressure sensor 22 through the first pressure sensor detection processing unit 36 and outputs an air pump drive signal through the air pump drive processing unit 33. Alternatively, the pressure in the washing water tank 11 is made constant by outputting an air pump stop signal.

  On the other hand, the main control unit 31 of the control unit 30 passes the valve drive correction unit 41 through the opening operation delay time calculated by the opening operation delay time calculation unit 39 and the closing operation delay calculated by the closing operation delay time calculation unit 40. Based on the time, the time for turning on the valve drive signal through the valve drive signal output unit 32 is corrected. More specifically, the main control unit 31 uses the valve drive correction unit 41 to set the desired opening time of the valve 25 stored in the memory 42 in advance and the valve 25 stored in the memory 42 as described above. The actual time for turning on the valve drive signal through the valve drive signal output unit 32 is corrected from the open operation delay time and the close operation delay time. The actual time T for turning on the valve driving signal is expressed by the following equation (1), which is a predetermined desired opening time s1, opening operation delay time s2 of the valve 25, and closing operation delay time s3 of the valve 25. ).

  Formula (1) T = s1 + s2-s3

  After correcting the actual time for turning on the valve drive signal through the valve drive correction unit 41, the main control unit 31 outputs the valve drive signal through the valve drive signal output unit 32 for the time corrected by the valve drive correction unit 41. Turn on. Accordingly, the valve 25 can be opened for a desired time in consideration of the opening operation delay time and the closing operation delay time.

  As described above, since the internal pressure of the cleaning water tank 11 is kept constant, the liquid sample is discharged from the probe 19 at a constant flow rate when the valve 25 is opened. Therefore, when the valve 25 is opened for a desired time, a desired amount of liquid sample can be accurately discharged.

  After completion of the discharge of the liquid sample into the reaction container, the probe drive unit moves the probe 19 to a position where another reaction container is arranged, and repeats the above-described discharge of the liquid sample to perform a dispensing operation.

  As described above, in the dispensing device according to Embodiment 1 of the present invention, the main control unit 31, the opening operation delay time calculation unit 39, and the closing operation delay time calculation unit 40 constitute a delay time calculation unit, and the main control unit The unit 31, the valve drive signal output unit 32, and the valve drive correction unit 41 constitute valve control means. According to such a dispensing apparatus, the opening operation delay time and the closing operation delay time of the valve 25 are determined by measuring the time from when the valve drive signal is output until the pressure in the pipe changes. Since the operation time of the valve 25 is controlled by correcting the actual opening time of the valve 25 based on the calculated opening operation delay time and the calculated closing operation delay time, a desired amount of liquid sample can be discharged accurately. Therefore, there is no possibility that the dispensing amount fluctuates due to individual differences of valve 25, changes with time, ambient temperature, control circuit, and the like. Therefore, the dispensing accuracy can be improved.

<Embodiment 2>
FIG. 5 is a schematic diagram schematically showing the configuration of the dispensing apparatus in the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to what has the same structure as the dispensing apparatus which concerns on Embodiment 1 mentioned above, and the description is abbreviate | omitted.

  The dispensing apparatus in FIG. 5 performs dispensing by, for example, sucking a liquid sample containing a specimen or a reagent and discharging the sucked liquid sample. Such a dispensing apparatus includes a dispensing unit 10 ′ and a control unit 50.

  The dispensing unit 10 ′ has substantially the same configuration as the dispensing unit 10 according to the first embodiment described above, except that the fan 26 is provided. The fan 26 is for heating the fluid inside the probe pipe 16 to keep the temperature constant.

  FIG. 6 is a block diagram schematically showing the configuration of the control unit in FIG. The control unit 50 includes a main control unit 51, a valve drive signal output unit 52, an air pump drive processing unit 53, a syringe pump drive processing unit 54, a control signal output unit 55, a first pressure sensor detection processing unit 56, and a second pressure sensor. A detection processing unit 57, a time measurement unit 58, a pressure-flow rate calculation unit (first calculation unit) 59, and a valve opening time calculation unit (second calculation unit) 60 are provided.

  The main control unit 51 performs overall control of the operation of the control unit 50 based on data and programs stored in a memory 61 such as a ROM or RAM.

  The valve drive signal output unit 52 outputs a valve drive signal to the valve 25. When the valve drive signal is turned on, the valve 25 is opened, while when the valve drive signal is turned off. The valve 25 is closed.

  The air pump drive processing unit 53 outputs various signals to the air pump 20 to drive the air pump 20, and when the air pump drive signal is output, the air pump 20 is driven while the air pump 20 is driven. When the pump stop signal is output, the driving of the air pump 20 is stopped.

  The syringe pump drive processing unit 54 outputs various signals to the syringe pump 17 to drive the syringe pump 17. When the syringe pump drive signal is output, the syringe pump 17 is driven while the syringe pump 17 is driven. When the pump stop signal is output, the driving of the syringe pump 17 is stopped.

  The control signal output unit 55 outputs various control signals to the three-way valve 14. More specifically, when the first control signal is output, the three-way valve 14 causes the cleaning water introduction pipe 13 and the probe pipe 16 to be opened, while when the second control signal is output, the three-way valve 14 makes the syringe pipe 15 and the probe pipe 16 open.

  The first pressure sensor detection processing unit 56 detects and processes the pressure value detected by the first pressure sensor 22. The second pressure sensor detection processing unit 57 detects and processes the pressure value detected by the second pressure sensor 24. The time measuring unit 58 measures time.

  The pressure-flow rate calculation unit 59 calculates the correlation between the pressure in the pipe and the flow rate of the liquid sample, details of which will be described later.

  The valve opening time calculation unit 60 calculates the flow rate of the liquid sample from the correlation calculated by the pressure-flow rate calculation unit 59 and the measured pressure in the pipe, and the details will be described later. The opening time of the valve 25 is calculated from a predetermined desired discharge amount stored in the memory 61.

  The dispensing apparatus having the above configuration performs the following operation. First, the probe 19 is moved to the cleaning position by the probe driving unit.

  After moving to the cleaning position, the main control unit 51 of the control unit 50 causes the main control unit 51 of the control unit 50 to turn on the valve drive signal through the valve drive signal output unit 52, and also to control the signal output unit 55. The first control signal is output through As a result, the valve 25 is opened, and the three-way valve 14 is brought into a state where the cleaning water introduction pipe 13 and the probe pipe 16 are communicated, that is, a state where the A end and the C end are opened. Thereafter, the main control unit 51 of the control unit 50 drives the air pump 20 by outputting an air pump drive signal through the air pump drive processing unit 53. As a result, the inside of the cleaning water tank 11 is pressurized, and the cleaning water is discharged from the probe 19 by moving through the cleaning water introduction pipe 13 and the probe pipe 16. In this way, the cleaning water in the cleaning water tank 11 is discharged from the probe 19 so that the probe 19 is cleaned. After the cleaning water is discharged from the probe 19, the control unit 50 (main control unit 51) turns off the valve drive signal and closes the valve 25. Thereby, the inside of piping can be made into the state filled with washing water.

  Next, the probe drive unit moves the probe 19 to a position where the sample container (sample cup) is arranged. FIG. 7 is a flowchart showing the processing contents of the main control unit of the control unit in FIG. Using FIG. 7 as appropriate, the operation at the sample container arrangement position by the dispensing device will be described.

  After moving to the sample container arrangement position, the main control unit 51 of the control unit 50 turns on the valve drive signal through the valve drive signal output unit 52 and outputs the second control signal through the control signal output unit 55. (Step S201, Step S202). Thus, the valve 25 is opened, and the three-way valve 14 is brought into a state where the syringe pipe 15 and the probe pipe 16 are in communication, that is, a state where the B end and the C end are opened. At this time, the control unit 50 (main control unit 51) outputs a syringe pump drive signal through the syringe pump drive processing unit 54 (step S203). As a result, the syringe pump 17 is driven, and a predetermined amount of air can be sucked into the pipe through the probe 19. As a result, a predetermined amount of air layer is formed at the tip of the probe 19.

  After sucking a predetermined amount of air in this way, the main control unit 51 turns off the valve drive signal through the valve drive signal output unit 52 (step S204) and closes the valve 25. At this time, the probe 19 is moved downward by the probe driving unit, and the tip of the probe 19 is immersed in the liquid sample in the sample container.

  The main control unit 51 of the control unit 50 detects the pressure value detected by the second pressure sensor 24 through the second pressure sensor detection processing unit 57, and the inside of the pipe (in the probe pipe 16 and the syringe pipe 15) is a memory. It is determined whether or not a predetermined pressure state stored in 61, that is, a negative pressure state (step S205). Here, in order to bring the inside of the pipe into a negative pressure state, the syringe pump 17 is caused to perform a suction operation corresponding to the amount obtained by adding the surplus to the total discharge amount. When determining that the inside of the pipe is in a negative pressure state, the main control unit 51 outputs a syringe pump stop signal through the syringe pump drive processing unit 54 (step S206), and stops driving the syringe pump 17. Let

  Thereafter, the main control unit 51 turns on the valve drive signal through the valve drive signal output unit 52 and starts measuring time through the time measurement unit 58 (steps S207 and S208). At this time, the main control unit 51 performs a detection process of the pressure value (pressure value in the pipe) detected by the second pressure sensor 24 through the second pressure sensor detection processing unit 57 (step S209). Then, the main control unit 51 determines whether or not a predetermined time has passed (step S210). When the predetermined time has passed, the main control unit 51 ends the time measurement through the time measurement unit 58. Then, the pressure value detection process through the second pressure sensor detection processing unit 57 is terminated (steps S211 and S212).

  After performing the time measurement and pressure detection processing in this way, the main control unit 51 calculates the correlation between the pressure in the pipe and the flow rate of the liquid sample through the pressure-flow rate calculation unit 59 as follows. (Step S213), and the current process is terminated. Here, for convenience of explanation, the calculation of the correlation when the air layer formed in step S203 described above is 1 μl and the suction operation by the syringe pump 17 is 2 μl will be described.

  When the air layer is 1 μl and the suction operation by the syringe pump 17 is 2 μl, the pressure change in the pipe measured in the above-described step S208 and step S209 is shown as a broken line in FIG. Since the temperature inside the pipe is considered to be kept constant by the fan 26, Boyle's law is established, the product of pressure and volume is constant, and the volume of the air layer is expressed by the following equation (2). Is required.

Formula (2) V (t) = V0 × (P0 / P (t))
Here, P0 represents an initial pressure, V0 represents an initial volume, P (t) represents a pressure at an arbitrary time t, and V (t) represents a volume at an arbitrary time t.

  The volume of the air layer calculated | required by the said Formula (2) is shown as the continuous line of FIG. Here, since the decrease in the volume of the air layer is equal to the amount of the sucked liquid sample, by calculating the rate of change (slope) of the volume of the air layer at a certain pressure, the pressure difference in the dispensing device and the liquid sample A relationship with the flow rate (hereinafter also referred to as a pressure difference-flow rate relationship) can be obtained, and this is shown in FIG. And the correlation between a pressure and a flow volume is computable by measuring the pressure in piping and using FIG.

  That is, the main control unit 51 obtains the volume change of the air layer from the pressure change measured in step S208 and step S209 through the pressure-flow rate calculation unit 59, and the volume at the pressure determined from the obtained volume change. By calculating the rate of change, the pressure difference-flow rate relationship is obtained. Then, the correlation between the pressure in the pipe and the flow rate of the liquid sample is calculated from the pressure in the pipe detected through the second pressure sensor detection processing unit 57 and the pressure difference-flow rate relationship. The calculated correlation is stored in the memory 61.

  The probe 19 is moved up by the probe driving unit and moved to the position where the reaction vessel is arranged. Thereafter, the probe 19 is moved downward again by the probe driving unit.

  After the probe 19 is moved downward again, the control unit 50 (main control unit 51) outputs the first control signal through the control signal output unit 55. As a result, the three-way valve 14 is brought into a state where the cleaning water introduction pipe 13 and the probe pipe 16 communicate with each other. By the way, the internal pressure of the washing water tank 11 is always detected by the first pressure sensor 22, and the air pump 20 is driven as necessary so that the detected pressure is constant. That is, the main control unit 51 of the control unit 50 detects and processes the pressure value detected by the first pressure sensor 22 through the first pressure sensor detection processing unit 56, and outputs an air pump drive signal through the air pump drive processing unit 53. Alternatively, the pressure in the washing water tank 11 is made constant by outputting an air pump stop signal.

  On the other hand, the main control unit 51 of the control unit 50 transmits the correlation calculated by the pressure-flow rate calculation unit 59 stored in the memory 61 through the valve opening time calculation unit 60 and the second pressure sensor detection processing unit 57. The flow rate of the liquid sample is calculated from the detected pressure in the pipe, and the opening time of the valve 25 is calculated from the calculated flow rate of the liquid sample and a predetermined desired discharge amount stored in the memory 61. To do.

  After calculating the opening time of the valve 25 through the valve opening time calculation unit 60, the main control unit 51 turns on the valve driving signal through the valve driving signal output unit 52 for the calculated opening time of the valve 25 to switch the valve 25. Establish.

  As described above, since the internal pressure of the cleaning water tank 11 is kept constant, the liquid sample is discharged from the probe 19 at a constant flow rate when the valve 25 is opened. Therefore, when the valve 25 is opened for a desired time, a desired amount of liquid sample can be accurately discharged.

  After completion of the discharge of the liquid sample into the reaction container, the probe drive unit moves the probe 19 to a position where another reaction container is arranged, and repeats the above-described discharge of the liquid sample to perform a dispensing operation.

  As described above, in the dispensing apparatus according to Embodiment 2 of the present invention, the main control unit 51 and the pressure-flow rate calculation unit 59 constitute the first calculation means, and the main control unit 51 and the valve opening time calculation unit 60. Constitutes the second calculation means, and the main control portion 51 and the valve drive signal output portion 52 constitute the valve opening operation control means. According to such a dispensing apparatus, when the inside of the pipe is in a negative pressure state, the valve 25 is opened for a predetermined time, and the liquid sample is caused to flow into the pipe to measure the pressure in the pipe. The correlation between the pressure in the pipe and the flow rate of the liquid sample is calculated, the flow rate of the liquid sample is calculated from the calculated correlation and the measured pressure in the pipe, and the flow rate of the liquid sample is predetermined. Since the opening time of the valve 25 is calculated from the desired discharge amount, and the valve 25 is opened for the calculated opening time of the valve 25, the liquid sample can be discharged accurately, the viscosity of the liquid sample, the diameter of the probe 19 and the like. There is no possibility that the dispensing amount will fluctuate due to the influence of the above. Therefore, the dispensing accuracy can be improved.

  The preferred embodiment 1 and embodiment 2 of the present invention have been described above, but the present invention is not limited to these, and various modifications can be made.

  For example, in the first embodiment described above, the valve 25 is opened when the valve drive signal is on, that is, the valve 25 is opened and closed by turning on and off the valve drive signal. A configuration may be adopted in which the valve is opened by outputting a valve opening signal at a predetermined time, and the valve is closed by outputting a valve closing signal at a predetermined time. In such a configuration, the valve opening signal is output earlier by the opening operation delay time calculated through the opening operation delay time calculation unit, and the valve closing operation calculated through the closing operation delay time calculation unit is output. If the valve closing signal is output as early as the delay time, the desired amount of liquid sample can be discharged accurately, and the dispensing volume varies due to individual valve differences, changes over time, ambient temperature, control circuit, etc. There is no fear of it. Therefore, the dispensing accuracy can be improved.

  Moreover, in Embodiment 2 mentioned above, dispensing unit 10 'was equipped with the air pump 20 and the 1st pressure sensor 22, However, in this invention, as shown in FIG. The dispensing unit 100 may not be provided. In such a configuration, it is only necessary to adjust the pressure in the pipe with the syringe pump 17 and the air pump and the first pressure sensor are not required. Therefore, the cost can be reduced.

  As described above, the dispensing apparatus according to the present invention is useful for, for example, sucking a liquid sample containing a specimen or a reagent and discharging the sucked liquid sample to perform dispensing.

It is the schematic diagram which showed typically the structure of the dispensing apparatus in Embodiment 1 of this invention. It is the block diagram which showed typically the structure of the control unit in FIG. It is the flowchart which showed the processing content of the main control part of the control unit in FIG. 6 is a time chart showing measurement of an operation delay time of the valve 25. It is the schematic diagram which showed typically the structure of the dispensing apparatus in Embodiment 2 of this invention. It is the block diagram which showed typically the structure of the control unit in FIG. It is the flowchart which showed the processing content of the main control part of the control unit in FIG. It is the graph which showed the pressure change in measurement time. It is the graph which showed the relationship between a pressure difference and flow volume. It is the schematic diagram which showed typically the structure of the modification of the dispensing apparatus in Embodiment 2 of this invention.

Explanation of symbols

10, 10 ', 100 Dispensing unit 11 Washing water tank 12 Stopper 13 Washing water introduction pipe 14 Three-way valve 15 Syringe pipe 16 Probe pipe 17 Syringe pump 18 Piston 19 Probe 20 Air pump 21 Air supply pipe 22 First pressure sensor 23 Detection Piping 24 Second pressure sensor 25 Valve 26 Fan 30, 50 Control unit 31, 51 Main control unit 32, 52 Valve drive signal output unit 33, 53 Air pump drive processing unit 34, 54 Syringe pump drive processing unit 35, 55 Control signal Output unit 36, 56 First pressure sensor detection processing unit 37, 57 Second pressure sensor detection processing unit 38, 58 Time measurement unit 39 Opening operation delay time calculation unit 40 Closing operation delay time calculation unit 41 Valve drive correction unit 42, 61 Memory 59 Pressure-flow rate calculation unit 60 When valve is open Calculation unit

Claims (3)

A tip that is connected to the probe, and a flow path through which fluid moves;
A valve that is provided at a tip region of the flow path and opens and closes based on an output drive signal to allow and restrict movement of fluid in the flow path;
In a dispensing apparatus that sucks a liquid sample from the probe by moving a fluid in the flow path and discharges the sucked liquid sample to perform dispensing.
A delay time calculating means for calculating an operation delay time of the valve by measuring a time from when the drive signal is output until the pressure in the flow path changes;
And a valve control means for controlling the operation time of the valve based on the operation delay time calculated by the delay time calculation means.   When the valve is closed and the flow path is at a positive pressure, the delay time calculating means outputs a drive signal for opening the valve until the pressure in the flow path decreases. The valve opening operation delay time is calculated by measuring the time, while a drive signal for closing the valve is output when the valve is opened and the flow passage is pressurized. The dispensing apparatus according to claim 1, wherein the valve closing operation delay time is calculated by measuring a time from when the pressure is increased until the pressure in the flow path increases. A flow path in which the tip is connected to the probe and the fluid moves inside;
A valve that is provided at a tip region of the flow path and permits and restricts movement of fluid in the flow path by opening and closing;
In a dispensing apparatus for sucking a liquid sample from the probe by moving a fluid in the flow path and discharging the sucked liquid sample to perform dispensing,
Fluid suction means for sucking the fluid in the flow path and bringing the flow path into a negative pressure state when air is introduced into the flow path to close the valve;
When the fluid suction means brings the inside of the flow path into a negative pressure state, the valve is opened for a predetermined time, the liquid sample is allowed to flow into the flow path, and the pressure in the flow path is measured. First calculating means for calculating a correlation between the pressure in the flow path and the flow rate of the liquid sample;
The flow rate of the liquid sample is calculated from the correlation calculated by the first calculation means and the measured pressure in the flow path, and the valve is calculated from the flow rate of the liquid sample and a predetermined desired discharge amount. Second calculating means for calculating the opening time of
A dispensing apparatus comprising: a valve opening operation control unit configured to control an opening operation of the valve according to a valve opening time calculated by the second calculation unit.

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