A high-precision liquid mass control device

Abstract

The present application discloses a high-precision liquid mass control device, which includes a weighing mechanism, a mixing barrel, and a liquid injection mechanism. The mixing barrel has a main liquid inlet pipe and an auxiliary liquid inlet pipe; the liquid injection mechanism includes: a hard pipe inserted into the main liquid inlet pipe; a first stop valve installed on the hard pipe; a liquid injection pipeline connecting a material source and the hard pipe, and there are multiple control branches arranged in parallel on the liquid injection pipeline, and control valves with different flow rates are arranged on each control branch; a syringe having a barrel body and an injection needle, and the injection needle is inserted into the auxiliary liquid inlet pipe; a second stop valve installed on the injection needle; a replenishing pipe, one end of which is connected to the lower part of the inner space of the syringe, and the other end is used to connect the corresponding material source; a third stop valve installed on the replenishing pipe; a piston rod assembly installed on the syringe; and an electric push rod for driving the piston rod assembly to move downward. The present application can achieve high-precision liquid mass control.

Description

Technical Field

[0001] The present invention relates to the field of liquid mixing, and particularly to a high-precision liquid mass control device. Background Art

[0002] In the industrial manufacturing process, it is necessary to mix multiple liquids. The traditional mixing method is to control the amount of added materials through an electronic scale. Specifically, it is to control the on-off of the valve on the feeding pipeline according to the value of the electronic scale. This feeding method requires setting a lead amount according to experience. The instability of the pressure at the liquid adding source will cause a large deviation and increase the number of times of mixing failure.

[0003] The patent document with the publication number CN 218890393 U discloses a semiconductor workpiece processing fluid on-line mixing system, which controls the amount of materials through a mass flow controller, and then sends the mixed solution to an on-line analyzer for detection. The detection result is sent to a control device to adjust control parameters as needed. This mixing device has a complex structure, a complicated control method, and is limited by the analysis of the on-line analyzer, with limitations on the type of mixed liquid. The overall applicability is poor, and a high-precision mixed liquid cannot be simply and directly obtained. Summary of the Invention

[0004] In view of the above problems, the present invention provides a high-precision liquid mass control device.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A high-precision liquid mass control device includes a weighing mechanism, a mixing barrel, and multiple liquid injection mechanisms all connected to the mixing barrel. Different liquid injection mechanisms are used to transport different liquids. The mixing barrel is placed on the weighing mechanism. The upper end of the mixing barrel has multiple groups of liquid inlet structures, and each liquid inlet structure is in one-to-one correspondence and cooperation with each liquid injection mechanism. Each group of liquid inlet structures includes a liquid inlet main pipe and a liquid inlet auxiliary pipe both communicating with the internal space of the mixing barrel;

[0007] The liquid injection mechanism includes:

[0008] A hard pipe inserted into the liquid inlet main pipe, with a gap between the hard pipe and the liquid inlet main pipe;

[0009] A first stop valve installed on the hard pipe;

[0010] A liquid injection pipeline having an inlet of the liquid injection pipeline and an outlet of the liquid injection pipeline. The inlet of the liquid injection pipeline is used to connect to the corresponding material source, and the outlet of the liquid injection pipeline is connected to the hard pipe. The liquid injection pipeline has multiple control branches arranged in parallel, and control valves are arranged on each control branch. The flow rates of the control valves on different control branches are different;

[0011] A syringe, having a barrel and an injection needle, the injection needle being inserted into the liquid inlet auxiliary tube, and there being a gap between the injection needle and the liquid inlet auxiliary tube;

[0012] A second stop valve, installed on the injection needle;

[0013] A liquid replenishing tube, one end of which is connected to the lower part of the inner space of the syringe, and the other end is used to connect to the corresponding material source;

[0014] A third stop valve, installed on the liquid replenishing tube;

[0015] A piston rod assembly, having a piston part and a rod part connected to each other, the piston part being slidably and sealingly installed in the syringe;

[0016] An electric push rod, cooperating with the rod part, for driving the piston rod assembly to move downward.

[0017] A working method of a high-precision liquid mass control device: The first liquid injection mechanism works. In the order from large flow rate to small flow rate, different control valves are opened in sequence. Each time a control valve is opened, the weighing mechanism records the weight in real time. Until the increased weight reaches the value range corresponding to the corresponding control valve, the corresponding control valve is closed. When the control valve with the smallest flow rate is closed, the electric push rod works to push the piston part downward, so that the liquid in the barrel is injected into the mixing barrel until the weighing mechanism records that the increased weight reaches the set value. For example, if there are two control branches, and the first liquid injection mechanism needs to inject Xg of liquid A. When working, first open the control valve with a large flow rate (at this time, other control valves are closed) for rapid liquid addition until the value shown by the weighing mechanism increases by (80.0% - 90.0%)Xg (in actual application, the specific percentage can be set according to needs). Then open the control valve with a small flow rate (at this time, other control valves are closed) for liquid addition until the value shown by the weighing mechanism increases to (99.0 - 99.9%)Xg (in actual application, the specific percentage can be set according to needs). Finally, close all control valves, and push the liquid A in the syringe into the mixing barrel through the electric push rod (at this time, the second stop valve is opened and the third stop valve is closed) until the value shown by the weighing mechanism increases to Xg, and the injection of the first liquid injection mechanism is completed. Then, close the second stop valve, open the third stop valve, and replenish liquid A into the barrel through the liquid replenishing tube.

[0018] According to the working mode of the first liquid injection mechanism, other liquid injection mechanisms work one by one (that is, after one liquid injection mechanism finishes injecting the corresponding liquid, another liquid injection mechanism injects the corresponding liquid) until all the liquids are injected.

[0019] In this application, by setting control valves with different flow rates and opening different control valves in the order from large to small flow rate during operation, the liquid filling efficiency can be effectively improved. Finally, the liquid in the syringe is pushed by an electric push rod into the mixing barrel to achieve the final precise injection, ensuring high-precision liquid quality control. Further, there is a gap between the hard pipe and the main liquid inlet pipe, and a gap between the injection needle and the auxiliary liquid inlet pipe. Such a setting makes the injection mechanism not affect the quality of the mixing barrel and can ensure high-precision liquid quality control.

[0020] During actual operation, the high-precision liquid quality control device further includes a bracket independent of the mixing barrel. The hard pipe is fixed to the bracket through a first connection part, and the cylinder body is fixed to the bracket through a second connection part.

[0021] During actual operation, there can be two injection mechanisms, one for transporting solute and the other for transporting solvent. There can be two or three control branches.

[0022] In one embodiment of the present invention, the injection mechanism further includes:

[0023] A first air pump;

[0024] A first airbag, installed on the outer side wall of the hard pipe. The first airbag is located between the hard pipe and the main liquid inlet pipe. The first airbag is connected to the first air pump through an air pipe. The first airbag is used to make the hard pipe and the main liquid inlet pipe fit tightly in a sealed manner;

[0025] A second air pump;

[0026] A second airbag, installed on the outer side wall of the injection needle. The second airbag is located between the injection needle and the auxiliary liquid inlet pipe. The second airbag is connected to the second air pump through an air pipe. The second airbag is used to make the injection needle and the auxiliary liquid inlet pipe fit tightly in a sealed manner.

[0027] During actual operation, after the liquid mixing is completed, the first air pump and the second air pump can work to make the first airbag and the second airbag expand. The first airbag makes the hard pipe and the main liquid inlet pipe fit tightly in a sealed manner, and the second airbag makes the injection needle and the auxiliary liquid inlet pipe fit tightly in a sealed manner, thereby blocking the gaps. The mixed liquid is in a closed space, which can prevent the volatilization of volatile liquids.

[0028] In actual operation, the first airbag and the second airbag can also be in an inflated state before mixing the liquids. After the last control valve (the control valve with the smallest flow rate) is closed, the injection mechanism causes the first airbag to contract, and then expands the first airbag again (the purpose is to eliminate the influence of the friction between the first airbag and the main liquid inlet pipe on the measurement accuracy of the weighing mechanism). When the electric push rod works, the second airbag first contracts, and after the electric push rod finishes working, the second airbag is expanded again. Such a setting can reduce the evaporation amount of the volatile liquid compared with expanding the two airbags at the end.

[0029] Furthermore, pressure gauges are provided inside both the first airbag and the second airbag. Before liquid injection, the pressure inside the two airbags is N. At this time, the first airbag is slightly in contact with the main liquid inlet pipe, and the second airbag is slightly in contact with the auxiliary liquid inlet pipe (when in slight contact, it can prevent the evaporation of the liquid, and the influence on the measurement accuracy of the weighing mechanism can be basically ignored). After the liquid injection is completed, the pressure inside the two airbags is M, and M is greater than N. At this time, the first airbag is in close contact with the main liquid inlet pipe, and the two have good sealing performance. The second airbag is in close contact with the auxiliary liquid inlet pipe, and the two have good sealing performance.

[0030] In one embodiment of the present invention, the electric push rod is located above the rod portion, and the movable rod of the electric push rod is used for contact cooperation with the rod portion. One end of the rod portion cooperating with the electric push rod is provided with a pressure sensor.

[0031] In one embodiment of the present invention, the electric push rod is located above the rod portion, and the movable rod of the electric push rod is used for contact cooperation with the rod portion. One end of the movable rod of the electric push rod cooperating with the rod portion is provided with a pressure sensor.

[0032] Before replenishing the material in the cylinder body, the movable rod of the electric push rod first moves upward to reset, then the second stop valve is closed, the third stop valve is opened, and liquid A is replenished into the cylinder body through the liquid replenishing pipe. At this time, the piston portion is pressed to drive the rod portion to move upward until the rod portion and the movable rod are in contact, and the pressure measured by the pressure sensor exceeds the set threshold value. At this time, the third stop valve is controlled to close.

[0033] In one embodiment of the present invention, the end of the liquid replenishing pipe far away from the cylinder body is connected to the liquid injection pipeline, and the connection point is between the control branch and the inlet of the liquid injection pipeline.

[0034] In one embodiment of the present invention, it further includes a housing, and the weighing mechanism, the mixing barrel and the injection mechanism are arranged inside the housing.

[0035] Installing the weighing mechanism, the mixing barrel and the injection mechanism in a relatively enclosed housing can prevent part of the liquid from evaporating into the workshop due to the existence of gaps during liquid injection.

[0036] In one embodiment of the present invention, a waste discharge pipe is provided on the housing.

[0037] Through the waste discharge pipe, a small amount of gas volatilized into the housing can be discharged outside the housing.

[0038] In one embodiment of the present invention, a section of the liquid injection pipeline connected to the hard pipe is a flexible corrugated pipe.

[0039] In one embodiment of the present invention, the lower end of the mixing barrel is provided with a discharge pipe, a valve is provided on the discharge pipe, the discharge pipe is communicated with an external conveying pipeline through a first pipeline, and the first pipeline is a flexible corrugated pipe.

[0040] The traditional pipeline connection method has insufficient flexibility. By setting the flexible corrugated pipe in this application, it is convenient to connect and prevent stress.

[0041] In one embodiment of the present invention, a control unit is further included, and the control unit is used to control the operation of multiple groups of liquid injection units according to the data of the weighing unit.

[0042] In actual use, the stop valve, control valve and valve can be electric control valves or pneumatic control valves.

[0043] The beneficial effects of the present invention are as follows: By setting control valves with different flow rates and opening different control valves in sequence from large flow rate to small flow rate during operation in this application, the liquid addition efficiency can be effectively improved, and finally, the liquid in the syringe is pushed by the electric push rod to be injected into the mixing barrel to achieve the final precise injection, ensuring high-precision liquid quality control. Further, there is a gap between the hard pipe and the main liquid inlet pipe, and there is a gap between the liquid injection needle and the auxiliary liquid inlet pipe. Such a setting makes the liquid injection mechanism not affect the quality of the mixing barrel and can ensure high-precision liquid quality control. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram of a high-precision liquid quality control device;

[0045] Figure 2 is Figure 1 an enlarged view of part A in

[0046] Figure 3 is another schematic diagram of a high-precision liquid quality control device.

[0047] Each reference numeral in the figure is:

[0048] 1. Weighing mechanism; 2. Mixing barrel; 21. Liquid inlet structure; 211. Main liquid inlet pipe; 212. Auxiliary liquid inlet pipe; 22. Discharge pipe; 221. Valve; 23. Flexible corrugated pipe; 3. Liquid injection mechanism; 31. Rigid pipe; 311. First stop valve; 312. First airbag; 32. Liquid injection pipeline; 32a. Inlet of the liquid injection pipeline; 32b. Outlet of the liquid injection pipeline; 321. Control branch; 3211. Control valve; 33. Syringe; 331. Barrel body; 332. Liquid injection needle; 3321. Second airbag; 333. Second stop valve; 34. Supplementary liquid pipe; 341. Third stop valve; 35. Piston rod assembly; 351. Piston part; 352. Rod part; 3521. Pressure sensor; 36. Electric push rod; 361. Movable rod; 37. First air pump; 38. Second air pump; 4. Delivery pipeline; 5. Housing; 51. Waste discharge pipe. Detailed implementation manners

[0049] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. Generally, the components of the embodiments of the present application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0050] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0051] In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0052] The present invention will be described in detail below with reference to the accompanying drawings.

[0053] As Figure 1 and 2As shown in the figure, a high-precision liquid mass control device includes a weighing mechanism 1, a mixing barrel 2, and multiple liquid injection mechanisms 3 all connected to the mixing barrel 2. Different liquid injection mechanisms 3 are used to transport different liquids. The mixing barrel 2 is placed on the weighing mechanism 1. The upper end of the mixing barrel 2 has multiple groups of liquid inlet structures 21, and each liquid inlet structure 21 is in one-to-one correspondence and cooperation with each liquid injection mechanism 3. Each group of liquid inlet structures 21 includes a main liquid inlet pipe 211 and an auxiliary liquid inlet pipe 212 that are both connected to the internal space of the mixing barrel 2;

[0054] The liquid injection mechanism 3 includes:

[0055] A rigid pipe 31 is inserted into the main liquid inlet pipe 211, and there is a gap between the rigid pipe 31 and the main liquid inlet pipe 211;

[0056] A first stop valve 311 is installed on the rigid pipe 31;

[0057] A liquid injection pipeline 32 has an inlet 32a and an outlet 32b of the liquid injection pipeline. The inlet 32a of the liquid injection pipeline is used to connect to the corresponding material source, the outlet 32b of the liquid injection pipeline is connected to the rigid pipe 31, and there are multiple control branches 321 arranged in parallel on the liquid injection pipeline 32. Control valves 3211 are arranged on each control branch 321, and the flow rates of the control valves 3211 on different control branches 321 are different;

[0058] A syringe 33 has a barrel 331 and an injection needle 332. The injection needle 332 is inserted into the auxiliary liquid inlet pipe 212, and there is a gap between the injection needle 332 and the auxiliary liquid inlet pipe 212;

[0059] A second stop valve 333 is installed on the injection needle 332;

[0060] A liquid replenishing pipe 34 has one end connected to the lower part of the internal space of the syringe 33 and the other end used to connect to the corresponding material source;

[0061] A third stop valve 341 is installed on the liquid replenishing pipe 34;

[0062] A piston rod assembly 35 has a piston part 351 and a rod part 352 connected to each other. The piston part 351 is slidably and sealingly installed in the syringe 33;

[0063] An electric push rod 36 cooperates with the rod part 352 and is used to drive the piston rod assembly 35 to move downward.

[0064] A working method of a high-precision liquid mass control device: The first liquid injection mechanism 3 works. In the order from large flow rate to small flow rate, different control valves 3211 are opened in sequence. Each time a control valve 3211 is opened, the weighing mechanism 1 records the weight in real time. When the increased weight reaches the value range corresponding to the control valve 3211, the corresponding control valve 3211 is closed. After the control valve 3211 with the smallest flow rate is closed, the electric push rod 36 works to push the piston part 351 downward, so that the liquid in the cylinder body 331 is injected into the mixing barrel 2 until the weighing mechanism 1 records that the increased weight reaches the set value. For example, if there are two control branches 321 and the first liquid injection mechanism 3 needs to inject Xg of liquid A. During operation, first open the control valve 3211 with a large flow rate (at this time, other control valves 3211 are closed) for rapid liquid injection until the value displayed by the weighing mechanism 1 increases by (80.0% - 90.0%)Xg (in actual use, the specific percentage can be set according to needs). Then open the control valve 3211 with a small flow rate (at this time, other control valves 3211 are closed) for liquid injection until the value displayed by the weighing mechanism 1 increases to (99.0 - 99.9%)Xg (in actual use, the specific percentage can be set according to needs). Finally, close all control valves 3211, and push the liquid A in the syringe 33 into the mixing barrel 2 through the electric push rod 36 (at this time, the second stop valve 333 is opened and the third stop valve 341 is closed) until the value displayed by the weighing mechanism 1 increases to Xg, and the liquid injection of the first liquid injection mechanism 3 is completed. Then, close the second stop valve 333 and open the third stop valve 341, and replenish liquid A into the cylinder body 331 through the liquid replenishing pipe 34.

[0065] According to the working mode of the first liquid injection mechanism 3, other liquid injection mechanisms 3 work one by one (that is, after one liquid injection mechanism 3 completes the injection of the corresponding liquid, another liquid injection mechanism 3 injects the corresponding liquid) until the injection of all liquids is completed.

[0066] In this application, by setting control valves 3211 with different flow rates and opening different control valves 3211 in the order from large flow rate to small flow rate during operation, the liquid injection efficiency can be effectively improved. Finally, the liquid in the syringe 33 is pushed into the mixing barrel 2 through the electric push rod 36 to achieve the final precise injection, ensuring high-precision liquid mass control. Further, there is a gap between the rigid pipe 31 and the main liquid inlet pipe 211, and there is a gap between the liquid injection needle 332 and the auxiliary liquid inlet pipe 212. Such a setting makes the liquid injection mechanism 3 not affect the quality of the mixing barrel 2 and can ensure high-precision liquid mass control.

[0067] In actual use, the high-precision liquid mass control device further includes a bracket independent of the mixing barrel 2 (omitted and not shown in the figure). The hard pipe 31 is fixed to the bracket through a first connection part (omitted and not shown in the figure), and the cylinder body 331 is fixed to the bracket through a second connection part (omitted and not shown in the figure).

[0068] In this embodiment, there can be two liquid injection mechanisms 3, one for transporting the solute and the other for transporting the solvent. There are two control branches 321.

[0069] As Figure 2 shown, in this embodiment, the liquid injection mechanism 3 further includes:

[0070] A first air pump 37;

[0071] A first airbag 312, installed on the outer side wall of the hard pipe 31. The first airbag 312 is located between the hard pipe 31 and the main liquid inlet pipe 211. The first airbag 312 is connected to the first air pump 37 through an air pipe. The first airbag 312 is used to make the hard pipe 31 and the main liquid inlet pipe 211 fit tightly;

[0072] A second air pump 38;

[0073] A second airbag 3321, installed on the outer side wall of the liquid injection needle 33, The second airbag 3321 is located between the liquid injection needle 332 and the auxiliary liquid inlet pipe 212. The second airbag 3321 is connected to the second air pump 38 through an air pipe. The second airbag 3321 is used to make the liquid injection needle 332 and the auxiliary liquid inlet pipe 212 fit tightly.

[0074] In actual use, after the liquid mixing is completed, the first air pump 37 and the second air pump 38 can work to make the first airbag 312 and the second airbag 3321 expand. The first airbag 312 makes the hard pipe 31 and the main liquid inlet pipe 211 fit tightly, and the second airbag 3321 makes the liquid injection needle 332 and the auxiliary liquid inlet pipe 212 fit tightly, so as to block the gap and keep the mixed liquid in a closed space, which can prevent the volatilization of volatile liquids.

[0075] In actual use, the first airbag 312 and the second airbag 3321 can also be in an expanded state before the liquid mixing. After the last control valve 3211 (the control valve 3211 with the smallest flow rate) is closed, the liquid injection mechanism 3 makes the first airbag 312 contract, and then makes the first airbag 312 expand (the purpose is to eliminate the influence of the friction force between the first airbag 312 and the main liquid inlet pipe 211 on the measurement accuracy of the weighing mechanism 1). When the electric push rod 36 works, the second airbag 3321 first contracts, and after the electric push rod 36 finishes working, the second airbag 3321 expands again. Such a setting can reduce the volatilization amount of volatile liquids compared with making the two airbags expand finally.

[0076] Further, pressure gauges are provided inside both the first airbag 312 and the second airbag 3321. Before liquid injection, the pressure inside the two airbags is N. At this time, the first airbag 312 is slightly in contact with the main liquid inlet pipe 211, and the second airbag 3321 is slightly in contact with the auxiliary liquid inlet pipe 212 (when in slight contact, it can prevent the volatilization of the liquid, and the influence on the measurement accuracy of the weighing mechanism 1 can be basically ignored). After the liquid injection is completed, the pressure inside the two airbags is M, where M is greater than N. At this time, the first airbag 312 is in close contact with the main liquid inlet pipe 211, and the two have good sealing performance. The second airbag 3321 is in close contact with the auxiliary liquid inlet pipe 212, and the two have good sealing performance.

[0077] As Figure 2 shown, in this embodiment, the electric push rod 36 is located above the rod portion 352. The movable rod 361 of the electric push rod 36 is used for contact and cooperation with the rod portion 352. One end of the rod portion 352 that cooperates with the electric push rod 36 is provided with a pressure sensor 3521. In actual use, it can also be that one end of the movable rod 361 of the electric push rod 36 that cooperates with the rod portion 352 is provided with a pressure sensor 3521.

[0078] Before replenishing the material in the cylinder body 331, the movable rod 361 of the electric push rod 36 first moves upward to reset, then the second cut-off valve 333 is closed, and the third cut-off valve 341 is opened. A liquid is replenished into the cylinder body 331 through the liquid replenishing pipe 34. At this time, the piston portion 351 is pressed to drive the rod portion 352 to move upward until the rod portion 352 contacts the movable rod 361, and the pressure measured by the pressure sensor 3521 exceeds the set threshold. At this time, the third cut-off valve 341 is controlled to close.

[0079] As Figure 1 shown, in this embodiment, the end of the liquid replenishing pipe 34 away from the cylinder body 331 is connected to the liquid injection pipeline 32, and the connection point is between the control branch 321 and the inlet 32a of the liquid injection pipeline.

[0080] As Figure 1 shown, in this embodiment, a section of the liquid injection pipeline 32 connected to the rigid pipe 31 is a flexible corrugated pipe 23. The lower end of the mixing barrel 2 is provided with a discharge pipe 22. A valve 221 is provided on the discharge pipe 22. The discharge pipe 22 is connected to an external conveying pipeline 4 through a first pipeline, and the first pipeline is a flexible corrugated pipe 23.

[0081] The traditional pipeline connection method lacks flexibility. In this application, by providing the flexible corrugated pipe 23, it is convenient to connect and prevent stress.

[0082] In this embodiment, it further includes a control unit (omitted and not shown in the figure). The control unit is used to control the operation of multiple groups of liquid injection units according to the data of the weighing unit.

[0083] In actual use, the cut-off valve, the control valve 3211, and the valve 221 can be electric control valves or pneumatic control cut-offs.

[0084] In actual use, such as Figure 3 shown, the high-precision liquid mass control device further includes a housing 5, a weighing mechanism 1, a mixing barrel 2, and a liquid injection mechanism 3 are arranged in the housing 5, and the housing 5 is provided with a waste discharge pipe 51. Installing the weighing mechanism 1, the mixing barrel 2, and the liquid injection mechanism 3 in the relatively closed housing 5 can prevent part of the liquid from volatilizing into the workshop due to the existence of gaps during filling, and a small amount of gas that volatilizes into the housing 5 can be discharged outside the housing 5 through the waste discharge pipe 51.

[0085] The above are only the preferred embodiments of the present invention, and thus do not limit the patent protection scope of the present invention. Any equivalent structural transformation made by using the content of the specification and drawings of the present invention, directly or indirectly applied in other related technical fields, shall be included in the protection scope of the present invention by the same token.

Claims

1. A method for achieving high-precision liquid mass control, characterized in that It is implemented by a high-precision liquid mass control device, which includes a weighing mechanism, a mixing barrel, and multiple liquid injection mechanisms all connected to the mixing barrel. Different liquid injection mechanisms are used to transport different liquids. The mixing barrel is placed on the weighing mechanism. The upper end of the mixing barrel has multiple groups of liquid inlet structures, and each liquid inlet structure is in one-to-one correspondence and cooperation with each liquid injection mechanism. Each group of liquid inlet structures includes a main liquid inlet pipe and an auxiliary liquid inlet pipe that are both communicated with the internal space of the mixing barrel; The liquid injection mechanism includes: A hard pipe inserted into the main liquid inlet pipe, with a gap between the hard pipe and the main liquid inlet pipe; A first stop valve installed on the hard pipe; A liquid injection pipeline with an inlet of the liquid injection pipeline and an outlet of the liquid injection pipeline. The inlet of the liquid injection pipeline is used to connect to the corresponding material source, and the outlet of the liquid injection pipeline is connected to the hard pipe. Multiple control branches are arranged in parallel on the liquid injection pipeline, and control valves are arranged on each control branch. The flow rates of the control valves on different control branches are different; A syringe with a barrel and an injection needle. The injection needle is inserted into the auxiliary liquid inlet pipe, and there is a gap between the injection needle and the auxiliary liquid inlet pipe; A second stop valve installed on the injection needle; A replenishing pipe, one end of which is connected to the lower part of the internal space of the syringe, and the other end is used to connect to the corresponding material source; A third stop valve installed on the replenishing pipe; A piston rod assembly with a piston part and a rod part connected to each other. The piston part is slidably and sealingly installed in the syringe; An electric push rod cooperating with the rod part for driving the piston rod assembly to move downward; The liquid injection mechanism further includes: A first air pump; A first airbag installed on the outer side wall of the hard pipe. The first airbag is located between the hard pipe and the main liquid inlet pipe, and the first airbag is connected to the first air pump through an air pipe. The first airbag is used to make the hard pipe and the main liquid inlet pipe be in sealing cooperation; A second air pump; A second airbag installed on the outer side wall of the injection needle. The second airbag is located between the injection needle and the auxiliary liquid inlet pipe, and the second airbag is connected to the second air pump through an air pipe. The second airbag is used to make the injection needle and the auxiliary liquid inlet pipe be in sealing cooperation; The method for achieving high-precision liquid mass control is as follows: The first liquid injection mechanism works. In the order from large flow rate to small flow rate, different control valves are opened in sequence. Each time a control valve is opened, the weighing mechanism records the weight in real time until the increased weight reaches the value range corresponding to the control valve, then the corresponding control valve is closed. After the control valve with the smallest flow rate is closed, the electric push rod works to push the piston part downward to inject the liquid in the barrel into the mixing barrel until the weighing mechanism records that the increased weight reaches the set value. Among them, the first airbag and the second airbag are in an inflated state before mixing. After the last control valve of the liquid injection mechanism is closed, the first airbag contracts, and then the first airbag expands again to eliminate the influence of the friction force between the first airbag and the main liquid inlet pipe on the measurement accuracy of the weighing mechanism. When the electric push rod of the liquid injection mechanism works, the second airbag first contracts, and after the electric push rod finishes working, the second airbag expands again; According to the working mode of the first liquid injection mechanism, other liquid injection mechanisms work one by one until all the liquids are filled.

2. The method for realizing high-precision liquid mass control according to claim 1, wherein The electric push rod is located above the rod portion. The movable rod of the electric push rod is used for contact cooperation with the rod portion. One end of the rod portion cooperating with the electric push rod is provided with a pressure sensor.

3. The method for realizing high-precision liquid mass control according to claim 1, wherein The electric push rod is located above the rod portion. The movable rod of the electric push rod is used for contact cooperation with the rod portion. One end of the movable rod of the electric push rod cooperating with the rod portion is provided with a pressure sensor.

4. The method for realizing high-precision liquid mass control according to claim 2 or 3, characterized in that, One end of the liquid replenishing pipe away from the cylinder body is connected to the liquid injection pipeline, and the connection point is between the control branch and the inlet of the liquid injection pipeline.

5. The method for realizing high-precision liquid mass control according to claim 1, wherein, It further includes a housing, and the weighing mechanism, the mixing barrel and the liquid injection mechanism are arranged in the housing.

6. The method for achieving high-precision liquid mass control according to claim 5, wherein, The housing is provided with a waste discharge pipe.

7. The method for realizing high-precision liquid mass control according to claim 1, characterized in that, A section of the liquid injection pipeline connected to the hard pipe is a flexible corrugated pipe.

8. The method for realizing high-precision liquid mass control according to claim 1, wherein, The lower end of the mixing barrel is provided with a discharge pipe, and a valve is arranged on the discharge pipe. The discharge pipe is communicated with an external conveying pipeline through a first pipeline, and the first pipeline is a flexible corrugated pipe.

9. The method for realizing high-precision liquid mass control according to claim 1, wherein, It further includes a control unit, and the control unit is used to control the operation of multiple groups of liquid injection units according to the data of the weighing unit.

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