JP2009162536A - Liquid sample dispenser and driving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid sample dispenser for accurately dispensing a required amount of a liquid sample to reaction containers. <P>SOLUTION: In the liquid sample dispenser 1 for dispensing a prescribed quantity of a liquid sample 14 held by a dispensing nozzle 2 to a plurality of reaction containers 13, a dispensing actuator control part 9 is provided with a discharge condition storage part 11, and the discharge condition storage part 11 stores the amount of discharge to the stroke of a plunger 6 in a syringe 4 connected to a dispensing actuator 7. The dispensing actuator control part 9 provides action commands for a dispensing actuator driving part 8 on the basis of previously stored strokes of the plunger 6 in the syringe 4 connected to the dispensing actuator 7; the amount of intake of the liquid sample; and the amount of discharge to the amount of air intake. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to, for example, a liquid sample dispensing apparatus and a driving method for accurately dispensing a necessary amount of a liquid sample into a reaction container.

  The liquid discharge head of Conventional Example 1 is a liquid discharge head that discharges a small amount of many kinds of liquids having different liquid physical constants, and is provided with a plurality of minute displacement generating members that cause a minute unit to act on the liquid, and a minute displacement generating member. And a liquid channel member filled with a liquid and a discharge port having a cross-sectional area substantially equal to the cross-sectional shape of the flow channel member, and the liquid is sprayed from the discharge port by resonance driving of the plate-shaped piezoelectric element. A liquid discharge head that can discharge and discharge a large amount of liquid in a short time and at a high speed, can be applied to administration of an affected part such as a reagent, and can provide a highly clean liquid discharge head. Yes (see, for example, Patent Document 1).

  7 is a schematic diagram showing a liquid discharge head and a liquid suction / supply connection piping path in Conventional Example 1, FIG. 8 is a perspective view of a flow path member of the liquid discharge head, FIG. 9 is a perspective view of the liquid discharge head, and FIG. FIG. 3 is a cross-sectional view of a discharge port of a liquid discharge head and a liquid discharge head.

In FIG. 7, the liquid discharge head 120 is supported by a movable conveyance member (not shown), and is moved and arranged above the liquid sample container 121, the cleaning tank 122, and the reaction container 123. The liquid discharge head 120 is connected to a syringe piston pump 125 by a connection pipe 124 made of Teflon (registered trademark). In addition to the connection pipe 124, another connection pipe 127 leading to the liquid supply tank 126 is connected to the syringe piston pump 125, and is sequentially connected to the liquid supply tank 126 via an electromagnetic valve 128 and a pump 129.
The above-described syringe pump 125 operates when the liquid is sucked, and the piston 130 reciprocates in the direction of the arrow 131 by a linear reciprocating actuator such as a stepping motor and a gear rack opinion (not shown). In addition, the liquid discharge head 120 and the syringe piston pump 125 are shown to be slightly up and down in the drawing in order to prevent a water head value difference, but are actually installed at substantially the same level.
The liquid supply tank 126 contains water to be washed water 132 or deionized ion exchange water, and is connected by a pump 129 to each connection pipe 124, 127, solenoid valve 128, syringe piston pump 125, and liquid. Washing water 132 is filled and supplied into the discharge head 120.
Here, a rectangular micro tube 133 having a rectangular cross section with a flow channel width of 50 μm × 500 μm and a length of 5 mm made of glass is used as the flow channel member, and a plate-shaped piezoelectric element 134 is used as the micro displacement generating member.

Next, when two plate-shaped piezoelectric elements 134 are installed on the outer surface of the long side of the cross section of the rectangular microtube 133, a conductive material electrode 135 that becomes an electrode is formed by screen printing in an area larger than the installation area of the plate-shaped piezoelectric element 134. Has been. As shown in FIG. 11, the plate-shaped piezoelectric element 134 is polarized in the pressure direction (arrow 136), silver electrodes 137 and 138 are formed on both sides of the plate thickness, and one of the silver electrodes 137 is electrically connected to the entire surface. Thus, the conductive material electrode 135 is joined.
In this way, one end face of the rectangular micropipe 133 on which the plate-shaped piezoelectric element 134 is formed serves as a discharge port 139, and the other end face is connected to the Teflon pipe 124 via the joint 140.
A thin water-repellent layer made of a fluorine-based material is formed on the end face of the discharge port 139 of the glass rectangular microtube 133.
Further, the plate-shaped piezoelectric element 134 is made of a soft piezoelectric material having a large piezoelectric constant and a large amount of displacement (for example, C-6 material, C-82 material manufactured by Fuji Ceramics Co., Ltd.). The side bonded to the conductive material electrode 135 is used as a negative electrode (GND electrode) and the outer surface silver electrode 138 is used as a positive electrode. A voltage having a predetermined voltage value and a predetermined waveform is applied to each electrode by a lead wire 141 from a drive circuit (not shown).
As described above, the liquid ejection head according to the conventional example 1 can eject liquid from the ejection port by the resonance of the plate-shaped piezoelectric element 134, and can eject a large amount of liquid in a short time at high speed. Applicable to etc.

  The dispensing device of Conventional Example 2 includes one outer tube having a discharge port at the tip, a first inner tube that is included in the outer tube and has a discharge port positioned in the vicinity of the discharge port of the outer tube, Dispensing into any one of a second inner tube having a discharge port contained in one inner tube and located near the discharge port of the first inner tube, and an outer tube, a first inner tube, and a second inner tube The dispensing liquid supply means for supplying the liquid, the carrier fluid supply means for supplying the carrier fluid to the pipe to which the dispensing liquid is not supplied, and the dispensing liquid from the discharge port of the pipe to which the dispensing liquid is supplied Before dropping by its own weight, it is equipped with a carrier fluid supply means for discharging the carrier fluid from the discharge port of the pipe to which the dispenser liquid is not supplied, and the outer pipe or the dispenser liquid is supplied by the dispenser liquid supply means Thus, the dispensing liquid is guided to the discharge port of the pipe. Further, when the carrier fluid is supplied to a pipe to which no dispensing liquid is supplied, the carrier fluid is guided to the discharge port of the pipe. Here, before the dispensing liquid drops by its own weight from the discharge port of the pipe to which the dispensing liquid is supplied, the carrier fluid is controlled from the discharge port of the pipe to which the dispensing liquid is not supplied by the control of the carrier fluid means by the supply control means. Is discharged, the carrier fluid acts on the dispensing liquid before dropping, and overcomes the surface tension to drop the dispensing liquid as droplets. Therefore, a very small amount of droplets smaller than the volume when dropping by its own weight is dispensed (see, for example, Patent Document 2).

  In FIG. 11, the schematic block diagram of the dispensing apparatus of the prior art example 2 is shown. This dispensing apparatus includes a pipette-shaped dispenser 201. The dispenser 201 has a double tube structure including an outer tube 202 and an inner tube 203 included in the outer tube 202. Below the dispenser 201, a substrate 204 such as a biochip as a dispensing partner is arranged.

In FIG. 12, the lower end part of the dispenser 201 is shown in an expanded sectional view. FIG. 13 is a sectional view taken along line AA in FIG. The outer tube 202 has a discharge port 202a at the lower end, which is the tip. The inner tube 203 includes a discharge port 203 a located in the vicinity of the discharge port 202 a of the outer tube 202. A gap passage 205 is formed between the outer tube 202 and the inner tube 203. As shown in FIG. 13, the shape of the periphery of the discharge port 203a of the inner tube 203 has an end surface shape that is simply cut perpendicularly to the axis of the tube material. The shape of the periphery of the discharge port 203a has an end surface shape obtained by simply cutting the pipe material perpendicularly to its axis. A water-repellent coating 206 is formed on the peripheral surface of the discharge port 203a by performing a water-repellent treatment using a silicone coating agent or the like, as indicated by a broken line in FIG.
As shown in FIG. 11, a liquid pipe 207 is connected to the inner pipe 203 of the dispenser 201. The upstream end of the liquid pipe 207 is connected to a tank 208 that stores the dispensed liquid and is disposed in the dispensed liquid. A first electromagnetic valve 209 is provided in the middle of the liquid pipe 207. An air pipe 210 for supplying hydraulic pressure feeding air is connected to the upper portion of the tank 208. In the middle of the air pipe 210, a pressure feed pressure regulator 211 for adjusting the pressure of the fluid pressure feed air is provided. The tank 208 is constantly supplied with air whose pressure has been adjusted by the pressure feeding pressure regulator 211. In this state, when the first electromagnetic valve 209 is opened, the dispensed liquid stored in the tank 208 is supplied to the inner pipe 203. In this conventional example, the liquid pipe 207, the tank 208, the first electromagnetic valve 209, the air pipe 210, and the pressure feed pressure regulator 211 constitute a dispensing liquid supply means for supplying a dispensing liquid to the inner pipe 203. The
As shown in FIG. 11, another air pipe 212 is connected to the outer tube 202 of the dispenser 201. Air as a carrier fluid is supplied to the air pipe 212. In the middle of the air pipe 212, a second electromagnetic valve 213 and a pressure regulator 214 for adjusting the pressure for adjusting the air pressure are provided. In this state, when the second electromagnetic valve 213 is opened, the transfer air is supplied to the gap passage 205 between the outer tube 202 and the inner tube 203. In this embodiment, a carrier fluid for supplying air as a carrier fluid to the gap passage 205 between the outer tube 202 and the inner tube 203 by the air pipe 212, the second electromagnetic valve 213 and the pressure regulator 214. Supply means are configured.
As shown in FIG. 11, the first electromagnetic valve 209 and the second electromagnetic valve 213 are each connected to a controller 215. The controller 215 controls opening and closing of the first electromagnetic valve 209 and the second electromagnetic valve 213 in order to control the supply timing of the dispensing liquid and air to the dispenser 201. In this embodiment, the controller 215 performs the second operation to discharge the carrier air from the discharge port 202a of the outer tube 202 in a pulsed manner before the dispensing liquid drops from the discharge port 203a of the inner tube 203 by its own weight. The electromagnetic valve 213 is controlled and corresponds to the supply control means of the present invention.

FIG. 14 is a time chart showing the opening / closing timing of the first solenoid valve 209 and the second solenoid valve 213 controlled by the controller 215. In this embodiment, as shown in FIGS. 14 (a) and 14 (b), the second electromagnetic valve 213 is opened with a slight delay from the opening of the first electromagnetic valve 209, and a predetermined time elapses thereafter. Both solenoid valves 209 and 213 are closed simultaneously.
In this conventional example, the pressure of the conveying air is set to “0.5 MPaG”. The operation interval of the second electromagnetic valve 213 is set to “ON = 10 ms / OFF = 490 ms”, whereby an air pressure pulse of “10 ms” is generated every “0.5 seconds”. In this embodiment, the pumping pressure of the dispensing liquid is variable in the range of “0.01 MPaG to 0.1 MPaG”. The inner diameter of the inner tube 203 is set to “φ50 μm”, and the outer diameter of the outer tube 202 is set to “φ100 μm”.

FIG. 15 is a conceptual diagram showing the mechanical relationship when the droplet 222 falls from the lower end opening 221a of the narrow tube 221. If the mass of the droplet 222 is “m”, the force pulling the droplet 222 downward is gravity “mg”. On the other hand, the force for pulling up the droplet 222 is “2πrα”. Here, “α” is “surface tension”, and “r” is “outer radius” of the opening 221a. Therefore, in order for the droplet 222 to fall, the droplet 222 needs to grow and its mass increase until the relationship “mg> 2πrα” is established.
According to the above-described conventional dispensing apparatus, when the first electromagnetic valve 209 is opened and the dispensing liquid is supplied from the tank 208 to the inner pipe 203, the dispensing liquid is supplied to the discharge port 203a of the inner pipe 203. Is guided. Further, when the second electromagnetic valve 213 is opened and the conveyance air is supplied to the outer pipe 202, the conveyance air to the discharge port 202a of the outer pipe 202 is guided.
Here, before the dispensing liquid drops from the discharge port 203a of the inner tube 203 by its own weight, the air for conveyance is discharged from the discharge port 202a of the outer tube 202 by the control of the second electromagnetic valve 213 by the controller 215. At this time, as shown in FIG. 16, the dispensing liquid is blown off by overcoming the surface tension and the like by the conveying air acting on the outer periphery thereof. Accordingly, an extremely small amount of dispensing liquid that is smaller than the volume when dropping by its own weight is dispensed onto the substrate 204. For this reason, it becomes possible to perform an extremely small amount of dispensing at the “nl” level.
Thus, in the dispensing apparatus of Conventional Example 2, since the water-repellent coating 206 is formed on the peripheral surface of the discharge port 203a of the inner tube 203 to which the dispensing solution is supplied, the dispensing solution is supplied from the discharge port 203a. Cutting is promoted and the volume of the dispensed solution is further reduced. In this sense, it is possible to promote an ultra-small amount of droplets to be dispensed, and to increase the precision of dispensing.

  The liquid discharging method and apparatus of the conventional example 3 that is controlled at high speed and with high precision performs discharge so that the liquid discharge flow rate from the discharge port is constant when performing quantitative discharge from the liquid storage container via the discharge valve. The pressure is applied to the liquid in advance before starting and / or the pressure in the vicinity of the discharge port after the end of discharge becomes a predetermined specific value (see, for example, Patent Document 3).

FIG. 17 is a cross-sectional view of an essential part showing an embodiment of a liquid dispensing apparatus, FIG. 18 is a flowchart showing a processing procedure of an automatic pressure regulator, and FIG. 19 is a cross-sectional view of an essential part showing another embodiment of the liquid dispensing apparatus. FIG.
The conventional example shown in FIG. 17 is an apparatus to which the liquid temperature control means shown in FIG. 20 is added. In FIG. 17, 301 denotes a liquid reservoir, and 302 denotes a needle valve as a discharge valve. FIG. 20 is an explanatory view of a liquid fixed quantity discharge device provided with a liquid temperature control means, a temperature sensor for measuring the temperature of the liquid in the storage container and the discharge valve, and a heating / cooling unit by inputting a signal from the temperature sensor. 17 is a device in which a temperature control unit that outputs a signal to the device and a heating / cooling unit that achieves a desired temperature by a signal from the temperature control unit, for example, are added to the device of FIG. 17. This is an example of covering
The temperature of the liquid is always controlled to be a desired temperature, and the liquid temperature in the storage container and the liquid temperature in the discharge valve are managed by the temperature control unit. If the distance between the liquid supply tube that connects the storage container and the discharge valve becomes long, or if the liquid passes through the liquid supply tube for a long time that the discharge interval is long and the temperature of the liquid can change, It is desirable to dispose a temperature sensor in the feeding tube and to cover a part or the entire length of the liquid feeding tube with a heating / cooling unit. In this case, it is desirable to determine the number of temperature sensors arranged in the liquid feeding tube according to the length of the liquid feeding tube and the discharge interval. Further, the same effect can be obtained even if all of the present apparatus is housed in a high-temperature tank capable of controlling the environmental temperature to a desired temperature.

As shown in FIG. 17, the liquid storage container includes, for example, a syringe 303 made of a synthetic resin material and a holder 304 that circumscribes and holds the syringe 303, and the holder 304 makes it possible to attach and detach the syringe. .
In addition, the pressure in the liquid storage container 301 is measured, and the measurement result is output as a control signal. The pressurizing means 305 that pressurizes the liquid in the liquid storage container 301 to a required pressure is screwed into a ball screw 307 attached to the output shaft of the motor 306 and is moved up and down as the ball screw 307 rotates. A plunger 310 is connected to the female screw member 308 via a rod 309, where the plunger 310 is preferably in fluid-tight contact with the syringe 303.
Further, here, the needle valve 302 connected to the liquid storage container 301 via the liquid channel 312 moves forward and backward in the outlet space 314 that communicates with the channel 312 and reaches the discharge port 313, and the discharge port 313. And a double-acting cylinder 316 that causes the needle 315 to advance and retreat. The needle 315 is connected to the piston 317 of the cylinder 316.
Further, here, a pressure sensor 318b for detecting the pressure of the liquid in the flow path 312 is disposed in the vicinity of the discharge port 313, as shown in the figure, at the connection portion of the flow path 312 to the needle valve 302. In addition, a control means 319 for inputting a detection signal from the pressure sensor 318b is provided. This control means 319 includes an input / output unit, a calculation unit, and a storage unit. Based on the detection results of the pressure sensors 318a and 318b, the control unit 319 automatically adjusts the discharge pressure at the start of discharge, and particularly in the flow path 312. In addition to controlling the operation of the motor 306 so that the liquid pressure in the vicinity of the outlet becomes a predetermined specific value at the time of stopping the discharge, more preferably also at the time of discharging, the rotation of the motor 306 in discharging the liquid It functions to control the operation of the switching valve 320 of the needle valve 302 as well as the speed and rotation time.

  When the liquid is discharged by the apparatus configured as described above, for example, the motor 306 is operated by the control means 319 based on the pressure detected by the pressure sensors 318a and 318b, and the plunger 310 in the syringe 303 is moved. The discharge pressure is automatically adjusted at the start of discharge, and further, the liquid pressure in the liquid flow path 312 is set to a predetermined specific value so that the flow path condition at the start of discharge is always constant. It shall be. Thereafter, a discharge start signal and a discharge pressure signal are output from the control means 319, and the motor 306 is rotated at a constant speed to pressurize the liquid in the syringe 303 to a required pressure. At the same time, the piston 317 of the cylinder 316 and thus the needle 315 is moved backward, the discharge port 313 is opened, and the discharge of the liquid from the discharge port 313 is started. By the way, when this discharge takes a relatively long time, the pressure detection by the pressure sensor 318b is also performed during the discharge, and the result is fed back to the operation of the motor 306 to correct the rotational speed, etc. It is preferable for improving the accuracy of quantitative discharge. When a predetermined time corresponding to the discharge of a predetermined amount of liquid has elapsed, a discharge end signal is output from the control means 319 to each of the motor 306 and the switching valve 320 to stop the rotation of the motor 306 and the needle valve 302. The closing operation is performed at the same time, thereby completing one fixed discharge. In this case, in particular, the needle 315 of the needle valve 302 always advances smoothly and quickly regardless of the liquid pressure, and mechanically closes the discharge port 313, thus providing excellent liquid drainage. Thus, the discharge port 313 can be completely closed, and unexpected liquid breakage can be sufficiently prevented.

As described above, the method and apparatus for discharging liquid that is controlled at high speed and precisely in Conventional Example 3 is a method for discharging or applying a small amount of liquid to a desired application shape at high speed and accurately without depending on the viscosity of the liquid. And a device can be provided. In particular, even when using highly viscous liquids or when applying at high speed, the line shape of the start and end points of the line can be controlled very easily. Thus, there can be provided a method and an apparatus capable of forming a uniform line shape without thinning or thickening the line. It is possible to provide a liquid discharge method and apparatus that can improve the liquid drainage property when discharging is stopped and can sufficiently prevent the liquid from leaking without fear of the filler being destroyed. It is possible to provide a method and an apparatus for discharging or applying a liquid that can make the drawing of a coating line uniform without requiring time for the liquid to obtain a constant flow rate.
JP 2001-232245 A (8th page, FIGS. 1 to 4) Japanese Patent No. 3734251 (page 10, FIGS. 1-6) JP 2001-46936 A (page 13, FIGS. 1-4)

However, in the conventional example, since the liquid sample cannot be sucked through the nozzle, it cannot be applied to an application for sucking and discharging the liquid sample. Further, the influence of the initial meniscus formed at the nozzle tip is not taken into consideration, and the dispensing actuator drive unit is controlled based on the relationship between the plunger stroke, the liquid sample suction amount, and the air suction amount when the liquid sample is discharged. Since the operation command is not commanded, there is a problem that the discharge accuracy (CV value, accuracy) is not improved.
The present invention has been made in view of such problems, and is based on the relationship between the plunger stroke, the liquid sample suction amount, the air suction amount, and the discharge amount when the liquid sample is discharged. Discharge all the inhaled liquid sample by instructing the operation command to accurately discharge the liquid sample regardless of the difference in surface tension due to the viscosity of the liquid sample at the nozzle tip and the difference in the initial meniscus after the liquid sample is aspirated. An object is to provide a liquid sample dispensing apparatus.

In order to solve the above problem, the present invention is configured as follows.
The invention according to claim 1 is a dispensing nozzle for sucking and holding a liquid sample, a syringe composed of a cylinder and a plunger for generating suction / discharge pressure of the liquid sample, a flexible tube for flowing the liquid sample, and the liquid A dispensing actuator for performing sample suction / discharge from the dispensing nozzle via the syringe and the flexible tube, a dispensing actuator driving unit for driving the dispensing actuator, and the dispensing actuator In the liquid sample dispensing apparatus, comprising a dispensing actuator control unit for controlling the drive unit, and dispensing the liquid sample held by the dispensing nozzle into a plurality of reaction containers in a predetermined amount, the dispensing actuator The control unit includes a discharge condition storage unit.

The invention according to claim 2 is a dispensing nozzle for sucking and holding a liquid sample, a syringe composed of a cylinder and a plunger for generating suction / discharge pressure of the liquid sample, a flexible tube for flowing the liquid sample, and the liquid A dispensing actuator for performing sample suction / discharge from the dispensing nozzle via the syringe and the flexible tube, a dispensing actuator driving unit for driving the dispensing actuator, and the dispensing actuator In the method of driving a liquid sample dispensing apparatus, comprising a dispensing actuator control unit for controlling the driving unit, and dispensing a predetermined amount of the liquid sample held by the dispensing nozzle into a plurality of reaction containers. The priming actuator control unit calculates the plunger drive parameter and the discharge amount stored in the discharge condition storage unit. It is intended to command an operation command to the dispensing actuator driving unit based on the engagement.
According to a third aspect of the present invention, the discharge parameter stored in the discharge condition storage unit is related to the plunger stroke, the liquid sample suction amount, and the discharge amount.
According to a fourth aspect of the present invention, the discharge parameter stored in the discharge condition storage section is related to the stroke of the plunger, the air intake amount, and the discharge amount.
According to a fifth aspect of the present invention, the discharge parameter stored in the discharge condition storage unit is a relationship between the stroke of the plunger, the liquid sample intake amount, the air intake amount, and the discharge amount.

According to the first and second aspects of the present invention, the dispensing actuator control unit includes a discharge condition storage unit, stores a drive parameter and a discharge amount of the plunger, and is dispensed from the dispensing actuator control unit. By giving a drive command to the liquid sample, the liquid sample can be accurately discharged regardless of the difference in surface tension due to the viscosity of the liquid sample at the nozzle tip or the difference in initial meniscus after the liquid sample is sucked.
According to a third aspect of the present invention, the discharge condition storage unit stores a discharge amount with respect to the liquid sample inhalation amount, and the dispensing actuator control unit performs an operation command based on a discharge operation pattern of the dispensing actuator. The pre-stored stroke of the plunger and the discharge amount with respect to the liquid sample suction amount can be used as an operation command to the dispensing actuator drive unit, so that the difference in surface tension due to the viscosity of the liquid sample at the nozzle tip and the liquid A liquid sample can be discharged with high accuracy regardless of the difference in initial meniscus after sample suction.
According to a fourth aspect of the present invention, a discharge amount with respect to an air intake amount is stored in the discharge condition storage unit, and the dispensing actuator control unit generates an operation command based on a discharge operation pattern of the dispensing actuator. Since the plunger stroke and the air suction amount stored in advance can be used as an operation command to the dispensing actuator drive unit, the difference in surface tension due to the viscosity of the liquid sample at the tip of the nozzle or the initial stage after suction of the liquid sample A liquid sample can be discharged with high accuracy regardless of the meniscus.
According to the fifth aspect of the present invention, the discharge condition storage unit stores the discharge amount with respect to the liquid sample inhalation amount and the air inhalation amount, and the dispensing actuator control unit is based on the discharge operation pattern of the dispensing actuator. The plunger stroke, the liquid sample suction amount, and the air suction amount stored in advance in the operation command can be used as the operation command to the dispensing actuator drive unit. The liquid sample can be discharged with high accuracy regardless of the difference in tension and the difference in initial meniscus after the liquid sample is sucked.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram illustrating a configuration of a liquid sample dispensing apparatus according to Embodiment 1 of the present invention.
In the figure, 1 is a liquid sample dispensing device, 2 is a dispensing nozzle for sucking and holding a liquid sample, 3 is a flexible tube made of a material such as urethane or fluororesin that flows the liquid sample, and 4 is composed of a cylinder and a plunger. Syringe, 5 is a cylinder, 6 is a plunger that discharges and sucks a liquid sample in the syringe, 7 is a dispensing actuator (for example, a linear motor), 8 is a dispensing actuator drive unit that drives the dispensing actuator , 9 is a dispensing actuator control unit for controlling the dispensing actuator drive unit, 10 is a CPU in the dispensing actuator control unit, and 11 is a stroke of the plunger 6 in the syringe 4 in the dispensing actuator control unit. A discharge condition storage unit for storing a discharge amount with respect to the liquid sample and the number of discharges after the liquid sample is sucked, 12 supplies a liquid sample Liquid sample container, 13 the reaction vessel for discharging the liquid sample, 14 is a liquid sample.
The dispensing nozzle 2 is hollow, and is shaped so that the inner diameter becomes smaller toward the tip. The dispensing nozzle 2 is held in a posture perpendicular to the liquid sample 14, sucks the liquid sample 14 contained in the liquid sample container 12, and discharges the liquid sample 14 to the reaction container 13. Although not shown, the dispensing nozzle 2 sucks and discharges the cleaning water in the cleaning water container. Various general methods can be employed as a cleaning water supply method and a suction / discharge method.
The cylinder 5 changes its volume in the syringe 4 as the plunger 6 moves. The cylinder 4 is connected to the dispensing nozzle 2 via the flexible tube 3. The plunger 6 moves upward on the surface of the syringe 4 so that the liquid sample 14 is sucked and the volume in the syringe 4 is increased, and the plunger 6 is discharged from the syringe 4 so that the volume in the syringe 4 is decreased by discharging the liquid sample 14. Move down the page. The plunger 6 is driven by a dispensing actuator 7 and is controlled by a dispensing actuator drive unit 8.
The dispensing actuator drive unit 8 is connected to the dispensing actuator control unit 9 and drives the dispensing actuator 7 based on the operation command. The dispensing actuator control unit 9 includes a CPU 10 and a discharge condition storage unit 11, and commands an operation command to the dispensing actuator drive unit 8 to discharge a predetermined liquid sample 14. The CPU 10 is input by the operator in advance, or based on the number of samples read from the identification mark displayed on the liquid sample container 12 and the desired analysis item and the required dispensing amount and dispensing order. The dispensing actuator drive unit 8 is commanded to correspond to the above.
Further, the discharge condition storage unit 11 stores the relationship among the stroke, pressure, nozzle diameter, discharge speed, liquid sample intake amount, air intake amount, and discharge amount during discharge.

Next, the operation of the first embodiment will be described with reference to FIGS.
FIG. 2 is a diagram illustrating a flow of the actuator control unit, and FIG. 3 is a diagram illustrating a suction state of the nozzle.
According to the procedure shown below, the liquid sample inhalation amount with respect to the discharge amount with good discharge accuracy is confirmed in advance by experiments. When the internal pressure is in a normal state where it does not decrease due to bubbles or the like, the fluid mass conservation law (inflow mass flow rate (density x flow velocity x cross-sectional area) and outflow flow rate (density x flow velocity x cross-sectional area) are equal) If it is established and the flow velocity at the tip of the nozzle is equal to or higher than the liquid running speed, the liquid can be discharged without causing a liquid pool.
Therefore, if the internal pressure is kept in a normal state, for example, the maximum speed, acceleration, and deceleration, which are plunger operation patterns (trapezoid pattern), are fixed, and the air intake amount is a constant value, the plunger stroke in the syringe, liquid The relationship between the sample inhalation amount and the discharge amount is confirmed and summarized as shown in the table of FIG.
(1) First, the liquid sample inhalation amount is stored (F0).
The liquid sample suction amount with respect to the discharge amount measured in advance is stored in the discharge amount storage unit.
(2) Aspirate the washing water (F1).
When the plunger 6 in the syringe 4 is suction driven by the actuator 7, the cleaning water 15 in a cleaning water container (not shown) is sucked from the nozzle 2. Alternatively, the cleaning water may be supplied to the flexible tube and the nozzle 2 from a pump (not shown) via a valve (not shown) and another flexible tube (not shown).
(3) Air is sucked (F2).
The plunger 6 in the syringe 4 is sucked and driven by the actuator 7, and a certain amount of air is sucked into the syringe 4 from the nozzle 2.
(4) A liquid sample is aspirated (F3).
The plunger 6 in the syringe 4 is sucked and driven by the actuator 7, and the liquid sample 14 in the liquid sample container 12 is sucked from the nozzle 2 based on the previously stored plunger operation pattern and the liquid sample suction amount.
(5) The liquid sample is discharged (F4).
The actuator 7 is driven to discharge from the plunger 6 in the syringe 4 by the thrust command to the actuator 7 based on the discharge operation pattern, and the liquid sample 14 is discharged from the nozzle 2 to the reaction container 13. Specifically, the plunger is driven by the actuator so that the cross-sectional area of the syringe × the stroke of the plunger = a part of the liquid sample suction amount + the air suction amount, and all the sucked liquid samples are discharged.
(6) Repeat (2) to (5) for each discharge.

As described above, in this embodiment, the liquid sample inhalation amount with respect to the discharge amount is stored in advance, and the inhaled liquid sample is ejected. Therefore, both the CV value and the accuracy can be ejected with high accuracy.
In addition, it is assumed that the operator prepares the liquid sample container 12 and the reaction container 13 below the nozzle 2, but the control unit 9 synchronizes with the actuator 7 and the nozzle 2 or the liquid sample container 12 and reaction container (not shown). The liquid sample may be automatically sucked / discharged by controlling a table or the like on which 13 is mounted.
The difference between the present invention and Patent Document 1, Patent Document 2, and Patent Document 3 is to the dispensing actuator driving unit in consideration of the relationship between the liquid sample suction amount, the air suction amount, and the discharge amount at the time of discharge. A liquid sample dispensing device that accurately discharges a liquid sample regardless of the difference in surface tension due to the viscosity of the liquid sample at the tip of the nozzle or the difference in the initial meniscus by discharging all the sucked liquid sample as an operation command That is.

Since the configuration of the second embodiment is the same as that of the first embodiment, the description thereof is omitted.
In accordance with the procedure shown below, the air intake amount with respect to the discharge amount with good discharge accuracy is confirmed in advance by experiments. When the internal pressure is kept in a normal state, for example, when the maximum speed, acceleration, and deceleration, which are the operation patterns of the plunger (trapezoid pattern), are fixed, and the reagent inhalation amount is constant, the plunger stroke and air inhalation amount in the syringe The relationship between the discharge amounts is confirmed and summarized as shown in the table of FIG.
Next, the operation of this embodiment will be described.
(1) First, the air intake amount is stored (F0).
The air intake amount with respect to the discharge amount measured in advance is stored in the discharge amount storage unit.
(2) The suction (F1) of the washing water is the same as in Example 1.
(3) Air is sucked (F2).
The actuator 6 sucks and drives the plunger 6 in the syringe 4, and sucks air from the nozzle 2 into the syringe 4 based on the air intake amount stored in advance.
(4) Liquid sample suction (F3) and (5) Liquid sample discharge (F4) are the same as in the first embodiment.
(6) Repeat (2) to (5) for each discharge.
As described above, in the second embodiment, the air suction amount with respect to the discharge amount is stored in advance, and the sucked liquid sample is discharged. Therefore, both the CV value and accuracy can be discharged with high accuracy.

Since the configuration of the third embodiment is the same as that of the first embodiment, the description thereof is omitted.
According to the procedure shown below, the liquid sample inhalation amount and the air inhalation amount with respect to the ejection amount, which have good ejection accuracy, are confirmed in advance by experiments. When the internal pressure is kept in a normal state and the maximum speed, acceleration, and deceleration, which are the operation patterns of the plunger (trapezoid pattern), are fixed, the plunger stroke, liquid sample inhalation volume, air inhalation volume, and discharge volume in the syringe The relationship is confirmed and summarized as shown in the table of FIG.
(1) First, the liquid sample intake amount and the air intake amount are stored (F0).
The liquid sample inhalation amount and the air inhalation amount with respect to the discharge amount measured in advance are stored in the discharge amount storage unit.
(2) The suction (F1) of the washing water is the same as in Example 1.
(3) Air is sucked (F2).
The actuator 6 sucks and drives the plunger 6 in the syringe 4, and sucks air from the nozzle 2 into the syringe 4 based on the air intake amount stored in advance.
(4) Liquid sample suction (F3), (5) Liquid sample discharge (F4) is the same as in the first embodiment.
(6) Repeat (2) to (5) for each discharge.
As described above, in the third embodiment, the liquid sample inhalation amount and the air inhalation amount with respect to the ejection amount are stored in advance, and all of the inhaled liquid sample is ejected.

As described above, according to the liquid sample dispensing device of the present invention, based on the relationship among the plunger stroke, the liquid sample suction amount, the air suction amount, and the discharge amount when the liquid sample is discharged, the actuator driving unit for dispensing is used. Discharge all the inhaled liquid sample by instructing the operation command to accurately discharge the liquid sample regardless of the difference in surface tension due to the viscosity of the liquid sample at the nozzle tip and the difference in the initial meniscus after the liquid sample is aspirated. be able to.
In this way, the liquid sample can be discharged accurately regardless of the difference in surface tension due to the viscosity of the liquid sample at the nozzle tip or the difference in the initial meniscus after the liquid sample is sucked. Applicable to devices and the like.

It is a figure which shows the structure of the liquid sample dispensing apparatus of 1st Example of this invention. It is a flowchart which shows operation | movement of the control part in 1st Example of this invention. It is sectional drawing which shows the suction state of the nozzle of FIG. It is a table | surface which shows the relationship of the stroke of the plunger in the syringe of 1st Example of this invention, the liquid sample suction | inhalation amount, and discharge amount. It is a table | surface which shows the relationship of the stroke of the plunger in the syringe of the 2nd Example of this invention, the air intake amount, and the discharge amount. It is a table | surface which shows the relationship of the stroke of the plunger in the syringe of the 3rd Example of this invention, the liquid sample inhalation amount, the air inhalation amount, and the discharge amount. FIG. 10 is a schematic diagram illustrating a liquid discharge head and a liquid suction / supply connection piping path in Conventional Example 1. 6 is a perspective view of a flow path member of a liquid discharge head of Conventional Example 1. FIG. FIG. 10 is a perspective view of a liquid discharge head according to a conventional example 1. It is a figure which shows the discharge outlet of the liquid discharge head of the prior art example 1. FIG. It is a schematic block diagram which shows the dispensing apparatus of the prior art example 2. It is an expanded sectional view which shows the lower end part of the dispenser of the prior art example 2. It is AA sectional view taken on the line of FIG. It is a time chart which shows the opening / closing timing of the 1st and 2nd solenoid valve of the prior art example 2. FIG. It is a conceptual diagram which shows the dynamic relationship at the time of a droplet falling from the thin tube of the prior art example 2. FIG. It is explanatory drawing which shows the effect | action that a dispensing liquid blows off from the dispenser of the prior art example 2. FIG. It is principal part sectional drawing which shows the aspect of the preferable liquid fixed quantity discharge apparatus used as the object to which the discharge pressure control means of the prior art example 3 is added. It is a flowchart figure which shows the process sequence of the automatic pressure regulating apparatus of the prior art example 3. It is principal part sectional drawing which shows another aspect of the preferable liquid fixed quantity discharge apparatus used as the object to which the discharge pressure control means of the prior art example 3 is added. It is drawing explaining the aspect of the liquid fixed quantity discharge apparatus provided with the liquid temperature control means of the prior art example 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid sample dispensing apparatus 2 Dispensing nozzle 3 Flexible tube 4 Syringe 5 Cylinder 6 Plunger 7 Dispensing actuator 8 Dispensing actuator drive unit 9 Dispensing actuator control unit 10 CPU
DESCRIPTION OF SYMBOLS 11 Discharge condition memory | storage part 12 Liquid sample container 13 Reaction container 14 Liquid sample 15 Washing water 16 Air

Claims (5)

Dispensing nozzle for sucking and holding a liquid sample, a syringe composed of a cylinder and a plunger for generating a suction and discharge pressure of the liquid sample, and a flexible tube for flowing the liquid sample by connecting the dispensing nozzle and the syringe A dispensing actuator for performing suction and discharge of the liquid sample from the dispensing nozzle via the syringe and the flexible tube, a dispensing actuator driving unit for driving the dispensing actuator, In a liquid sample dispensing apparatus that includes a dispensing actuator control unit that controls a dispensing actuator driving unit, and dispenses the liquid sample held by the dispensing nozzle into a plurality of reaction containers, a predetermined amount,
The dispensing actuator control unit includes a discharge condition storage unit, and the discharge condition storage unit stores a discharge amount with respect to a stroke of a plunger in a syringe connected to the dispensing actuator. Liquid sample dispensing device. A dispensing nozzle for sucking and holding a liquid sample, a syringe composed of a cylinder and a plunger for generating a suction and discharge pressure for the liquid sample, a flexible tube for flowing the liquid sample, and the syringe for sucking and discharging the liquid sample And a dispensing actuator to be implemented from the dispensing nozzle through the flexible tube, a dispensing actuator driving unit for driving the dispensing actuator, and a dispensing actuator for controlling the dispensing actuator driving unit In a driving method of a liquid sample dispensing apparatus that includes an actuator control unit and dispenses the liquid sample held by the dispensing nozzle into a plurality of reaction containers by a predetermined amount,
The dispensing actuator control unit commands an operation command to the dispensing actuator drive unit based on a relationship between the plunger drive parameter stored in the discharge condition storage unit and the discharge amount. A method for driving a liquid sample dispensing apparatus.   3. The method for driving a liquid sample dispensing apparatus according to claim 2, wherein the discharge parameter stored in the discharge condition storage unit is a relationship among the stroke of the plunger, the liquid sample suction amount, and the discharge amount.   3. The method of driving a liquid sample dispensing apparatus according to claim 2, wherein the discharge parameter stored in the discharge condition storage unit is a relationship among the stroke of the plunger, the air suction amount, and the discharge amount.   3. The liquid sample dispensing according to claim 2, wherein the discharge parameter stored in the discharge condition storage unit is a relationship among a stroke of the plunger, the liquid sample suction amount, the air suction amount, and the discharge amount. Device driving method.

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