Suction and ejection device

Abstract

The air-displacement type suction and discharge device enables the proper suction or discharge of highly viscous fluids. [Solution] A suction discharge device comprising a pump 105, a tip mounting section 103 to which a tip 120 is detachably attached, flow paths 131 and 140 provided between the tip mounting section and the pump, and on / off valves 104 and 132 provided in the middle of the flow paths for switching between a state in which the flow paths are open to the atmosphere and a state in which they are not open to the atmosphere.

Description

Technical Field

[0001] The present invention relates to a fluid suction and discharge device.

Background Art

[0002] In a pretreatment device or the like that performs predetermined pretreatment on a sample before analysis, a suction and discharge device that sucks a sample or a reagent or the like from a container and discharges it into another container is used (for example, Patent Document 1). Usually, a dispensing nozzle that can move vertically, longitudinally, and laterally is provided in the suction and discharge device, and a disposable tip is attached to the tip of the dispensing nozzle. When performing dispensing by such a suction and discharge device, the dispensing nozzle is moved by a drive mechanism such as a motor to insert the tip (lower end) of the tip into a container containing a target reagent or the like, and a liquid in the container is sucked into the tip by a predetermined amount by the action of a pump connected to the other end of the dispensing nozzle. Thereafter, the dispensing nozzle is moved to place the tip of the tip on another container, and the liquid in the tip is discharged into the other container by a predetermined amount by the action of the pump.

[0003] By the way, conventionally, when dispensing a cream-like fluid (high-viscosity fluid), a spoon is generally used, but in order to achieve automation, there is a desire to perform dispensing of such a high-viscosity fluid by the above-described suction and discharge device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Suction and discharge devices include air displacement type devices, which use air between the pressurized part of the pump (for example, the piston in a piston pump) and the liquid in the tip, and direct displacement type devices, which do not use air. The aforementioned pretreatment devices are often equipped with the highly versatile air displacement type suction and discharge device.

[0006] However, when a highly viscous fluid like the one described above is drawn in by an air-displacement type suction discharge device, air is drawn in between the pressurized part of the pump and the highly viscous fluid inside the tip for a while even after the pump's suction operation is stopped. As a result, when the tip of the tip is lifted out of the fluid, air is drawn in from the tip, creating an air passage in the highly viscous fluid inside the tip, which can prevent the fluid from being discharged. Also, when discharging a highly viscous fluid with a similar suction discharge device, the discharge of the highly viscous fluid may not stop immediately even after the pump's discharge operation is stopped.

[0007] The present invention has been made in view of the above points, and its purpose is to enable the appropriate suction or discharge of such highly viscous fluids by an air displacement type suction and discharge device. [Means for solving the problem]

[0008] The suction and discharge device according to the present invention, which was developed to solve the above problems, Pump and A tip mounting section to which the tip can be detachably attached, A flow path is provided between the chip mounting portion and the pump, An atmospheric vent section is provided in the middle of the aforementioned flow path to switch between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, It possesses the following characteristics.

[0009] The fluid sampling method according to the present invention, which was developed to solve the above problems, A method for collecting fluid from a container using a suction and discharge device having a pump, a tip mounting section to which a tip can be detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A suction step is performed by operating the pump with the tip of the tip placed in the fluid inside the container, thereby drawing the fluid into the tip. After the suction step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, After the aforementioned air release step is performed, a tip lifting step is performed to lift the tip from the fluid, It possesses the following characteristics.

[0010] The fluid discharge method according to the present invention, which was developed to solve the above problems, A method for discharging fluid from a tip in a suction discharge device having a pump, a tip mounting section to which a tip is detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A discharge step of discharging the fluid in the tip by operating the pump, After the discharge step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, It possesses the following characteristics. [Effects of the Invention]

[0011] According to the suction and dispensing device and fluid suction method using the present invention having the above configuration, the tip of the tip is placed in the fluid to be dispensed, the fluid is suctioned into the tip, and then the pump is stopped and the flow path is opened to the atmosphere before the tip is withdrawn from the fluid. As a result, even if the fluid is a highly viscous fluid, the above-mentioned air passages are not formed in the fluid inside the tip, and the fluid can be properly suctioned.

[0012] Furthermore, according to the suction discharge device and fluid discharge method using the present invention having the above configuration, after discharging a predetermined amount of the fluid held in the tip, the pump is stopped and the flow path is opened to the atmosphere, thereby immediately stopping the discharge of the fluid from the tip, even if the fluid is a highly viscous fluid. [Brief explanation of the drawing]

[0013] [Figure 1] A schematic diagram of a suction and discharge device according to one embodiment of the present invention. [Figure 2] A flowchart illustrating the operation of the aforementioned suction and discharge device. [Modes for carrying out the invention]

[0014] The embodiments for carrying out the present invention will be described below with reference to the drawings. Figure 1 is a schematic diagram of the suction and discharge device according to this embodiment, and Figure 2 is a flowchart showing the operation of the suction and discharge device.

[0015] The suction and discharge device according to this embodiment includes a suction and discharge head 101, a suction and discharge head moving mechanism 102 for moving the suction and discharge head 101, a chip mounting portion 103 provided on the suction and discharge head 101, a pump 105, a first electronic balance 107 on which a suction source container 106 containing the fluid to be dispensed is placed (corresponding to the suction source weight measurement unit in the present invention), a second electronic balance 109 on which a discharge destination container 108 into which the fluid is discharged is placed (corresponding to the discharge destination weight measurement unit in the present invention), a control unit 110, a display unit 111 including a liquid crystal display, etc., and an input unit 112 including operation buttons or dials, etc.

[0016] The suction and discharge head moving mechanism 102 includes a motor or the like (not shown) and moves the suction and discharge head 101 up and down, back and forth, and left and right based on an instruction from the control unit 110. The chip mounting portion 103 is a substantially cylindrical protrusion protruding downward from the suction and discharge head 101. The lower end side of the chip mounting portion 103 has a structure that can be fitted to the upper end portion of a tubular chip 120 having a circular cross-section with a smaller diameter from the upper end to the lower end. Incidentally, the suction and discharge head 101 may be further provided with a chip removal mechanism (not shown) for removing the chip 120 from the chip mounting portion 103.

[0017] Inside the suction and discharge head 101, a first passage 131 extending vertically is formed. The lower end of the first passage 131 communicates with the internal space of the chip mounting portion 103, and the upper end of the first passage 131 is connected to a flexible tube 140 leading to the pump 105. Here, the first passage 131 and the tube 140 correspond to the flow path in the present invention.

[0018] As the pump 105, for example, a peristaltic pump, a diaphragm pump, a syringe pump, or the like can be used, but it is not limited thereto.

[0019] Inside the suction and discharge head 101, a second passage 132 extending laterally is further formed. One end of the second passage 132 is connected to the middle part of the first passage 131, and the other end is open. An on-off valve 104 for opening and closing the second passage 132 is provided on the second passage 132. Here, the second passage 132 and the on-off valve 104 correspond to the atmosphere release part in the present invention. Note that the positions of the second passage 132 and the on-off valve 104 are not limited to the above. As long as it is on the flow path from the chip mounting part 103 to the pump 105, they may be provided at any position. The on-off valve 104 switches between a state where the second passage 132 is open (hereinafter referred to as the atmosphere release state) and a state where the second passage 132 is closed (hereinafter referred to as the airtight state) based on an instruction from the control unit 110.

[0020] The control unit 110 is configured around a microcomputer including, for example, a CPU, a RAM, a ROM, etc. It makes a predetermined determination based on the output signals from the first electronic balance 107 and the second electronic balance 109, and generates a control signal for performing a dispensing operation (suction operation and discharge operation) described later, and sends it to the suction and discharge head movement mechanism 102, the pump 105, and the on-off valve 104.

[0021] Hereinafter, the operation when sucking a highly viscous fluid from the suction source container 106 into the chip 120 and discharging the highly viscous fluid in the chip 120 by a predetermined amount to each of the plurality of discharge destination containers 108 by the suction and discharge device according to the present embodiment will be described while referring to the flowchart of FIG. 2.

[0022] The amount of high-viscosity fluid to be drawn from the suction source container 106 into the tip 120 (hereinafter referred to as the set suction amount), the amount of high-viscosity fluid to be discharged from the tip 120 to each discharge destination container 108 (hereinafter referred to as the set discharge amount), and the number and location of the discharge destination containers 108 are set in advance by the user using the input unit 112 and stored in the control unit 110. At this time, (set suction amount) ≥ (set discharge amount) × (number of discharge destination containers). The user also inputs the density of the high-viscosity fluid to be dispensed, along with the values ​​of the set suction amount and set discharge amount (both volume values), and stores them in the control unit 110. Alternatively, the control unit 110 may store multiple fluids and the density of each fluid in advance, and the user may be allowed to select the fluid to be dispensed from among the multiple fluids stored in the control unit 110.

[0023] Furthermore, before starting the dispensing operation using the suction and dispensing device according to this embodiment, the suction source container 106 containing the high-viscosity fluid to be dispensed is placed on the first electronic balance 107, and the plurality of dispensing destination containers 108 are placed on the second electronic balance 109. In addition, the tip 120 is attached to the tip attachment section 103 in advance.

[0024] First, when the user performs a predetermined operation on the input unit 112 to instruct the start of dispensing, the suction discharge head moving mechanism 102 moves the suction discharge head 101 above the suction source container 106 under the control of the control unit 110, and then lowers the suction discharge head 101 to position the tip of the tip 120 inside the highly viscous fluid (Step 1). At this time, the on / off valve 104 is in the airtight state described above.

[0025] Next, under the control of the control unit 110, the suction operation by the pump 105 is started (step 2). As a result, the air in the flow path from the pump 105 through the tube 140, the first passage 131, and the internal space of the tip mounting section 103 to the tip 120 is sucked in by the pump 105, creating negative pressure in the flow path, and consequently the highly viscous fluid in the suction source container 106 is sucked into the tip 120.

[0026] The control unit 110 monitors the measurement value from the first electronic balance 107 at this time and repeatedly determines at predetermined time intervals whether or not the suction of the set amount of high-viscosity fluid has been completed (step 3). This determination is made, for example, by converting the difference (weight) between the measurement value of the first electronic balance 107 before the start of the suction operation and the current measurement value into volume using the density of the high-viscosity fluid stored in the control unit 110, and confirming whether or not the volume has reached the set suction amount.

[0027] Then, when it is determined that the suction of the set amount of high-viscosity fluid has been completed (i.e., when the answer is Yes in step 3), the control unit 110 stops the suction operation by the pump 105 and switches the on / off valve 104 to the above-mentioned open-to-the-air state (step 4). As a result, air flows into the first passage 131 via the second passage 132, and the negative pressure in the flow path is eliminated.

[0028] Subsequently, the suction discharge head moving mechanism 102 moves the suction discharge head 101 upward, thereby lifting the tip 120 from the highly viscous fluid (step 5).

[0029] Then, the on / off valve 104 is switched to the airtight state described above (step 6), and the suction discharge head 101 is moved so that the tip of the tip 120 is positioned above one of the plurality of discharge destination containers 108 (step 7). Steps 6 and 7 may be performed in the reverse order. Subsequently, under the control of the control unit 110, the discharge operation by the pump 105 is started (step 8). As a result, the flow path is pressurized to a positive pressure, and the high-viscosity fluid in the tip 120 is discharged into the discharge destination container 108.

[0030] The control unit 110 monitors the measurement value from the second electronic balance 109 at this time and repeatedly determines at predetermined time intervals whether the discharge of the set discharge amount of high-viscosity fluid has been completed (step 9). This determination is made, for example, by converting the difference (weight) between the measurement value of the second electronic balance 109 before the start of the discharge operation and the current measurement value into volume using the density of the high-viscosity fluid stored in the control unit 110, and confirming whether the volume has reached the set discharge amount.

[0031] Then, when it is determined that the discharge of the high-viscosity fluid at the set discharge amount is complete (i.e., when the answer is Yes in step 9), the control unit 110 stops the discharge operation by the pump 105 and switches the on-off valve 104 to the above-mentioned open-to-the-air state (step 10). As a result, the air in the first passage 131 is discharged into the atmosphere via the second passage 132, and the positive pressure in the flow path is eliminated.

[0032] Subsequently, the control unit 110 determines whether the discharge of the high-viscosity fluid to all pre-set discharge destination containers 108 has been completed (step 11). If it determines that it has not been completed, it returns to step 6, switches the on / off valve 104 to an airtight state, moves the suction discharge head 101 using the suction discharge head moving mechanism 102 to position the tip of the tip 120 above the next discharge destination container 108 (step 7), and discharges the high-viscosity fluid to the next discharge destination container 108 in the same manner as in steps 8 to 10 described above. After that, steps 6 to 11 are repeatedly executed until it is determined in step 11 that the discharge of the high-viscosity fluid to all discharge destination containers 108 has been completed (i.e., until step 11 is answered Yes), and the series of operations ends when step 11 is answered Yes.

[0033] As described above, according to the suction and discharge device of this embodiment, by switching the on-off valve 104 from an airtight state to an open-to-the-atmosphere state before lifting the tip 120 from the highly viscous fluid to eliminate the negative pressure inside the tip 120, it is possible to prevent air from being sucked in from the tip of the tip 120 when the tip 120 is lifted. As a result, it is possible to avoid a situation in which an air passage is formed in the highly viscous fluid inside the tip 120, making it impossible to discharge the fluid. Furthermore, by switching the on-off valve 104 from an airtight state to an open-to-the-atmosphere state and releasing the positive pressure inside the tip 120, it is possible to immediately stop the outflow of the highly viscous fluid from the tip 120.

[0034] Furthermore, according to the suction and discharge device of this embodiment, by stopping the suction operation of the pump 105 when it is determined that the amount of highly viscous fluid suctioned has reached a set suction amount based on the measurement value of the first electronic balance 107, an accurate amount of highly viscous fluid can be drawn into the tip 120. Moreover, according to the suction and discharge device of this embodiment, by stopping the discharge operation of the pump 105 when it is determined that the amount of highly viscous fluid discharged has reached a set discharge amount based on the measurement value of the second electronic balance 109, an accurate amount of highly viscous fluid can be discharged into each discharge destination container 108.

[0035] Although specific examples of embodiments for carrying out the present invention have been described above, the present invention is not limited to the above embodiments, and modifications are permitted as appropriate within the scope of the spirit of the present invention. For example, the suction and discharge device according to the present invention may not include the first electronic balance 107 and the second electronic balance 109 as described above, and the control unit 110 may determine whether the suction of a set amount of high-viscosity fluid has been completed and whether the discharge of a set amount of high-viscosity fluid has been completed based on the drive amount of the pump 105. Alternatively, without making such a determination, the suction or discharge operation by the pump 105 may be stopped when the pump 105 has been driven by a preset drive amount, and the on-off valve 104 may be switched from an airtight state to an open state.

[0036] Furthermore, in the above embodiment, the control of the pump 105 and the on-off valve 104, and the movement of the suction discharge head 101 are performed automatically, but these may be performed manually by the user. In that case, the suction discharge device according to this embodiment will be used by the user by gripping it, and the control of the pump 105 and the on-off valve 104 will be performed by the user by operating the operation buttons or the like provided on the input unit 112.

[0037] Furthermore, in the above embodiment, the highly viscous fluid drawn into the tip 120 is dispensed into multiple discharge containers 108, but the highly viscous fluid drawn into the tip 120 may be discharged into a single discharge container 108.

[0038] Furthermore, the atmospheric vent in the present invention is not limited to one equipped with an on / off valve 104 that opens and closes the second passage 132 as described above. For example, it may be equipped with a three-way valve that switches between a state in which the tip mounting portion 103 is connected to the first passage 131 (corresponding to the airtight state described above) and a state in which the tip mounting portion 103 is connected to the second passage 132 (corresponding to the atmospheric vent state described above). [Pattern] It will be obvious to those skilled in the art that the exemplary embodiments described above are specific examples of the following embodiments.

[0039] (Section 1) A suction discharge device according to one aspect of the present invention is: Pump and A tip mounting section to which the tip can be detachably attached, A flow path is provided between the chip mounting portion and the pump, An atmospheric vent section is provided in the middle of the aforementioned flow path and switches between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, It possesses the following characteristics.

[0040] (Paragraph 2) The suction and discharge device relating to Paragraph 2 is, in the suction and discharge device relating to Paragraph 1, Furthermore, A control unit controls the pump and the atmospheric release section so as to stop the fluid suction operation and release the flow path to the atmosphere when the suction of a predetermined amount of fluid into the chip is complete. It possesses the following characteristics.

[0041] (Paragraph 3) The suction and discharge device relating to Paragraph 3 is, in the suction and discharge device relating to Paragraph 2, Furthermore, A suction source weight measuring unit for measuring the weight of the fluid inside the container from which the fluid is drawn. It has, The control unit determines whether or not the suction of the predetermined amount of fluid has been completed based on the measurement value obtained by the suction source weight measuring unit.

[0042] (Paragraph 4) The suction and discharge device relating to Paragraph 4 is, in the suction and discharge device relating to Paragraph 1, Furthermore, A control unit controls the pump and the atmospheric release section so as to stop the fluid discharge operation and release the flow path to the atmosphere when the discharge of a predetermined amount of fluid from the tip is complete. It possesses the following characteristics.

[0043] (Paragraph 5) The suction and discharge device relating to Paragraph 5 is, in the suction and discharge device relating to Paragraph 4, Furthermore, A discharge point weight measuring unit for measuring the weight of the fluid in the container at the discharge point of the fluid. It has, The control unit determines whether or not the predetermined amount of fluid has been discharged based on the measurement value obtained by the discharge destination weight measuring unit.

[0044] (Paragraph 6) The method for collecting the fluid relating to Paragraph 6 is: A method for collecting fluid from a container using a suction and discharge device having a pump, a tip mounting section to which a tip can be detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A suction step is performed by operating the pump with the tip of the tip placed in the fluid inside the container, thereby drawing the fluid into the tip. After the suction step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, After the aforementioned air release step is performed, a tip lifting step is performed to lift the tip from the fluid, It possesses the following characteristics.

[0045] (Paragraph 7) The method for discharging the fluid relating to Paragraph 7 is: A method for discharging fluid from a tip in a suction discharge device having a pump, a tip mounting section to which a tip is detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A discharge step of discharging the fluid in the tip by operating the pump, After the discharge step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, It possesses the following characteristics. [Explanation of Symbols]

[0046] 101... Suction / discharge head 102... Suction / discharge head movement mechanism 103...Chip mounting section 104... Atmospheric vent section 105... Pump 106...Suction source container 107...1st electronic balance 108…Discharge container 109…Second electronic balance 110... Control Unit 111...Display section 112...Input section 120... Tips 131...1st aisle 132…Second aisle 140...tube

Claims

1. Pump and A tip mounting section to which the tip can be detachably attached, A flow path is provided between the chip mounting portion and the pump, An atmospheric vent section is provided in the middle of the aforementioned flow path and switches between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A suction and discharge device having the following features.

2. Furthermore, A control unit controls the pump and the atmospheric release section so as to stop the fluid suction operation and release the flow path to the atmosphere when the suction of a predetermined amount of fluid into the chip is complete. A suction and discharge device according to claim 1, having the following features.

3. Furthermore, A suction source weight measuring unit for measuring the weight of the fluid inside the container from which the fluid is drawn. It has, The control unit determines whether or not the suction of the predetermined amount of fluid has been completed based on the measurement value obtained by the suction source weight measuring unit. The suction and discharge device according to claim 2.

4. Furthermore, A control unit controls the pump and the atmospheric release section so as to stop the fluid discharge operation and release the flow path to the atmosphere when the discharge of a predetermined amount of fluid from the tip is complete. A suction and discharge device according to claim 1, having the following features.

5. Furthermore, A discharge point weight measuring unit for measuring the weight of the fluid in the container at the discharge point of the fluid. It has, The control unit determines whether or not the discharge of the predetermined amount of fluid has been completed based on the measurement value obtained by the discharge destination weight measuring unit. The suction and discharge device according to claim 4.

6. A method for collecting fluid from a container using a suction and discharge device having a pump, a tip mounting section to which a tip can be detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A suction step is performed by operating the pump with the tip of the tip placed in the fluid inside the container, thereby drawing the fluid into the tip. After the suction step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, After the aforementioned air release step is performed, a tip lifting step is performed to lift the tip from the fluid, A method for collecting a fluid having [a certain characteristic].

7. A method for discharging fluid from a tip in a suction discharge device having a pump, a tip mounting section to which a tip is detachably attached, a flow path provided between the tip mounting section and the pump, and an atmospheric release section provided in the middle of the flow path for switching between a state in which the flow path is open to the atmosphere and a state in which it is not open to the atmosphere, A discharge step of discharging the fluid in the tip by operating the pump, After the discharge step is performed, the pump is stopped and the flow path is opened to the atmosphere by the atmospheric release section in an atmospheric release step, A method for discharging a fluid having [a certain characteristic].

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