High-precision liquid management system

Abstract

The invention relates to a high-precision liquid management system which comprises an air pressure control unit, a liquid adding valve group, a liquid supplementing valve group, an operation bottle group, a liquid supplementing bottle group and a liquid dispensing bottle group. Each operation bottle of the operation bottle group is in one-to-one correspondence with a liquid adding valve of the liquid adding valve group and a liquid supplementing valve of the liquid supplementing valve group; the operation bottles are sequentially connected with the corresponding liquid adding valves and the liquid preparation bottles through liquid adding pipes and are used for inputting liquid into the liquid preparation bottles; the operation bottle is sequentially connected with the corresponding liquid supplementing valve and the corresponding liquid supplementing bottle through a liquid supplementing pipe and is used for extracting liquid from the liquid supplementing bottle and supplementing the liquid into the operation bottle; the air pressure control unit comprises a positive pressure air path and a negative pressure air path, the two air paths are connected with each operation bottle through electromagnetic valves and respectively provide constant positive pressure or negative pressure for the operation bottles, and when the operation bottles have constant positive pressure, liquid can be quantitatively input into the liquid preparation bottles; when constant negative pressure exists in the operation bottle, liquid can be quantitatively extracted from the liquid supplementing bottle and supplemented into the operation bottle.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of liquid taking and adding devices in laboratories, and particularly relates to a high-precision liquid management system. BACKGROUND

[0002] With the rapid development of technologies in the fields of biology, medicine, chemistry and the like, the demand for high-throughput and high-precision liquid processing is increasing rapidly, and the traditional manual pipetting operation is low in efficiency and high in error rate, and thus is difficult to meet the requirements of standardization and repeatability. Therefore, the field of high-precision liquid management in laboratories is facing challenges. At present, high-precision liquid adding technologies mainly include contact pipetting and non-contact pipetting. The contact pipetting is driven by a piston and relies on the contact between a pipette tip and a liquid surface, and is suitable for sampling liquid of 1 muL or more. In the non-contact pipetting, (1) piezoelectric jet technology, such as 0.1 muL level distribution (error ±3%) realized by the Suzhou Medical and Engineering Institute of the Chinese Academy of Sciences, is used for single cell sorting; (2) aerosol jet technology, nL level technology developed by Shenzhen Microfluid Technology, but the stability is insufficient (batch CV>5%). SUMMARY

[0003] In view of the above problems, the application provides a high-precision liquid management system, which comprises a gas pressure control unit, a liquid adding valve group, a liquid supplementing valve group, an operation bottle group, a liquid supplementing bottle group and a liquid preparation bottle group. Each operation bottle of the operation bottle group is one-to-one corresponding to one liquid adding valve of the liquid adding valve group and one liquid supplementing valve of the liquid supplementing valve group. The operation bottle is connected to the corresponding liquid adding valve and liquid preparation bottle in sequence through a liquid adding pipe, and is used for inputting liquid to the liquid preparation bottle. The operation bottle is connected to the corresponding liquid supplementing valve and liquid supplementing bottle in sequence through a liquid supplementing pipe, and is used for extracting liquid from the liquid supplementing bottle to supplement into the operation bottle.

[0004] The gas pressure control unit comprises a positive pressure gas circuit and a negative pressure gas circuit, and both of the two gas circuits are connected to each operation bottle through an electromagnetic valve, and respectively provide a constant positive pressure or negative pressure for the operation bottle. When the operation bottle has a constant positive pressure, the liquid can be quantitatively input into the liquid preparation bottle. When the operation bottle has a constant negative pressure, the liquid can be quantitatively extracted from the liquid supplementing bottle to supplement into the operation bottle.

[0005] Optionally, the operation bottle group comprises a plurality of operation bottles, and two liquid level sensors are arranged on the outer side wall of each operation bottle. A lower limit liquid level sensor is arranged at the lower part of the operation bottle, and an upper limit liquid level sensor is arranged at the upper part of the operation bottle, and are respectively used for monitoring the liquid level in the operation bottle in real time.

[0006] Optionally, the liquid supplementing bottle group comprises a plurality of liquid supplementing bottles, and different kinds of liquid are filled in each liquid supplementing bottle. The liquid supplementing bottle group can provide a plurality of kinds of liquid for the operation bottle group and the liquid preparation bottle group, so as to meet different liquid preparation requirements and configure different solutions. The liquid supplementing pipe on the upstream side of the liquid supplementing valve can be connected to different liquid supplementing bottles, so that the operation bottle can receive the liquid supplementing from different liquid supplementing bottles.

[0007] Further, the cleaning liquid in the one liquid supplement bottle flows through the liquid supplement pipe, the operation bottle, the liquid adding pipe and the liquid preparation bottle, thereby cleaning the components.

[0008] Optionally, the liquid adding valve group comprises a plurality of liquid adding valves, each of which is in one-to-one correspondence with the operation bottle and the liquid adding pipe, and can control the opening and closing of the corresponding liquid adding pipe to realize the liquid supply from the operation bottle to the liquid preparation bottle.

[0009] The liquid supplement valve group comprises a plurality of liquid supplement valves, each of which is in one-to-one correspondence with the operation bottle and the liquid supplement pipe, and can control the opening and closing of the corresponding liquid supplement pipe to realize the liquid supply from the liquid supplement bottle to the operation bottle.

[0010] Optionally, the gas pressure control unit further comprises a vacuum regulating valve, an electric proportional valve and a micro flowmeter, the solenoid valves and the micro flowmeters are in one-to-one correspondence with the operation bottles; the upstream end of the positive pressure gas path is connected to a gas supply device, and the downstream side is connected to the electric proportional valve, which is then divided into a plurality of positive branch gas paths, each of which is connected to a corresponding solenoid valve; the upstream end of the negative pressure gas path is connected to a gas extraction pump or a vacuum pump, and the downstream side is connected to the vacuum regulating valve, which is then divided into a plurality of negative branch gas paths, each of which is connected to a corresponding solenoid valve.

[0011] The outlet of the solenoid valve is connected to the corresponding micro flowmeter and operation bottle through the total gas path, which can provide stable positive pressure or negative pressure for the operation bottle.

[0012] Further, the solenoid valve is a three-way solenoid valve, one inlet is connected to the positive branch gas path, and the other inlet is connected to the negative branch gas path.

[0013] Optionally, the liquid adding pipe is connected to a liquid measuring device, which comprises a bracket and a liquid measuring cylinder, the liquid measuring cylinder is a reverse conical body, which is large at the top and small at the bottom, the top of the liquid measuring cylinder is provided with an inlet, the center of the bottom is provided with an outlet, and a valve door is arranged at the outlet to receive the liquid of the liquid adding pipe and discharge the liquid in the liquid measuring cylinder into the liquid preparation bottle.

[0014] At least two laser emitters are arranged side by side on the bracket to detect the liquid level in the liquid measuring cylinder; the top of the liquid measuring cylinder is arranged on the bracket to keep the top surface of the liquid measuring cylinder horizontal.

[0015] Further, the upper part of the bracket is provided with a support ring, the inside of the support ring is hollow, the outer wall of the top of the liquid measuring cylinder is placed on the support ring, and the other parts of the liquid measuring cylinder pass through the support ring and are suspended.

[0016] The support ring is provided with two horizontal beams below, the two horizontal beams are parallel to each other and have the same height, the two ends of the horizontal beams are respectively detachably connected to the two vertical columns of the support, and the height of the horizontal beams is adjustable; a plurality of laser emitters are arranged on one horizontal beam and are evenly arranged along the length direction of the corresponding horizontal beam; a plurality of laser receivers are arranged on the other horizontal beam, and the positions of the laser receivers correspond to the positions of the laser emitters one by one.

[0017] Further, the position of the inlet is close to the edge of the top surface of the liquid measuring cylinder, liquid is input to one side of the liquid measuring cylinder, the inlet is arranged on the top surface with the center of the top surface as a center axis, and the horizontal beam is parallel to the center axis, so that the monitoring points of the plurality of laser emitters are arranged along the corresponding axis below the center axis. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 Fig. 1 is a structural schematic diagram of a high-precision liquid management system (1);

[0019] Figure 2 Fig. 2 is a schematic diagram of the high-precision liquid management system (2);

[0020] Figure 3 Fig. 3 is a schematic diagram of the high-precision liquid management system (3);

[0021] Figure 4 Fig. 4 is a schematic diagram of a liquid measuring device (1);

[0022] Figure 5 Fig. 5 is a schematic diagram of the liquid measuring device (2).

[0023] In the drawings, 1 is an operation bottle, 2 is a liquid adding valve, 3 is a liquid supplementing valve, 4 is a liquid adding pipe, 5 is a liquid supplementing pipe, 6 is a liquid preparation bottle, 7 is a liquid supplementing bottle, 8 is a lower limit liquid level sensor, 9 is an upper limit liquid level sensor, 10 is a vacuum regulating valve, 11 is an electric proportional valve, 12 is a micro flowmeter, 13 is an electromagnetic valve, 14 is a liquid measuring cylinder, 15 is a positive pressure gas circuit, 16 is an inlet, 17 is a laser emitter, 18 is a negative pressure gas circuit, and 19 is a horizontal beam. DETAILED DESCRIPTION

[0024] The embodiment provides a high-precision liquid management system, as shown in the drawings, which comprises a gas pressure control unit, a liquid adding valve group, a liquid supplementing valve group, an operation bottle group, a liquid supplementing bottle group and a liquid preparation bottle group. Figures 1-5 Each operation bottle 1 of the operation bottle group 1 corresponds to one liquid adding valve 2 of the liquid adding valve group 2 and one liquid supplementing valve 3 of the liquid supplementing valve group 3 in one-to-one correspondence, and the operation bottle 1 is sequentially connected to the corresponding liquid adding valve 2 and liquid preparation bottle 6 through the liquid adding pipe 4 for inputting liquid to the liquid preparation bottle 6; the operation bottle 1 is sequentially connected to the corresponding liquid supplementing valve 3 and liquid supplementing bottle 7 through the liquid supplementing pipe 5 for extracting liquid from the liquid supplementing bottle 7 to supplement into the operation bottle 1.

[0025] The air pressure control unit comprises a positive pressure air path and a negative pressure air path, both of which are connected to each operation bottle 1 through electromagnetic valves 13 to respectively provide constant positive pressure or negative pressure for the operation bottle 1, so that the operation bottle 1 can quantitatively input liquid into the liquid preparation bottle 6 when the operation bottle 1 has constant positive pressure, or quantitatively extract liquid from the liquid supplement bottle 7 and supplement into the operation bottle 1 when the operation bottle 1 has constant negative pressure.

[0026] The operation bottle 1 group comprises a plurality of operation bottles 1, and two liquid level sensors are arranged on the outer side wall of each operation bottle 1, a lower limit liquid level sensor 8 is arranged at the lower part of the operation bottle 1, and an upper limit liquid level sensor 9 is arranged at the upper part of the operation bottle 1, which are respectively used for monitoring the liquid level in the operation bottle 1 in real time.

[0027] If the liquid level in the operation bottle 1 is lower than the lower limit liquid level sensor 8, it indicates that the liquid in the bottle is less, and liquid needs to be extracted from the liquid supplement bottle 7 and supplemented into the operation bottle 1; when the operation bottle 1 is supplemented with liquid, if the liquid level reaches the upper limit liquid level sensor 9, the liquid supplement is stopped, and subsequent liquid supply to the liquid preparation bottle 6 can continue.

[0028] The liquid preparation bottle 6 group comprises a plurality of liquid preparation bottles 6, which are used to receive the quantitative liquid delivered by the operation bottle 1 and complete the liquid taking operation; the liquid adding pipe 4 on the downstream side of the liquid adding valve 2 can be connected to different liquid preparation bottles 6 to quantitatively provide liquid for one or more liquid preparation bottles 6. The liquid preparation bottle 6 can be various forms of containers for containing liquid in the biochemical field, such as a volumetric flask, a sample tube, a test tube, etc.

[0029] The liquid supplement bottle 7 group comprises a plurality of liquid supplement bottles 7, each of which contains different kinds of liquid, and can provide various liquids for the operation bottle 1 group and the liquid preparation bottle 6 group to meet different liquid preparation requirements and configure different solutions; the liquid supplement pipe 5 on the upstream side of the liquid supplement valve 3 can be connected to different liquid supplement bottles 7, so that the operation bottle 1 can receive liquid supplement from different liquid supplement bottles 7.

[0030] One of the liquid supplement bottles 7 contains cleaning liquid, and the process of the cleaning liquid flowing through the liquid supplement pipe 5, the operation bottle 1, the liquid adding pipe 4 and the liquid preparation bottle 6 is the process of cleaning each component.

[0031] The liquid adding valve 2 group comprises a plurality of liquid adding valves 2, each of which corresponds to an operation bottle 1 and a liquid adding pipe 4, and the liquid adding valve 2 can control the opening and closing of the corresponding liquid adding pipe 4 to realize the liquid supply from the operation bottle 1 to the liquid preparation bottle 6.

[0032] The liquid supplement valve 3 group comprises a plurality of liquid supplement valves 3, each of which corresponds to an operation bottle 1 and a liquid supplement pipe 5, and the liquid supplement valve 3 can control the opening and closing of the corresponding liquid supplement pipe 5 to realize the liquid supply from the liquid supplement bottle 7 to the operation bottle 1.

[0033] The gas pressure control unit further comprises a vacuum regulating valve 10, an electric proportional valve 11 and a micro flowmeter 12, an electromagnetic valve 13, the micro flowmeter 12 and the operation bottle 1 one-to-one corresponding; the upstream end of the positive pressure gas circuit 15 is connected with a gas supply device, the downstream side is connected with the electric proportional valve 11, then is divided into several positive sub-gas circuits, and each positive sub-gas circuit is connected with a corresponding electromagnetic valve 13; the upstream end of the negative pressure gas circuit 18 is connected with an air pump or a vacuum pump, the downstream side is connected with the vacuum regulating valve 10, then is divided into several negative sub-gas circuits, and each negative sub-gas circuit is connected with a corresponding electromagnetic valve 13.

[0034] The outlet of the electromagnetic valve 13 is connected with the corresponding micro flowmeter 12 and operation bottle 1 through the total gas circuit in turn, and can provide stable positive pressure or negative pressure for the operation bottle 1.

[0035] The electromagnetic valve 13 is a three-way electromagnetic valve 13, one inlet is connected with the positive sub-gas circuit, and the other inlet is connected with the negative sub-gas circuit.

[0036] The gas supply device can be a compressed air cylinder or an inert gas cylinder, and can provide gas for the operation bottle 1.

[0037] The present application abandons the traditional contact type pipetting, belongs to the non-contact type pipetting, compared with the piezoelectric jet and aerosol jet, the present application selects a cheap and easy to get, easy to control gas (gas pressure) control mode, the cost is lower, the control is easier, and the operation is simple. The present application provides constant positive pressure to the operation bottle 1, and the liquid in the operation bottle 1 is pressed out and flows to the liquid preparation bottle 6, that is, the flow in the liquid adding pipe 4 is constant, under the premise that the length of the liquid adding pipe 4 is constant, as long as the opening time of the liquid adding pipe 4 is controlled through the liquid adding valve 2, the volume of the liquid adding can be controlled. Similarly, constant negative pressure is provided to the operation bottle 1, and the liquid in the liquid supplementing bottle 7 is extracted into the operation bottle 1, that is, the flow in the liquid supplementing pipe 5 is constant, under the premise that the length of the liquid supplementing pipe 5 is constant, as long as the opening time of the liquid supplementing pipe 5 is controlled through the liquid supplementing valve 3, the volume of the liquid supplementing can be controlled.

[0038] Specifically, the electric proportional valve can accurately control the pressure of the output end, so as to ensure that the pressure reaching the operation bottle is always a constant value. The control pressure range of the electric proportional valve is 0-0.5Mpa, the pressure control repeatability is within ±0.5%, and the air pressure control sensitivity is within ±0.2%. The positive pressure gas path is divided into several parts through the electric proportional valve 11, and the positive pressure in each positive sub-gas path is equal, which provides pressure for the corresponding operation bottle 1. The positive sub-gas path is connected to the inlet of the corresponding electromagnetic valve 13, and the gas is output from the outlet of the electromagnetic valve 13 to the total gas path, and then passes through the corresponding micro flow meter 12. The micro flow meter 12 is always in an open state during system operation, can monitor the flow of the gas in real time, and then determine whether the positive pressure or the negative pressure is constant, so as to prevent the decrease of the liquid adding accuracy caused by the change of the air pressure due to the gas leakage and the like. The total gas path is finally inserted into the corresponding operation bottle 1 through the adapter, and provides constant positive pressure for the bottle, so as to press the liquid in the bottle out.

[0039] The negative pressure gas path provides negative pressure through the vacuum regulating valve 10, and the negative pressure is divided into several parts through several negative sub-gas paths. The negative sub-gas path is connected to the other inlet of the corresponding electromagnetic valve 13, and then communicates with the total gas path, so as to provide negative pressure for the corresponding operation bottle 1. The micro flow meter 12 also monitors. The three-way electromagnetic valve 13 switches which inlet to use according to the program instruction of the control device, and then controls whether the output gas is negative pressure or positive pressure, so as to make the operation bottle 1 in the liquid supplementing state or the liquid adding state.

[0040] In the present application, the air pressure state in each operation bottle 1 is a stable and controllable pressure environment. Each operation bottle 1 is connected to the liquid adding pipe 4 and the liquid supplementing pipe 5. The liquid adding pipe 4 is connected to the liquid preparation bottle 6 through the liquid adding valve 2, and the liquid supplementing pipe 5 is connected to the liquid supplementing bottle 7 through the liquid supplementing valve 3. When the stable positive pressure gas is introduced into the operation bottle 1, the system is in the liquid adding state, the liquid adding valve 2 connects the corresponding operation bottle 1 and the liquid preparation bottle 6, and the liquid in the operation bottle 1 is discharged into the corresponding liquid preparation bottle 6 through the liquid adding pipe 4. Under the stable pressure environment of the operation bottle 1, the liquid discharged per unit time is also a constant value under the action of the positive pressure. The liquid is accurately added by starting and stopping the liquid adding valve 2 (i.e. high-precision liquid switching valve). The liquid adding accuracy in this mode can be controlled to be less than 1% (1ml of single liquid adding), and this accuracy can realize the application scene of liquid automation processing in most laboratories.

[0041] When the signal of the lower limit liquid level sensor 8 beside the operation bottle 1 disappears, it indicates that the liquid level in the bottle has fallen below the minimum warning liquid level, triggering the system to automatically supplement the liquid. The electromagnetic valve 13 is switched from the positive pressure state to the vacuum pressure state, and the operation bottle 1 is in a micro-vacuum environment. The liquid supplement valve 3 corresponding to the operation bottle 1 is turned on, and the liquid in the liquid supplement bottle 7 is input into the operation bottle 1 through the liquid supplement pipe 5. As the liquid level in the operation bottle 1 rises, the liquid level reaches the position of the upper limit liquid level sensor 9, the sensor signal is connected, the liquid supplementing action stops, the electromagnetic valve 13 switches back to the positive pressure inlet, and the liquid supplement valve 3 is closed. The system returns to the standby liquid adding state.

[0042] When the system needs to be cleaned after multiple liquid additions or when different types of sample liquids need to be replaced, the pipeline and operation bottle 1 in the system need to be cleaned. Start the cleaning program, open the liquid supplement valve 3 corresponding to the liquid supplement bottle 7 filled with cleaning liquid, and switch the electromagnetic valve 13 to the positive pressure interface and negative pressure interface multiple times, so that the operation bottle 1 is intermittently in a positive pressure or negative pressure environment. When in negative pressure, the cleaning liquid enters the operation bottle 1 from the liquid supplement bottle 7. When in positive pressure, the cleaning liquid is discharged from the operation bottle 1. After multiple operations, the inside of the operation bottle 1 is cleaned.

[0043] According to different liquid adding requirements, different pipe diameters of the liquid adding pipe 4 can be replaced to adjust the liquid adding precision. For example, for micro high-precision liquid adding requirements, smaller inner diameter liquid adding pipes are used to achieve smaller liquid addition per unit time, thereby achieving higher liquid addition precision. The above functions and operations of the present application can be realized by using existing PLC controllers.

[0044] During the experiment, the inventors found that due to the fact that the liquid in the operation bottle 1 may have a small amount of dissolved gas when adding positive pressure gas, the gas is first dissolved in the liquid when the positive pressure gas is input into the operation bottle 1, and the liquid will not exert pressure until it is saturated with gas. Therefore, a small error is caused during liquid addition. The present application proposes the following solution to the above problem.

[0045] The liquid adding pipe 4 is connected to a liquid measuring device, which includes a bracket and a liquid measuring cylinder 14. The liquid measuring cylinder 14 is a reverse cone, large at the top and small at the bottom. The top of the liquid measuring cylinder 14 is provided with an inlet 16, and the center of the bottom is provided with an outlet. A switchable valve is arranged at the outlet for receiving liquid from the liquid adding pipe 4 and discharging liquid in the liquid measuring cylinder 14 into the liquid preparation bottle 6.

[0046] At least two laser emitters 17 are arranged side by side on the bracket for detecting the liquid level in the liquid measuring cylinder 14. The top of the liquid measuring cylinder 14 is arranged on the bracket to keep the top surface of the liquid measuring cylinder 14 horizontal.

[0047] Further, the upper part of the support is provided with a support ring, the inside of the support ring is hollow, the outer wall of the top of the liquid measuring cylinder 14 is placed on the support ring, and the other parts of the liquid measuring cylinder 14 pass through the support ring and are suspended;

[0048] The two beams 19 are provided below the support ring, the two beams are parallel to each other and have the same height, the two ends of the beams are detachably connected to the two columns of the support, and the height of the beams 19 is adjustable; a plurality of laser emitters 17 are arranged on one of the beams, and the plurality of laser emitters 17 are uniformly arranged along the length direction of the corresponding beam; a plurality of laser receivers are arranged on the other beam, and the positions of the laser receivers and the laser emitters correspond one by one. The liquid measuring cylinder is between the two beams.

[0049] The support can use a common support form, for example, the upper parts of four columns support the support ring, and the four columns form a square.

[0050] The position of the inlet 16 is close to the edge of the top surface of the liquid measuring cylinder 14, liquid is input to one side of the liquid measuring cylinder 14, the inlet 16 is arranged as a center axis with the diameter of the top surface where the center of the top surface of the liquid measuring cylinder 14 is located, and the beams 19 are parallel to the center axis, so that the monitoring points of the plurality of laser emitters 17 are arranged along the corresponding axes directly below the center axis.

[0051] The liquid measuring cylinder 14 receives the liquid delivered by the liquid adding pipe 4, and the volume of the liquid is accurately measured again in the liquid measuring cylinder 14, and then the liquid is input into the liquid preparation bottle 6. Specifically, the liquid measuring cylinder 14 is vertically arranged, and the top surface of the liquid measuring cylinder 14 and the beams 19 are horizontally arranged. Since the liquid measuring cylinder 14 is a reverse conical body, the volume of the liquid in the liquid measuring cylinder 14 can be adjusted by controlling the liquid level height in the liquid measuring cylinder 14. According to the volume of the liquid to be taken, the height of the beams 19 is adjusted so that the monitoring points of the laser emitters and the laser receivers are all at the target liquid level height. The liquid adding pipe 4 is connected to the inlet 16, liquid is input from the edge of one side of the liquid measuring cylinder 14, the liquid level in the liquid measuring cylinder 14 rises, and when the liquid level reaches a new height, on a micro level, the liquid level on the side close to the inlet 16 rises first, and the liquid level on the side far from the inlet 16 rises later, and after the liquid is uniformly distributed in the liquid measuring cylinder 14, the liquid surface in the liquid measuring cylinder 14 reaches a consistent height again. The liquid adding of the liquid adding pipe 4 to the inlet 16 can be in the form of dropwise addition, that is, one drop at a time, and time is reserved for the liquid level in the liquid measuring cylinder 14 to be uniformly distributed.

[0052] When the liquid level in the equivalent liquid cylinder 14 reaches the target liquid level immediately, but has not reached the target liquid level, the liquid drop is added into the inlet 16 of the liquid adding pipe 4, the laser emitted by the laser emitter close to the inlet 16 is affected by the liquid surface, the corresponding laser receiver detects the target liquid level, but other laser receivers do not detect the change of the laser; then the liquid level in the liquid measuring cylinder 14 is homogenized, the pair of laser emitters and laser receivers that first detect the target liquid level do not detect the liquid level at this time, at this time, the liquid should be continuously added. After adding a drop of liquid, the pair of laser emitters and laser receivers close to the inlet 16 first detect the target liquid level, but other laser emitters and laser receivers do not detect it, then the liquid level in the liquid measuring cylinder 14 is homogenized, the overall liquid level reaches the target liquid level, all laser emitters and laser receivers detect the target liquid level, at this time, the liquid adding valve 2 is closed, the liquid adding is stopped, and the target liquid volume is measured in the liquid measuring cylinder 14. The valve at the outlet of the liquid measuring cylinder 14 is opened, the internal liquid flows into the liquid preparation bottle 6, and then the inlet 16 is aligned to blow air into the inside of the liquid measuring cylinder 14, the liquid beads hanging on the inner wall are purged, and all the liquid in the liquid measuring cylinder 14 is discharged.

[0053] The liquid adding experiment results of the liquid management system are as follows:

[0054] Table 1 Liquid adding experiment results (I)

[0055]

[0056] The repeatability is that 50 repeated experiments are performed for each nominal capacity, the average value and the standard deviation of the actual capacity of each experiment are calculated, and the repeated precision (%) = (standard deviation / average value) x 100%.

[0057] In the above table, the actual capacity and the relative error of the capacity corresponding to each nominal capacity are the results of one experiment, and the repeated precision corresponding to each nominal capacity is the result of 50 experiments including the above one experiment. Since the data amount is large, it is not fully displayed here.

[0058] As can be seen from the above table, the liquid adding precision of the liquid management system provided by the application is high, the repeatability is also good, and the level of industrial application can be reached.

Claims

1. A high precision liquid management system, characterized by, The air pressure control unit, the liquid adding valve group, the liquid supplementing valve group, the operation bottle group, the liquid supplementing bottle group and the liquid preparation bottle group are included. Each operation bottle of the operation bottle group is one-to-one corresponding to one liquid adding valve of the liquid adding valve group and one liquid supplementing valve of the liquid supplementing valve group. The operation bottle is connected to the corresponding liquid adding valve and liquid preparation bottle in sequence through a liquid adding pipe, and is used for inputting liquid into the liquid preparation bottle. The operation bottle is connected to the corresponding liquid supplementing valve and liquid supplementing bottle in sequence through a liquid supplementing pipe, and is used for extracting liquid from the liquid supplementing bottle and supplementing the liquid into the operation bottle. The air pressure control unit includes a positive pressure air path and a negative pressure air path. Both of the two air paths are connected to each operation bottle through an electromagnetic valve, and respectively provide a constant positive pressure or negative pressure for the operation bottle. When the operation bottle has a constant positive pressure, the liquid can be quantitatively input into the liquid preparation bottle. When the operation bottle has a constant negative pressure, the liquid can be quantitatively extracted from the liquid supplementing bottle and supplemented into the operation bottle.

2. The high precision fluid management system of claim 1, wherein, The operation bottle group includes a plurality of operation bottles. Two liquid level sensors are arranged on the outer side wall of each operation bottle. A lower limit liquid level sensor is arranged on the lower part of the operation bottle, and an upper limit liquid level sensor is arranged on the upper part of the operation bottle, which are respectively used for monitoring the liquid level in the operation bottle in real time.

3. The high precision fluid management system of claim 1, wherein, The liquid supplementing bottle group includes a plurality of liquid supplementing bottles. Different kinds of liquid are filled in each liquid supplementing bottle, which can provide a plurality of kinds of liquid for the operation bottle group and the liquid preparation bottle group, so as to meet different liquid preparation requirements and configure different solutions. The liquid supplementing pipe on the upstream side of the liquid supplementing valve can be connected to different liquid supplementing bottles, so that the operation bottle can receive the liquid supplement from different liquid supplementing bottles.

4. The high precision fluid management system of claim 3, wherein, One of the liquid supplementing bottles is filled with cleaning liquid. The process that the cleaning liquid flows through the liquid supplementing pipe, the operation bottle, the liquid adding pipe and the liquid preparation bottle is the process of cleaning each component.

5. The high precision fluid management system of claim 1, wherein, The liquid adding valve group includes a plurality of liquid adding valves. The liquid adding valve is one-to-one corresponding to the operation bottle and the liquid adding pipe. The liquid adding valve can control the opening and closing of the corresponding liquid adding pipe, so as to realize the liquid supply from the operation bottle to the liquid preparation bottle. The liquid supplementing valve group includes a plurality of liquid supplementing valves. The liquid supplementing valve is one-to-one corresponding to the operation bottle and the liquid supplementing pipe. The liquid supplementing valve can control the opening and closing of the corresponding liquid supplementing pipe, so as to realize the liquid supply from the liquid supplementing bottle to the operation bottle.

6. The high precision fluid management system of claim 1, wherein, The air pressure control unit further includes a vacuum regulating valve, an electric proportional valve and a micro flowmeter. The electromagnetic valve and the micro flowmeter are one-to-one corresponding to the operation bottle. The upstream end of the positive pressure air path is connected to a gas supply device, and the downstream side is connected to the electric proportional valve, and then is divided into a plurality of positive branch air paths. Each positive branch air path is connected to the corresponding electromagnetic valve. The upstream end of the negative pressure air path is connected to an air pump or a vacuum pump, and the downstream side is connected to the vacuum regulating valve, and then is divided into a plurality of negative branch air paths. Each negative branch air path is connected to the corresponding electromagnetic valve. The outlet of the electromagnetic valve is connected to the corresponding micro flowmeter and operation bottle in sequence through a total air path, so as to provide stable positive pressure or negative pressure for the operation bottle.

7. The high precision fluid management system of claim 6, wherein, The electromagnetic valve is a three-way electromagnetic valve. One inlet is connected to the positive branch air path, and the other inlet is connected to the negative branch air path.

8. The high precision fluid management system of claim 1, wherein, The liquid adding pipe is connected to a liquid measuring device. The liquid measuring device includes a bracket and a liquid measuring cylinder. The liquid measuring cylinder is a reverse cone body, which is large at the top and small at the bottom. The top of the liquid measuring cylinder is provided with an inlet, and the center of the bottom is provided with an outlet. A valve door is arranged at the outlet, which is used for receiving the liquid of the liquid adding pipe and discharging the liquid in the liquid measuring cylinder into the liquid preparation bottle. The support is provided with at least two laser emitters arranged side by side for detecting the liquid level in the liquid measuring cylinder; the top of the liquid measuring cylinder is arranged on the support to keep the top surface of the liquid measuring cylinder horizontal.

9. The high precision fluid management system of claim 8, wherein, The upper part of the support is provided with a support ring, the inside of the support ring is hollow, the outer wall of the top of the liquid measuring cylinder is placed on the support ring, and the other parts of the liquid measuring cylinder pass through the support ring and are suspended; Two cross beams are arranged below the support ring, the two cross beams are parallel to each other and have the same height, the two ends of the cross beams are detachably connected to the two vertical columns of the support, and the height of the cross beams is adjustable; a plurality of laser emitters are arranged on one cross beam, and the plurality of laser emitters are uniformly arranged along the length direction of the corresponding cross beam; a plurality of laser receivers are arranged on the other cross beam, and the positions of the laser receivers correspond one by one to the positions of the laser emitters.

10. The high precision fluid management system of claim 9, wherein, The position of the inlet is close to the edge of the top surface of the liquid measuring cylinder, the inlet inputs liquid to one side of the liquid measuring cylinder, the inlet and the top surface of the liquid measuring cylinder are arranged around the center axis of the diameter of the top surface of the liquid measuring cylinder, and the cross beams are parallel to the center axis, so that the monitoring points of the plurality of laser emitters are arranged along the corresponding axes directly below the center axis.

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