JP2010065584A - Liquid sending pump and liquid sending method by this pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid sending pump capable of introducing liquid without leaving little bubble in a pump room. <P>SOLUTION: This liquid sending pump has a pump head having in a lower end part a seal member having a plunger through-hole, the pump room extended in the opposite direction of the seal member inside the pump head with the seal member as one end, a liquid inflow port arranged on the seal member upper surface side on a pump room side surface, a first liquid outflow port arranged on the seal member upper surface side on the pump room side surface on the opposite side of the liquid inflow port, a second liquid outflow port arranged in a pump room upper end part in the opposite direction of the seal member, a plunger inserted into the pump room via the plunger through-hole and advancing-retreating in the vertical direction in the pump room, and a plunger driving mechanism for advancing-retreating the plunger. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid feed pump used for feeding a small amount of liquid to a microfluidic chip. More specifically, the present invention relates to a plunger-type liquid feed pump used for feeding a small amount of liquid to a microchannel or the like of a microfluidic chip.

  Recently, microchannels and ports that form channels of a predetermined shape in a substrate, as is known by names such as Micro Total Analysis Systems (μTAS) or Lab-on-Chip (Lab-on-Chip) It has been proposed to perform various operations such as chemical reaction, synthesis, purification, extraction, generation and / or analysis of substances within the microstructure. A structure manufactured for such a purpose and having a microstructure such as a microchannel and a port in a substrate is generally called a microchannel chip, a microfluidic chip, a microchemical chip, or the like.

  Microchannel chips can be used in a wide range of applications such as genetic analysis, clinical diagnosis, drug screening, and environmental monitoring. Compared to the same type of equipment of the common size, the microchannel chip is (1) significantly less sample and reagent usage, (2) shorter analysis time, (3) higher sensitivity, (4) portable to the field. , It can be analyzed on the spot, and (5) can be disposable.

  Various structures of the microchannel chip 100 have been proposed, and there are complex structures such as a multilayer structure and a composite structure. In the entire structure or at least a part of the structure, there are two pieces as shown in FIG. The substrates 102 and 108 are bonded together. The necessity to perform the bonding is to seal the fine microchannel (flow channel) 104 to be formed, the liquid storage chamber and / or the reaction chamber. Each bonded surface side of the first substrate 102 and / or the second substrate 108 has a fine structure that forms a channel 104, a liquid storage chamber, and / or a reaction chamber, and the like. And the second substrate are bonded to each other to form a flow path, a liquid storage chamber, and / or a reaction chamber in which a fluid can flow or be stored. At least one end of the flow path 104 is formed with a port 105 for sending and receiving fluid. Depending on the application, the port 106 can also be formed at the opposite end.

  In order to send the liquid into the microchannel 104 via the port 105, for example, as shown in FIG. 8, an adapter 114 is disposed at the opening of the port 105, and the liquid feeding tube 116 is connected to the adapter 114. Then, the liquid is supplied from a liquid supply tank (not shown) through the liquid supply tube 116. A plunger pump may be used for feeding this liquid.

  Plunger pumps have been developed and put into practical use as liquid pumps with high pressure resistance and high precision, mainly for liquid chromatograph applications. As one of the problems in improving the accuracy of the plunger pump, there are prevention of generation of bubbles in the pump chamber and removal of the generated bubbles. If air bubbles adhere to the pump chamber and the air bubbles cannot be removed, the liquid feeding accuracy is reduced. Various devices have been proposed for preventing the generation of bubbles and measures for removing the generated bubbles. For example, a liquid feed pump that can easily remove bubbles remaining or generated in a dead space in the pump chamber is described in Japanese Patent Application Laid-Open No. 9-292238 (Patent Document 1). A plunger pump that can be removed and has excellent liquid replacement properties is described in Japanese Patent Laid-Open No. 9-126119 (Patent Document 2).

  FIG. 9A is a schematic cross-sectional view showing the structure of the liquid feed pump described in Patent Document 1. FIG. Inside the pump head 118 is a pump chamber 120 made up of a columnar space extending in the vertical direction. A plunger 122 is inserted into the pump chamber 120 from below, and the plunger 122 can be moved up and down by a plunger drive mechanism 124 and a spring 126. The cross-sectional shape of the plunger 122 is similar to the cross-sectional shape of the pump chamber 120, but has an outer diameter slightly smaller than the inner diameter of the pump chamber. A seal mechanism 128 is disposed at the lower end of the pump chamber 120 so that the pump chamber 120 can maintain hermeticity against the vertical movement of the plunger 122. As shown in the figure, in the liquid delivery pump described in Patent Document 1, the liquid inlet 130 is disposed near the lower end of the pump chamber 120 and on the side of the pump chamber above the seal mechanism 128, A liquid outlet 132 is disposed at the upper end of the pump chamber 120. Accordingly, it is described that a liquid flow is easily generated from the lower side to the upper side of the pump chamber, bubbles are hardly generated, and the generated bubbles can be easily removed by a purge operation of the plunger. However, the liquid flow from the lower side to the upper side does not necessarily extend over the entire space generated between the wall surface of the pump chamber and the outer peripheral surface of the plunger, and as shown in FIG. 9B, the inlet 130 of the inflow conduit 136. On the other hand, air bubbles are likely to be generated in a portion behind the plunger 122, and the air bubbles generated in this portion are difficult to remove by a liquid flow. Even if the bubbles are removed, the bubbles are discharged from the outlet 132 at the upper end of the pump chamber through the outlet pipe 134 to the outside of the liquid feeding pump, but the outlet pipe 134 is connected to the liquid feeding tube 116 in FIG. Then, the bubbles are finally sent out to the microchannel 104 of the microchannel chip 100.

  The distance between the pump chamber wall surface and the plunger outer peripheral surface is designed to be as narrow as possible in order to prevent the generation of bubbles. However, when the pump chamber wall surface and the plunger outer peripheral surface come into contact with each other, there is another problem that dust is generated as the plunger moves. Moreover, the space | interval of a pump chamber inner wall surface and a plunger outer peripheral surface cannot necessarily be made narrow enough from the restriction | limiting of the mechanism components which comprise a pump, or an assembly precision. The common sense is that the distance between the wall surface of the pump chamber and the outer peripheral surface of the plunger is about 0.1 mm (100 μm). On the other hand, the size of a microchannel such as a microchannel chip may be several tens of μm or less. As described above, bubbles generated in the pump chamber are removed and sent out of the pump chamber. If it penetrates, it is expected to cause a serious obstacle such as the microchannel being blocked by bubbles.

  On the other hand, Patent Document 2 describes a plunger pump as shown in FIG. 10 in which an inflow pipe 136 connecting the outside and the inside of the pump chamber 120 is provided through the inside of the plunger 122 ′. In this pump, since the inflow conduit 136 is provided through the plunger 122 ′, the pump chamber 120 does not become a bag path, so that bubbles that enter the pump chamber 120 are separated from the discharged liquid along the flow of the liquid. It is discharged out of the pump together. Even in this plunger pump, the bubbles are discharged from the outlet 132 at the upper end of the pump chamber 120 through the outflow pipe 134 to the outside of the pump. Therefore, if the liquid feed pump is connected to the microchannel chip, the bubbles are finally Is sent to the microchannel chip.

  Further, even the plunger pump described in Patent Document 2 cannot generate a liquid flow in the space generated in the gap between the pump chamber wall surface and the plunger outer peripheral surface. FIG. 11 shows a state where the plunger 122 ′ is moved to the suction end (on the seal 128 side), and the liquid is introduced into the pump chamber 120 by another liquid feeding means (not shown) instead of the suction operation of the plunger 122 ′. It is a general | schematic sectional drawing which shows a mode that is doing. Because of the problem of the movement accuracy of the plunger 122 ′ and the seal 128 made of an elastic material such as rubber, the plunger front end surface cannot always be the same as the upper end surface of the seal. Protruding. Therefore, a space is generated in the gap between the wall surface of the pump chamber and the outer peripheral surface of the plunger, but the air there is not pushed out by the introduction of the liquid, and remains as a bubble forever, preventing accurate liquid feeding. It becomes.

  The pumps described in Patent Document 1 and Patent Document 2 are mainly used in liquid chromatographs. However, unlike a liquid chromatograph analyzer, when the liquid is fed to the microchannel chip, the amount of the liquid to be fed is extremely small, and higher liquid feeding accuracy may be required. The plunger and pump chamber of the pump used for feeding the liquid to the microchannel chip are small. For example, the internal volume of the pump chamber may be as small as 100 μL or less. The pump chamber is close to a narrow pipe rather than a space, and in such a micro space, the force exerted on the liquid is dominated by interfacial forces such as surface tension rather than gravity, and bubbles are more likely to be generated and attached. It tends to be easy. Therefore, it cannot be expected that air bubbles will naturally escape upward due to buoyancy.

  When liquid feeding is performed, the liquid chromatograph is used at a relatively high pressure of several MPa to several tens of MPa. On the other hand, in the case of a resin micro-channel chip or the like, there is a case where liquid feeding is performed at a low pressure of about several kPa due to a problem of mechanical strength. Therefore, it cannot be expected that bubbles generated under almost atmospheric pressure when liquid is introduced into the pump will be reduced in volume due to high pressure during liquid feeding.

  In the application of the micro-channel chip, the liquid feeding flow rate may be extremely small as 1 μL / min or less. Therefore, even a fine bubble whose volume is less than 1 μL greatly affects liquid feeding accuracy.

  In the liquid chromatograph, the plunger is reciprocated many times in order to continuously feed the liquid for a long time. That is, the suction and discharge of the liquid in the pump chamber is repeated. There is a possibility that bubbles may be removed by chance in this process. Further, it is possible to positively perform a purging operation (repetitive preliminary suction / protrusion operation by the plunger) to remove bubbles. However, in the application of the microchannel chip, a desired test is often completed with only a small amount of liquid accumulated in the pump chamber by one suction operation. The microchannel chip has a major feature in that various chemical reactions can be performed with only a very small amount of solution. It is uneconomical and unreasonable to waste a large amount of solution by a purging operation or the like, and the purging operation itself is difficult because a very small amount of solution is originally prepared.

As described above, when applying a conventional plunger-type pump to a very small amount of liquid feeding to a microchannel chip or the like,
(1) Air bubbles are easily generated in the pump chamber and difficult to remove.
(2) It cannot be expected that the volume of bubbles will be reduced by the liquid supply pressure.
(3) Even a small volume of air bubbles affects liquid feeding accuracy.
(4) The purge operation cannot be performed from the viewpoint of the amount of solution, and it is difficult to fill the pump chamber with liquid without bubbles by one suction operation; and
(5) If bubbles are sent to the microchannel chip, the microchannel may be blocked.
There are problems such as.
Japanese Patent Laid-Open No. 9-292381 Japanese Patent Laid-Open No. 9-126119

Accordingly, an object of the present invention is to provide a liquid feed pump capable of introducing a liquid without leaving a small number of bubbles in the pump chamber.
Another object of the present invention is to provide a liquid feeding method using the liquid feeding pump.

  As means for solving the above-mentioned problems, the invention according to claim 1 of the present invention includes a pump head having a seal member having a plunger through-hole at a lower end portion, and the seal member inside the pump head with the seal member as one end A pump chamber extending in the opposite direction, a liquid inlet disposed on the side of the pump chamber on the upper surface side of the seal member, and a side surface of the pump chamber opposite to the liquid inlet and the seal member The first liquid outlet disposed on the upper surface side, the second liquid outlet disposed at the upper end of the pump chamber in the direction opposite to the seal member, and the plunger through hole are inserted into the pump chamber. The liquid feed pump includes a plunger that moves forward and backward in the pump chamber in a vertical direction, and a plunger drive mechanism that moves the plunger forward and backward.

  According to the present invention, even if a bubble is generated in a portion behind the plunger with respect to the liquid inlet, the bubble can be easily discharged from the first liquid outlet on the opposite side of the liquid inlet to the outside of the pump chamber together with the liquid. Can be removed and discharged.

  According to a second aspect of the present invention, as a means for solving the above problem, the liquid inlet is connected to one end of a liquid inflow conduit having a first on-off valve in the middle, and the first The liquid outlet is connected to one end of a first liquid outlet pipe having a second on-off valve in the middle, and the second liquid outlet has a second liquid having a third on-off valve in the middle. The liquid feed pump according to claim 1, wherein the liquid feed pump is connected to one end of the outflow pipe.

  According to this invention, the air bubbles generated in the pump chamber by linking the opening / closing operations of the on-off valves are sent from the second liquid outflow pipe line to the liquid sending object (for example, the micro-channel chip), It can be effectively removed and discharged from the first liquid outflow conduit.

  According to a third aspect of the present invention, the other end of the liquid inflow conduit is connected to a solution supply tank, and the solution supply tank and the first on-off valve A liquid introduction pump in between, the other end of the first liquid outflow line connected to the solution supply tank or waste liquid tank, and the other end of the second liquid outflow line connected to the liquid supply It is a liquid feeding pump of Claim 2 connected to the target object.

  According to the present invention, it is possible to reuse the liquid that has flowed to remove bubbles without wasting it.

  According to a fourth aspect of the present invention, the other end of the liquid inflow conduit is connected to a syringe filled with a solution, and the other end of the first liquid outflow conduit is used as a means for solving the problem. The liquid feed pump according to claim 2, wherein an end of the second liquid outflow pipe is connected to a waste liquid tank, and the other end of the second liquid outflow pipe is connected to a liquid feed object.

  According to this invention, by using a solution-filled syringe instead of the solution supply tank and the liquid introduction pump, not only the configuration of the whole liquid feed pump can be simplified but also the expensive liquid introduction pump can be omitted. The cost of the entire liquid pump can also be reduced.

  According to a fifth aspect of the present invention, the third on-off valve is a three-way valve as a means for solving the above-mentioned problems, and a second liquid outflow pipe leading to a liquid feed object is provided at one valve outlet. The liquid delivery pump according to claim 2, wherein a third liquid outflow pipe leading to the solution supply tank or the waste liquid tank is connected to the other valve outlet.

  According to this invention, when the liquid in the pump chamber is filled while expelling the gas in the upper part of the pump chamber from the second liquid outlet and the second liquid outflow pipe, the excess gas is sent to the liquid sending object. Without any problem, the three-way valve allows the third liquid outflow line to escape to the waste liquid tank or the solution supply tank.

  According to a sixth aspect of the present invention, as a means for solving the problem, the liquid inlet and the first liquid outlet are at a height position corresponding to a minimum protruding height from the upper surface of the seal member of the plunger. It is a liquid feeding pump of Claim 1 arrange | positioned by these.

  According to this invention, the plunger does not descend to the inside of the through hole of the seal member, and the plunger tip always protrudes slightly from the upper surface of the seal. Although many bubbles are generated around the protruding portion of the plunger tip, the liquid inlet and the first liquid outlet are arranged at a position corresponding to the protruding height of the plunger tip. Bubbles generated around the protruding portion can be discharged and removed very easily from the first liquid outlet to the outside of the pump chamber by the liquid entering from the liquid inlet.

According to a seventh aspect of the present invention, as means for solving the problems, a pump head having a seal member having a plunger through-hole at a lower end portion, and the seal member inside the pump head with the seal member as one end. A pump chamber extending in the opposite direction; a liquid inlet disposed on the side of the pump chamber on the upper surface side of the seal member; and a side surface of the pump chamber opposite to the liquid inlet and the upper surface of the seal member A first liquid outlet arranged on the side, a second liquid outlet arranged at the upper end of the pump chamber in the direction opposite to the seal member, and the plunger through-hole inserted into the pump chamber, A plunger that moves forward and backward in the vertical direction in the pump chamber, and a plunger drive mechanism for moving the plunger forward and backward,
The liquid inlet is connected to one end of a liquid inflow conduit having a first on-off valve in the middle, the other end of the liquid inflow conduit is connected to a solution supply tank, and the solution supply tank A liquid introduction pump between the first on-off valve and
The first liquid outlet is connected to one end of a first liquid outlet having a second opening / closing valve in the middle, and the other end of the first liquid outlet is connected to a liquid supply tank. And any tank selected from the group consisting of waste liquid tanks,
The second liquid outflow port is connected to one end of a second liquid outflow pipe having a third on-off valve in the middle, and the other end of the second liquid outflow pipe is an object to be fed. A liquid feeding method using a liquid feeding pump connected to
(1) Open the first on-off valve 25 and the second on-off valve 27, close the third on-off valve 29,
(2) Operate the liquid introduction pump to send the liquid from the solution supply tank to the pump chamber, stop the operation of the liquid introduction pump after the tip of the liquid reaches the downstream of the second on-off valve,
(3) Open the first on-off valve and the third on-off valve, close the second on-off valve, and operate the liquid introduction pump again.
(4) When the leading end of the liquid reaches the downstream of the third on-off valve and further reaches the desired position of the liquid feed object, the liquid introduction pump is stopped, and the first on-off valve and the third on-off valve 29 are turned on. Close,
(5) A liquid feeding method including opening the third on-off valve 29, discharging the plunger by a plunger driving mechanism, and pressurizing and feeding the liquid in the pump chamber into the liquid feeding object.

  According to the present invention, the liquid is initially filled without bubbles in the closed volume of the pump chamber by linking the opening / closing operations of the first on-off valve, the second on-off valve, and the third on-off valve. As a result, it is possible to send only the liquid without bubbles to the liquid sending object.

  As a means for solving the above problem, an invention according to claim 8 of the present invention is a liquid feeding method using a liquid feeding pump in which the other end of the first liquid outflow pipe is connected to a solution supply tank. The operation of the liquid introduction pump is continued until the liquid front end fills the first liquid outflow conduit and reaches the solution supply tank in the step (2), and then stopped. It is a liquid feeding method.

  According to the present invention, when the liquid is reintroduced into the pump chamber, the first on-off valve and the third on-off valve are closed, the second on-off valve is opened, and the plunger is sucked (that is, lowered). Since the inside of the pump chamber has a negative pressure, the solution in the solution supply tank is sucked into the pump chamber from the first liquid outflow pipe. Since there are no longer any gas or bubbles in the first liquid outflow conduit 17, there is no fear of drawing bubbles into the pump chamber 7. Therefore, the liquid introduction pump is first used to fill the pump chamber with liquid, but it is not always necessary to use the liquid introduction pump from the second time.

  According to a ninth aspect of the present invention, as a means for solving the above-mentioned problems, the third on-off valve is a three-way valve, and a second liquid outlet pipe leading to a liquid feed object is provided at one valve outlet. And the other valve outlet is connected to a third liquid outflow line that leads to any tank selected from the group consisting of a solution supply tank and a waste liquid tank. Item 8. The liquid feeding method according to Item 7.

  According to this invention, when the liquid in the pump chamber is filled while expelling the gas in the upper part of the pump chamber from the second liquid outlet and the second liquid outflow pipe, the excess gas is sent to the liquid sending object. Without any problem, the three-way valve allows the third liquid outflow line to escape to the waste liquid tank or the solution supply tank.

  The invention according to claim 10 of the present invention as means for solving the above-mentioned problem is that, in the step (2), the plunger is lowered to the suction end and then the liquid introduction pump is operated. This is a liquid feeding method.

  According to this invention, it is most preferable to prevent the generation of bubbles by operating the liquid introduction pump after the plunger is in this state.

  According to the liquid feeding pump and the liquid feeding method of the present invention, even if bubbles are generated in the pump chamber of a small and high performance plunger pump, these bubbles can be discharged and removed very easily outside the pump chamber. It is possible to remove the generated bubbles and then fill the pump chamber with liquid to provide highly accurate and reliable liquid feeding for liquid feeding objects having a fine flow channel structure such as a micro flow channel chip. Can be possible.

  FIG. 1 is a schematic cross-sectional view showing the basic configuration of the liquid feed pump of the present invention. FIG. 2 is a schematic diagram showing an example of a preferable pipeline configuration of the liquid feed pump shown in FIG. FIG. 3 is a schematic sectional view taken along line III-III in FIG. FIG. 4 is a schematic sectional view showing a certain operation state of the liquid feed pump of the present invention. FIG. 5 is a partial schematic diagram of another embodiment of the conduit configuration shown in FIG. FIG. 6 is a schematic diagram showing a preferred configuration example for actually operating the liquid feed pump of the present invention.

  Please refer to FIG. FIG. 1 shows a basic configuration of a liquid feed pump 1 of the present invention. The liquid feed pump 1 of the present invention basically has a pump head 3 and a plunger drive mechanism 5 at the lower part thereof. A pump chamber 7 is disposed in the pump head 3 so as to extend in the longitudinal direction. A seal member 9 is disposed at the lower end of the pump chamber 7. The seal member 9 is provided with a through hole, and a plunger 11 is inserted into the through hole. The plunger 11 is configured such that the inside of the pump chamber 7 can be advanced and retracted in the vertical direction by the plunger drive mechanism 5. A liquid inflow conduit 13 is connected to the lower side of the side surface of the pump head 3, and the liquid inflow conduit 13 communicates with a liquid inlet 15 on the inner wall surface of the pump chamber 7. A first liquid outflow conduit 17 is connected to the lower side of the side surface of the pump head 3 on the opposite side of the liquid inflow conduit 13. The first liquid outflow conduit 17 is connected to the inner wall surface of the pump chamber 7. 1 liquid outlet 19. Therefore, it is preferable that the liquid inlet 15 and the first liquid outlet 19 are arranged in a 180 ° positional relationship, and the liquid inlet 15 and the first liquid outlet 19 are present at the same height. Further, a second liquid outflow pipe 21 is connected to the upper surface of the pump head 3, and the second liquid outflow pipe 21 communicates with the second liquid outflow outlet 23 on the ceiling surface of the pump chamber 7. ing.

  The seal member 9 itself used in the liquid delivery pump 1 of the present invention shown in FIG. 1 is known to those skilled in the art. For example, a conventional seal member as described in Patent Document 1 and Patent Document 2 is used. be able to. For example, the seal member 9 can be formed of a water-repellent synthetic resin such as Teflon (registered trademark), or a seal member made of other materials can be used.

  The plunger driving mechanism 5 itself used in the liquid feed pump 1 of the present invention shown in FIG. 1 is known to those skilled in the art. For example, a conventional plunger driving mechanism as described in Patent Document 1 and Patent Document 2 is used. Can be used. Further, as the plunger drive mechanism 5, a drive mechanism comprising a cam and a spring means (for example, a spring), a drive mechanism comprising a rotary actuator comprising a stepping motor, a drive mechanism comprising a hydraulic or hydraulic cylinder, and a drive mechanism comprising an air cylinder Any drive mechanism capable of reciprocal movement can also be used.

  FIG. 2 is a schematic diagram showing an example of a preferable pipeline configuration of the liquid feed pump shown in FIG. A first opening / closing valve 25 is disposed in the middle of the liquid inflow conduit 13, and a second opening / closing valve 27 is disposed in the middle of the first liquid outflow conduit 17. A third on-off valve 29 is disposed in the middle of the liquid outflow pipe 21. One end of the liquid inflow conduit 13 is connected to a solution supply tank 33 (see FIG. 2), and a liquid introduction pump 31 is disposed between the solution supply tank 33 and the first on-off valve. . As the liquid introduction pump 31, a tube pump, a gear pump, a diaphragm pump, or the like can be used. The liquid introduction pump 31 only needs to have a flow capacity sufficient to fill the liquid in the pump chamber 7 of the liquid feed pump 1 in several seconds to several minutes. The liquid introduction pump 31 may have a lower flow rate accuracy than the plunger pump, and may have a pulsating flow or the like. Therefore, an inexpensive pump can be used. Alternatively, a syringe or the like can be used instead of the solution supply tank and the liquid introduction pump. The terminal end of the first liquid outflow pipe 17 can be connected to, for example, a waste liquid tank 35 (see FIG. 2). Alternatively, the end of the first liquid outflow line 17 can be connected to the solution supply tank 33. In addition, the end of the second liquid outflow pipe 21 is connected to a liquid feeding object (not shown) such as a microchannel chip.

A liquid introduction procedure by the liquid feed pump 1 of the present invention having a pipeline configuration as shown in FIG. 2 will be described.
(1) First, the first on-off valve 25 and the second on-off valve 27 are opened, and the third on-off valve 29 is closed.
(2) After confirming that the plunger 11 has been lowered to the lowest end (that is, the suction end), the liquid introduction pump 31 is actuated to send the liquid 37 from the solution supply tank 33 to the pump chamber 7. To do. Along with the operation of the liquid introduction pump 31, the gas (usually air) originally contained in the liquid inflow conduit 13, the liquid introduction pump 31, and the first on-off valve 25 passes through the pump chamber 7 to the first liquid. It is expelled through the outflow line 17. Finally, as shown in FIG. 3, in the lower part of the pump chamber 7, the liquid 37 wraps around the plunger 11 and goes to the first liquid outlet 19 provided on the side opposite to the liquid inlet 15. And liquid flow will be generated. The operation of the liquid introduction pump 31 is continued until the liquid 37 fills the inside of the second on-off valve 27 and the tip of the liquid 37 passes through the second on-off valve 27, and then stopped. As a result, gas is most likely to remain, that is, in the lower part of the pump chamber 7 where bubbles are most likely to be generated (particularly, the outer peripheral surface on the side opposite to the liquid inlet 15 of the plunger 11), and the pump chamber 7 is filled with liquid without bubbles. be able to.
(3) Subsequently, the first on-off valve 25 and the third on-off valve 29 are opened, the second on-off valve 27 is closed, and the liquid introduction pump 31 is operated again. At this time, as shown in FIG. 4, the liquid 37 filled in the lower portion of the pump chamber 7 is pumped to the upper portion of the pump chamber 7 while expelling gas to the second liquid outflow conduit 21 through the second liquid outlet 23. Fill chamber 7. At this time, if it is not desired to flow excess gas to the liquid sending object (for example, a micro-channel chip), an appropriate switching valve or the like is provided downstream of the third on-off valve, and the gas is appropriately discharged to another pipe. Alternatively, as shown in FIG. 5, a three-way valve is used for the third on-off valve 29, and the three-way valve is switched so as to let the gas escape to the third outflow line (waste liquid line) 39. . When the inside of the third on-off valve 29 is filled with the liquid 37, the three-way valve is switched again so that the liquid flows through the second liquid outflow conduit 21 of the main flow. The terminal end of the third outflow pipe (waste liquid pipe) 39 can be connected to either the solution supply tank 33 or the waste liquid tank 35. The third outflow pipe (waste liquid pipe) 39 can also be used when replacing the liquid in the pump chamber.
(4) When the leading end of the liquid 37 reaches the downstream of the third on-off valve 29 and further reaches the desired position of the liquid feed object, the liquid introduction pump 31 is stopped, and the first on-off valve 25 and the third on-off valve The on-off valve 29 is closed. By the above operation, the liquid is filled without any bubbles in the volume closed by the first on-off valve 25, the second on-off valve 27, and the third on-off valve 29 with the pump chamber 7 as the center. Can do. In the above description, the plunger 11 is positioned at the suction end (the state moved to the position closest to the seal member 9 side) at the start of the operation. This state is most preferable for preventing the generation of bubbles. However, if desired, the plunger can be moved to the suction end at any timing of the operation procedure.
(5) When the introduction of the liquid 37 into the pump chamber 7 is completed as described above, the first on-off valve 25 and the second on-off valve 27 are closed, the third on-off valve 29 is opened, and the plunger drive mechanism 5 By causing the plunger 11 to perform a discharge operation (that is, a lifting operation), it is possible to pressurize and supply the liquid to the liquid supply object (for example, the microchannel of the microchannel chip).

  The liquid introduction procedure is such that the liquid is first bubbled into the closed pump chamber volume by the linked operation of the first on-off valve 25, the second on-off valve 27, and the third on-off valve 29. This is a necessary procedure when filling without a liquid. When the liquid is once filled in the pump chamber and there are no bubbles in the pump chamber, it is not always necessary to operate the liquid introduction pump 31 after the second time. . That is, the liquid can be reintroduced into the pump chamber only by the suction operation of the plunger 11.

  FIG. 6 shows an example of a pipe configuration for reintroducing liquid into the pump chamber only by the suction operation of the plunger 11. In the configuration shown in FIG. 6, the first liquid outflow pipe 17 is piped back to the solution supply tank 33 instead of the waste liquid tank. In this case, the end of the first liquid outflow pipe 17 must be arranged to be below the liquid level of the solution supply tank 33, that is, soaked in the solution. When the pipe line configuration shown in FIG. 6 is used, in the liquid introduction procedure (2), the liquid introduction is performed until the tip of the liquid 37 fills the first liquid outflow pipe 17 and reaches the solution supply tank 33. The operation of the pump 31 is continued and then stopped. Thus, when the liquid 37 is reintroduced into the pump chamber 7, the first on-off valve 25 and the third on-off valve 29 are closed, the second on-off valve 27 is opened, and the plunger 11 is aspirated (that is, lowered). ) When the plunger 11 is suctioned, the inside of the pump chamber 7 becomes negative pressure, so that the solution 37 in the solution supply tank 33 is sucked into the pump chamber 7 from the first liquid outflow pipe 17. Since there are no longer any gas or bubbles in the first liquid outflow conduit 17, there is no fear of drawing bubbles into the pump chamber 7.

  In the pipeline configuration shown in FIG. 6, a small pump with a small liquid feed flow rate or a low-life pump can be used as the liquid introduction pump 31. That is, when the flow rate is small at the time of initial liquid introduction, it takes time to introduce the liquid, but at the second and subsequent liquid reintroduction times, the liquid can be introduced at the suction speed of the liquid feed pump 1. In addition, the introduction of air-free liquid is only necessary once after the solution is exchanged or the piping is cleaned. Compared with the liquid feed pump 1 of the present invention, a tube pump (this pump has a tube A low-life pump such as known to be easily consumed can be used as the liquid introduction pump 31.

  The preferred embodiments of the liquid feed pump of the present invention have been described with specific examples. However, the liquid feed pump of the present invention is not limited to the illustrated embodiments. The illustrated embodiment is an example of the pipe configuration of the liquid feeding pump of the present invention. For example, it is not always necessary to discharge and feed the liquid from the second outflow pipe 21, and in some cases, the first outflow pipe may be used. It is also possible to configure a pipeline so that liquid can be fed from the path 17 to the liquid feeding object.

  The liquid feed pump of the present invention can be widely used not only in the μTAS region, but also in the field of instrument analysis where high-precision liquid feed control is required, such as a high performance liquid chromatograph. Therefore, the liquid delivery pump of the present invention can be suitably used effectively in various fields such as medicine, veterinary medicine, dentistry, pharmacy, life science, food, agriculture, fisheries, and police identification. In particular, the liquid feeding pump of the present invention is used as a liquid feeding control means to the microchannel chip in the fluorescent antibody method, in situ hybridization, etc., for immunological disease testing, cell culture, virus fixation, pathological examination, cytodiagnosis, biopsy tissue It can be used inexpensively in a wide range of areas such as diagnosis, blood test, bacterial test, protein analysis, DNA analysis, and RNA analysis.

It is a schematic sectional drawing which shows the basic composition of the liquid feeding pump of this invention. It is a schematic diagram which shows an example of the preferable pipe line structure of the liquid feeding pump shown by FIG. FIG. 3 is a schematic sectional view taken along line III-III in FIG. 1. It is a schematic sectional drawing which shows a certain operating state of the liquid feeding pump of this invention. FIG. 3 is a partial schematic diagram of another embodiment of the pipeline configuration shown in FIG. 2. It is a schematic diagram which shows the preferable structural example for actually drive | operating the liquid feeding pump of this invention. (A) is a top view of an example of the microchannel chip | tip by a prior art, (b) is sectional drawing along the bb line in (a). It is a schematic sectional drawing which shows an example of the prior art for sending in a liquid to the microchannel of the microchannel chip | tip shown by FIG. (A) is a partial schematic cross-sectional view of the liquid feeding pump described in Patent Document 1, and (b) is a schematic diagram illustrating a state in which the liquid is filled in the pump chamber of the liquid feeding pump. It is a partial outline sectional view of a plunger pump indicated in patent documents 2. It is a schematic diagram explaining the state with which a liquid is filled in the pump chamber of the plunger pump shown by FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid feed pump 3 Pump head 5 Plunger drive mechanism 7 Pump chamber 9 Seal member 11 Plunger 13 Liquid inflow conduit 15 Liquid inlet 17 First liquid outlet 19 First liquid outlet 21 Second Liquid outlet pipe 23 Second liquid outlet 25 First on-off valve 27 Second on-off valve 29 Third on-off valve 31 Liquid introduction pump 33 Solution supply tank 35 Waste liquid tank 37 Liquid 39 Third liquid outflow pipe

Claims (10)

A pump head having a seal member having a plunger through-hole at its lower end, a pump chamber extending in the opposite direction to the seal member inside the pump head with the seal member as one end, a side surface of the pump chamber and the seal A liquid inlet disposed on the upper surface side of the member, a first liquid outlet disposed on the upper surface side of the seal member on the side surface of the pump chamber opposite to the liquid inlet, and opposite to the seal member A second liquid outlet arranged at the upper end of the pump chamber in the direction, a plunger inserted into the pump chamber through the plunger through-hole and moving forward and backward in the pump chamber, and for moving the plunger forward and backward A liquid feed pump having a plunger drive mechanism. The liquid inlet is connected to one end of a liquid inflow conduit having a first on-off valve in the middle, and the first liquid outlet has a second on-off valve in the middle of the first liquid outlet. 2. The feed according to claim 1, wherein the second liquid outlet is connected to one end of a second liquid outflow pipe having a third on-off valve in the middle of the second liquid outlet. Liquid pump. The other end of the liquid inflow conduit is connected to a solution supply tank, and has a liquid introduction pump between the solution supply tank and the first on-off valve, and the other end of the first liquid outflow conduit The liquid feed pump according to claim 2, wherein an end of the liquid supply tank is connected to the solution supply tank or a waste liquid tank, and the other end of the second liquid outflow pipe is connected to a liquid feed object. The other end of the liquid inflow conduit is connected to a syringe filled with a solution, the other end of the first liquid outflow conduit is connected to a waste tank, and the second liquid outflow conduit The liquid feed pump according to claim 2, wherein the other end is connected to a liquid feed object. The third on-off valve is a three-way valve, a second liquid outflow line leading to a liquid feeding object is connected to one valve outlet, and a second liquid outlet connecting to a solution supply tank or a waste liquid tank is connected to the other valve outlet. 3. The liquid feed pump according to claim 2, wherein three liquid outflow pipes are connected. 2. The liquid feed pump according to claim 1, wherein the liquid inlet and the first liquid outlet are disposed at a height position corresponding to a minimum protrusion height from the upper surface of the seal member of the plunger. A pump head having a seal member having a plunger through-hole at its lower end, a pump chamber extending in the opposite direction to the seal member inside the pump head with the seal member as one end, a side surface of the pump chamber and the seal A liquid inlet disposed on the upper surface side of the member, a first liquid outlet disposed on the upper surface side of the seal member on the side surface of the pump chamber opposite to the liquid inlet, and opposite to the seal member A second liquid outlet arranged at the upper end of the pump chamber in the direction, a plunger inserted into the pump chamber through the plunger through-hole and moving forward and backward in the pump chamber, and for moving the plunger forward and backward And a plunger drive mechanism
The liquid inlet is connected to one end of a liquid inflow conduit having a first on-off valve in the middle, the other end of the liquid inflow conduit is connected to a solution supply tank, and the solution supply tank A liquid introduction pump between the first on-off valve and
The first liquid outlet is connected to one end of a first liquid outlet having a second opening / closing valve in the middle, and the other end of the first liquid outlet is connected to a liquid supply tank. And any tank selected from the group consisting of waste liquid tanks,
The second liquid outflow port is connected to one end of a second liquid outflow pipe having a third on-off valve in the middle, and the other end of the second liquid outflow pipe is an object to be fed. A liquid feeding method using a liquid feeding pump connected to
(1) Open the first on-off valve 25 and the second on-off valve 27, close the third on-off valve 29,
(2) Operate the liquid introduction pump to send the liquid from the solution supply tank to the pump chamber, stop the operation of the liquid introduction pump after the tip of the liquid reaches the downstream of the second on-off valve,
(3) Open the first on-off valve and the third on-off valve, close the second on-off valve, and operate the liquid introduction pump again.
(4) When the leading end of the liquid reaches the downstream of the third on-off valve and further reaches the desired position of the liquid feed object, the liquid introduction pump is stopped, and the first on-off valve and the third on-off valve 29 are turned on. Close,
(5) A liquid feeding method comprising opening the third on-off valve 29, discharging the plunger by a plunger driving mechanism, and pressurizing and feeding the liquid in the pump chamber into the liquid feeding object. The other end of the first liquid outflow pipe is a liquid feed method using a liquid feed pump connected to a solution supply tank, and in step (2), the tip of the liquid is the first liquid outflow pipe. The liquid feeding method according to claim 7, wherein the operation of the liquid introduction pump is continued until the path is filled and the solution supply tank is reached, and then stopped. The third on-off valve is a three-way valve, and a second liquid outlet pipe leading to a liquid sending object is connected to one valve outlet, and a solution supply tank and a waste liquid tank are connected to the other valve outlet. The liquid feeding method according to claim 7, wherein the third liquid outflow pipe leading to any tank selected from the group is connected. 8. The liquid feeding method according to claim 7, wherein in step (2), the liquid introduction pump is operated after the plunger is lowered to the suction end.

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