CN117504964A - Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser - Google Patents

Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser Download PDF

Info

Publication number
CN117504964A
CN117504964A CN202311296082.4A CN202311296082A CN117504964A CN 117504964 A CN117504964 A CN 117504964A CN 202311296082 A CN202311296082 A CN 202311296082A CN 117504964 A CN117504964 A CN 117504964A
Authority
CN
China
Prior art keywords
filter element
chamber
tested
air pressure
standard
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311296082.4A
Other languages
Chinese (zh)
Inventor
吴胜勇
莫海峰
田启源
吴天春
李仁攀
李阳
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Chengdu Kaitu Medical System Technology Co ltd
Original Assignee
Chengdu Kaitu Medical System Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chengdu Kaitu Medical System Technology Co ltd filed Critical Chengdu Kaitu Medical System Technology Co ltd
Priority to CN202311296082.4A priority Critical patent/CN117504964A/en
Publication of CN117504964A publication Critical patent/CN117504964A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/01—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with flat filtering elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B01L3/0213—Accessories for glass pipettes; Gun-type pipettes, e.g. safety devices, pumps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B01L3/0217—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/14—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measurement of pressure
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N35/00—Automatic analysis not limited to methods or materials provided for in any single one of groups G01N1/00 - G01N33/00; Handling materials therefor
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N35/00—Automatic analysis not limited to methods or materials provided for in any single one of groups G01N1/00 - G01N33/00; Handling materials therefor
    • G01N35/10—Devices for transferring samples or any liquids to, in, or from, the analysis apparatus, e.g. suction devices, injection devices
    • G01N35/1009—Characterised by arrangements for controlling the aspiration or dispense of liquids

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Clinical Laboratory Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Fluid Mechanics (AREA)
  • Automatic Analysis And Handling Materials Therefor (AREA)

Abstract

The application relates to the technical field of pipettors and provides a method for improving liquid level detection and liquid sucking and discharging performance of a pipettor. According to the method, the filter element in the TIP head is used as the standard filter element, and the related operation parameters of the liquid dispenser are used as references, so that the type of the filter element to be detected in the TIP head can be effectively identified when the liquid dispenser is used later, and the movement speed of the piston matched with the filter element to be detected is calculated according to the type of the filter element to be detected, so that when the density of the filter element to be detected is different from that of the standard filter element, the air pressure change in the first chamber is kept consistent as much as possible, and further the accuracy of liquid level detection and liquid suction and discharge by using filter elements with different densities of the liquid dispenser is improved.

Description

Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser
Technical Field
The application relates to the technical field of pipettors, in particular to a method for improving liquid level detection and liquid sucking and draining performance of a pipettor.
Background
The statements in this section merely provide background information related to the present application and may not constitute prior art.
Currently, pneumatic pipettors on the market generally have functions of liquid level detection, pressure abnormality detection and the like, and the principle of the pneumatic pipettors is to acquire air pressure changes to judge the air pressure changes by depending on an internal air pressure sensor. Specifically, a TIP is connected to a TIP of the pipette, a piston is disposed inside the TIP, a chamber is formed between an end of the TIP and the piston, when the liquid level is actually detected, the pipette performs an air suction and exhaust action (i.e., controls the piston to move in the chamber), and air pressure change data in the chamber is acquired in real time by means of an air pressure sensor, so that the acquired air pressure change data is compared with a preset air pressure change threshold value, and whether the end of the TIP contacts the liquid level is judged.
In the related art, in order to enhance the performance of the pipette, the pipette generally uses a TIP head with a filter element, and at this time, the filter element further divides the chamber into a first chamber between the filter element and the piston and a second chamber between the filter element and an end of the TIP head, and when the pipette performs liquid level detection or aspirates liquid, air passes through the filter element and circulates between the first chamber and the second chamber.
However, because the density of the filter element existing in the TIP head is different in the market, there is a large difference in permeability of the filter element to air, and the larger the density of the filter element is, the worse the permeability is, and the smaller the density of the filter element is, the better the permeability is. On the basis, when the liquid dispenser executes the air suction or blowing action, the difference of the densities of the filter elements can cause the difference of the amounts of air entering and exiting the first cavity, so that the difference of the air pressure change in the first cavity is caused, therefore, if only one air pressure change threshold is set, when the density of the filter element in the TIP head is changed, the liquid level detection cannot be accurately carried out according to the air pressure change in the first cavity, and when the densities of the filter element in the TIP head are different, the accuracy of the liquid dispenser in the process of sucking and discharging liquid can be affected.
Disclosure of Invention
In view of this, the object of the present application is to provide a method for improving the liquid level detection and liquid sucking and draining performance of a liquid dispenser, which uses a filter element in a TIP head as a standard filter element and uses related operation parameters of the liquid dispenser as a reference, so that the type of a filter element to be detected in the TIP head can be effectively identified when the liquid dispenser is used later, and the movement speed of a piston adapted to the filter element to be detected can be calculated according to the type of the filter element to be detected, so that when the density of the filter element to be detected is different from that of the standard filter element, the air pressure change in the first chamber is kept as consistent as possible, and further, the accuracy of the liquid level detection and liquid sucking and draining of the liquid dispenser can be improved by using filter elements with different densities.
The purpose of the application is realized by the following technical scheme:
the method for improving the liquid level detection and liquid sucking and discharging performance of the liquid dispenser comprises a gun head and a TIP head connected to the gun head, wherein a piston is arranged in the gun head, a filter element is arranged in the TIP head, a first cavity is formed between the piston and the filter element, and the filter element is divided into a standard filter element and a filter element to be tested, and the method comprises the following steps:
s1, acquiring first air pressure change data in the first chamber when the filter element is the standard filter element, and taking the first air pressure change data as standard air pressure change data;
s2, acquiring second air pressure change data in the first cavity when the filter element is the filter element to be tested;
s3, comparing the second air pressure change data with the standard air pressure change data to judge whether the filter element to be tested is the standard filter element, and executing the step S4 if the filter element to be tested is not the standard filter element;
s4, calculating the movement speed of the piston matched with the current filter element to be tested according to the proportional relation between the standard filter element and the filter element to be tested.
In some possible embodiments, in step S4, the proportional relation between the standard filter element and the filter element to be tested includes a first proportional relation and a second proportional relation;
the first proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the pipettor executes the suction action, and is expressed as follows:
the second proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the liquid transfer device executes the blowing action, and is expressed as follows:
in the above formulas (1) and (2), V represents the volume of the first chamber in the initial state, n represents the amount of the substance of the air in the first chamber in the initial state, Δt represents the movement time of the piston, S represents the cross-sectional area of the first chamber, V 1 Representing the movement speed of the piston when the filter element is the standard filter element, v 2 Represents the movement speed of the piston when the filter element is the filter element to be tested, m 1 Represents the air flow rate in unit time of the standard filter element, m 2 And the air flow rate in unit time of the filter element to be tested is represented.
In some possible embodiments, the deriving of the first proportional relation is:
let the air flow rate in unit time of the standard filter element be m 1 Setting the air flow rate of the filter element to be tested in unit time as m 2 ；
The amount of material of the air entering the first chamber through the standard filter cartridge during Δt time is:
△n 1 ＝m 1 △t (3)，
the amount of material of the air entering the first chamber through the filter element to be tested is:
△n 2 ＝m 2 △t (4)；
as can be derived from the ideal gas state equation,
(P-△P 1 )(V+△V 1 )＝(n+△n 1 )RT (5)，
(P-△P 2 )(V+△V 2 )＝(n+△n 2 )RT (6)，
in the above formulas (5) and (6), P represents the gas pressure of the first chamber in the initial state, R represents the molar gas constant, T is the temperature, and ΔP 1 Indicating the air pressure change value of the first chamber in delta t time when the filter element is the standard filter element, delta P 2 Representing the air pressure change value of the first chamber within delta t time when the filter element is the filter element to be tested, delta V 1 Representing the volume change value of the first chamber within a time delta t, delta V, when the filter element is the standard filter element 2 Representing the volume change value of the first chamber in delta t time when the filter element is the filter element to be tested;
let the cross-sectional area of the first chamber be S, then there is:
△V 1 ＝v 1 △tS (7)，
△V 2 ＝v 2 ΔtS (8)，
let P-DeltaP 1 ＝P-ΔP 2 The following steps are:
the first proportional relation is obtained by substituting the above equations (3), (4), (7) and (8) into equation (9).
In some possible embodiments, the deriving of the second proportional relation is:
let the air flow rate in unit time of the standard filter element be m 1 Setting the air flow rate of the filter element to be tested in unit time as m 2 ；
The amount of material of the air flowing out of the first chamber through the standard filter cartridge during Δt time is:
Δn 1 ＝m 1 Δt (10)，
the amount of material of the air flowing out of the first chamber through the filter element to be tested is as follows:
Δn 2 ＝m 2 Δt (11)；
as can be derived from the ideal gas state equation,
(P+ΔP 1 )(V-ΔV 1 )＝(n-Δn 1 )RT (12)，
(P+ΔP 2 )(V-ΔV 2 )＝(n-Δn 2 )RT (13)，
in the above formulas (12) and (13), P represents the gas pressure of the first chamber in the initial state, R represents the molar gas constant, T represents the temperature, and ΔP 1 Indicating the air pressure change value of the first chamber in delta t time when the filter element is the standard filter element, delta P 2 Representing the air pressure change value of the first chamber within delta t time when the filter element is the filter element to be tested, delta V 1 Representing the volume change value of the first chamber within a time delta t, delta V, when the filter element is the standard filter element 2 Representing the volume change value of the first chamber in delta t time when the filter element is the filter element to be tested;
let the cross-sectional area of the first chamber be S, then there is:
ΔV 1 ＝v 1 ΔtS (14)，
ΔV 2 ＝v 2 ΔtS (15)，
let P+ΔP 1 ＝P+ΔP 2 The following steps are:
the second proportional relation is obtained by substituting the above formulas (10), (11), (14) and (15) into formula (16).
In some possible embodiments, in step S1, the first air pressure change data is obtained after the pipette performs an aspiration, an air blowing or a TIP-pricking operation.
In some possible embodiments, in step S2, the second air pressure variation data is obtained after the pipette performs an aspiration, an air blowing or a TIP-pricking operation.
The technical scheme of the embodiment of the application has at least the following advantages and beneficial effects:
according to the method, the filter element in the TIP head is used as the standard filter element, and the related operation parameters of the liquid dispenser are used as references, so that the type of the filter element to be detected in the TIP head can be effectively identified when the liquid dispenser is used later, and the movement speed of the piston matched with the filter element to be detected is calculated according to the type of the filter element to be detected, so that when the density of the filter element to be detected is different from that of the standard filter element, the air pressure change in the first chamber is kept consistent as much as possible, and further the accuracy of liquid level detection and liquid suction and discharge by using filter elements with different densities of the liquid dispenser is improved.
Drawings
FIG. 1 is a partial cross-sectional view of a pipette provided in some embodiments of the present application;
FIG. 2 is a waveform of air pressure within a first chamber of a pipette according to some embodiments of the present application using a standard filter cartridge and performing an aspiration and insufflation action;
FIG. 3 is a waveform of air pressure within a first chamber of a pipette provided in some embodiments of the present application using a cartridge to be tested that is not a standard cartridge and performing an aspiration and insufflation action;
fig. 4 is a waveform diagram of air pressure in the first chamber when the pipette according to some embodiments of the present application performs aspiration and blowing actions after using a cartridge to be tested that is not a standard cartridge and correcting the movement speed of the piston.
Icon: 10-gun head, 20-TIP head, 30-piston, 40-filter core and 50-first chamber.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be clearly and completely described in the following in conjunction with the specific embodiments.
As shown in fig. 1, a partial cross-sectional view of a known pipette generally includes a gun head 10 and a TIP head 20 connected to the gun head 10, further, a piston 30 is disposed inside the gun head 10, a filter cartridge 40 is disposed inside the TIP head 20, and a first chamber 50 is formed between the piston 30 and the filter cartridge 40. When the pipette performs an aspiration action, the piston 30 moves in a direction away from the cartridge 40 to suck air outside the first chamber 50 into the inside of the first chamber 50, and correspondingly, when the pipette performs a blowing action, the piston 30 moves in a direction toward the cartridge 40 to discharge air inside the first chamber 50 to the outside of the first chamber 50.
Meanwhile, the pipette may further include an air pressure sensor (not shown in the figure) and a control module (not shown in the figure), wherein the air pressure sensor is used for detecting air pressure inside the first chamber 50 and sending out air pressure detection information, and the control module is capable of receiving the air pressure detection information sent by the air pressure sensor and generating air pressure change data inside the first chamber 50 (i.e. air pressure change value of the first chamber 50 after the pipette performs actions such as air suction and air blowing).
However, as can be seen from the description of the related art, when the density of the filter element 40 inside the TIP head 20 is different during the actual use of such a pipette, the air pressure change inside the first chamber 50 is different each time the pipette performs the suction or blowing operation, and if only one air pressure change threshold is set, the liquid level detection cannot be accurately performed according to the air pressure change inside the first chamber 50, and the accuracy of the pipette in the suction and the discharge process is affected.
For this purpose, the filter element 40 inside the TIP head 20 is further divided into a standard filter element and a filter element to be tested, where the standard filter element refers to the filter element 40, which has a specific density known in advance and obtains corresponding operation parameters (to be described later) of the pipette after the actual application in the pipette, before the actual application of the pipette, so as to use the relevant operation parameters of the pipette corresponding to the standard filter element as a reference; the cartridge to be tested is referred to as cartridge 40 which is actually used by the pipette during subsequent use.
Secondly, the application provides a method for improving the liquid level detection and liquid sucking and discharging performance of a liquid dispenser, which comprises the following steps:
s1, acquiring first air pressure change data in the first chamber 50 when the filter element 40 is a standard filter element, and taking the first air pressure change data as standard air pressure change data.
It will be appreciated that in step S1, the first air pressure change data may be obtained by the pipette performing an aspiration, insufflation or TIP head 20 pricking operation.
Specifically, when the filter element 40 is a standard filter element, the air pressure value inside the first chamber 50 is detected by the air pressure sensor and sent to the control module, and then the pipette is controlled to perform the action of sucking, blowing or pricking the TIP head 20, in this process, the air pressure inside the first chamber 50 will change, after the pipette finishes the action of sucking, blowing or pricking the TIP head 20, the air pressure sensor detects the air pressure value inside the first chamber 50 again and sends the air pressure value to the control module, at this time, the control module can obtain the air pressure change value inside the first chamber 50 before and after the pipette performs the action of sucking, blowing or pricking the TIP head 20 according to the air pressure values sent by the air pressure sensor twice, and the air pressure change value is the first air pressure change data.
It should be noted that, the above-mentioned operation of the pipette to perform the pricking TIP head 20 refers to a process of connecting the TIP head 20 to the gun head 10 by the pipette driven by the Z-axis driving mechanism, and during the process of pricking the TIP head 20, air inside the first chamber 50 passes through the filter element 40 and flows out of the first chamber 50, so that the operation of the pipette to perform the pricking TIP head 20 may be equivalent to the operation of the pipette to perform the blowing operation.
On this basis, the liquid dispenser is provided with optimal liquid level detection and liquid sucking and discharging performance by setting relevant operation parameters of the liquid dispenser when the filter element 40 is a standard filter element, wherein the relevant operation parameters can comprise the movement speed of the piston 30.
S2, acquiring second air pressure change data in the first chamber 50 when the filter element 40 is the filter element to be tested.
It will be appreciated that in step S2, the second air pressure change data may also be obtained by performing the aspiration, insufflation or TIP head 20 pricking actions by the pipette. The method for acquiring the second air pressure change data is the same as the method for acquiring the first air pressure change data, and will not be described herein.
S3, comparing the second air pressure change data with the standard air pressure change data to judge whether the filter element to be tested is a standard filter element, and if the filter element to be tested is not the standard filter element, executing the step S4.
Specifically, with reference to the first air pressure change data, if the second air pressure change data is equal to the first air pressure change data, it is indicated that the filter element to be tested belongs to the standard filter element, and at this time, only the piston 30 of the liquid dispenser needs to move at a preset movement speed (that is, the movement speed of the piston 30 of the liquid dispenser when the filter element 40 is the standard filter element) so that the liquid dispenser performs the air suction or air blowing action, so that the liquid dispenser has the best liquid level detection and liquid suction and discharge performance.
Otherwise, if the second air pressure change data is not equal to the first air pressure change data, the filter element to be tested is not the standard filter element. Further, if the second air pressure change data is greater than the first air pressure change data, the filter element to be tested is a high-density filter element with density higher than that of the standard filter element, and if the second air pressure change data is less than the first air pressure change data, the filter element to be tested is a low-density filter element with density lower than that of the standard filter element. In this case, step S4 is performed.
S4, if the filter element to be tested is not the standard filter element, the control module calculates the movement speed of the piston 30 matched with the current filter element to be tested according to a proportional relation between the standard filter element and the filter element to be tested.
It can be understood that, when the filter element to be tested is not a standard filter element, the step S4 is executed, so that the movement speed of the piston 30 of the liquid dispenser can be corrected, and even if the filter element to be tested is not a standard filter element, the air pressure change in the first chamber 50 can be kept as consistent as possible with the air pressure change in the first chamber 50 when the filter element 40 is a standard filter element during the air suction or air blowing action of the liquid dispenser, and on this basis, only one air pressure change threshold value is preset by the liquid dispenser, so that the liquid dispenser also has good liquid level detection and liquid suction and discharge performance when aiming at filter elements with different densities.
Specifically, in some embodiments of the present application, in step S4, the proportional relation between the standard filter element and the filter element to be tested includes a first proportional relation and a second proportional relation;
the first proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the pipette performs the suction action, that is, the movement speed of the piston 30 adapted to the current filter element to be tested when the pipette performs the suction action can be calculated according to the first proportional relation. Specifically, the first proportional relationship is expressed as:
correspondingly, the second proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the liquid dispenser performs the blowing action, that is, the movement speed of the piston 30 matched with the current filter element to be tested when the liquid dispenser performs the blowing action can be calculated according to the second proportional relation. Specifically, the second proportional relationship is expressed as:
in the above formulas (1) and (2), V represents the volume of the first chamber 50 in the initial state, n represents the amount of the substance in the air in the first chamber 50 in the initial state, and Δt represents the piston30, S denotes the cross-sectional area of the first chamber 50, v 1 Representing the rate of movement, v, of the piston 30 when the cartridge 40 is a standard cartridge 2 Representing the movement speed, m, of the piston 30 when the cartridge 40 is the cartridge to be tested 1 Representing air flow rate per unit time of standard filter element, m 2 Indicating the air flow rate per unit time of the filter element to be tested.
It will be appreciated that due to V, n, Δt, S, v described above 1 、m 1 、m 2 The equal parameters are known parameters, so that the movement speed v of the piston 30 matched with the current filter element to be tested when the liquid dispenser executes suction and blowing can be obtained through the first proportional relation and the second proportional relation 2 On this basis, when the pipette performs the aspiration or the blowing action, the piston 30 of the pipette is only required to move at the calculated movement speed within Δt time, so that the air pressure change in the first chamber 50 is kept as consistent as possible in the case that the filter element to be tested is not a standard filter element.
In some embodiments of the present application, the derivation of the first proportional relationship is:
let the air flow rate in unit time of standard filter element be m 1 Let the air flow rate of the filter element to be measured in unit time be m 2 The method comprises the steps of carrying out a first treatment on the surface of the The amount of material of the air that enters the first chamber 50 through the standard filter cartridge during the Δt time is:
Δn 1 ＝m 1 Δt (3)。
the amount of material of the air entering the first chamber 50 through the cartridge to be tested is:
Δn 2 ＝m 2 Δt (4)。
it will be appreciated that when the pipette performs an aspiration action, the piston 30 will move away from the cartridge 40, the volume of the first chamber 50 will increase, and air outside the first chamber 50 will pass through the cartridge 40 into the first chamber 50, but due to the presence of the cartridge 40 the rate of change of the substance of the air inside the first chamber 50 is much smaller than the rate of change of the volume of the first chamber 50, so, according to the ideal gas state equation, in order to keep the air inside the first chamber 50 in equilibrium, there will be a tendency for the air pressure inside the first chamber 50 to drop, so that it is possible to:
(P-ΔP 1 )(V+ΔV 1 )＝(n+Δn 1 )RT (5)，
(P-ΔP 2 )(V+ΔV 2 )＝(n+Δn 2 )RT (6)，
in the above formulas (5) and (6), P represents the gas pressure of the first chamber 50 in the initial state, R represents the molar gas constant, T represents the temperature, and ΔP 1 Indicating the change in air pressure in first chamber 50 over a period of Δt, ΔP, when cartridge 40 is a standard cartridge 2 Indicating the change in air pressure of the first chamber 50 over a period of Δt, deltaV, when the cartridge 40 is the cartridge to be tested 1 Indicating the change in volume of first chamber 50 over Δt time for cartridge 40 to be a standard cartridge, Δv 2 Indicating the change in volume of first chamber 50 over a time Δt when cartridge 40 is the cartridge to be tested.
Let the cross-sectional area of the first chamber 50 be S, there are:
ΔV 1 ＝v 1 ΔtS (7)，
ΔV 2 ＝v 2 ΔtS (8)，
on the basis, in order to keep the air pressure change of the first chamber 50 as uniform as possible when the filter element to be tested is not a standard filter element and the pipettor executes the aspiration action, the filter element to be tested is made to be P-DeltaP 1 ＝P-ΔP 2 The following steps are:
the first proportional relation is obtained by substituting the above equations (3), (4), (7) and (8) into equation (9).
In some embodiments of the present application, the derivation of the second proportional relationship is:
let the air flow rate in unit time of standard filter element be m 1 Let the air flow rate of the filter element to be measured in unit time be m 2 ；
The amount of material of the air flowing out of the first chamber 50 through the standard filter cartridge during the Δt time is:
Δn 1 ＝m 1 Δt (10)，
the amount of material of the air flowing out of the first chamber 50 through the cartridge to be tested is:
Δn 2 ＝m 2 Δt (11)；
it will be appreciated that when the pipette performs a blowing action, the piston 30 will move in a direction approaching the cartridge 40, the volume of the first chamber 50 will decrease, and the air inside the first chamber 50 will flow out of the first chamber 50 through the cartridge 40, but because of the presence of the cartridge 40, the rate of change of the substance of the air inside the first chamber 50 is much smaller than that of the first chamber 50, so, according to the ideal gas state equation, in order to keep the air inside the first chamber 50 in an equilibrium state, the air pressure inside the first chamber 50 will have a rising trend, so that it is possible to:
(P+ΔP 1 )(V-ΔV 1 )＝(n-Δn 1 )RT (12)，
(P+ΔP 2 )(V-ΔV 2 )＝(n-Δn 2 )RT (13)，
in the above formulas (12) and (13), P represents the gas pressure of the first chamber 50 in the initial state, R represents the molar gas constant, T represents the temperature, and ΔP 1 Indicating the change in air pressure in first chamber 50 over a period of Δt, ΔP, when cartridge 40 is a standard cartridge 2 Indicating the change in air pressure of the first chamber 50 over a period of Δt, deltaV, when the cartridge 40 is the cartridge to be tested 1 Indicating the change in volume of first chamber 50 over Δt time for cartridge 40 to be a standard cartridge, Δv 2 Representing the volume change value of the first chamber 50 over Δt time when the cartridge 40 is the cartridge under test;
let the cross-sectional area of the first chamber 50 be S, there are:
ΔV 1 ＝v 1 ΔtS (14)，
ΔV 2 ＝v 2 ΔtS (15)，
on the basis, in order to keep the air pressure change of the first chamber 50 as consistent as possible when the filter element to be tested is not a standard filter element and the air blowing action is performed by the liquid dispenser, the air pressure change of the first chamber is controlled to be P+delta P 1 ＝P+ΔP 2 The following steps are:
the second proportional relation is obtained by substituting the above equations (10), (11), (14) and (15) into equation (16).
In order to more clearly and intuitively demonstrate the benefits of the methods provided herein, pipettes employing filter cartridges 40 of different densities were also tested.
As shown in fig. 2 to 4, fig. 2 shows a waveform of air pressure of the first chamber 50 when the standard filter element is used as the pipette and the suction and blowing actions are performed, fig. 3 shows a waveform of air pressure of the first chamber 50 when the pipette is used as the filter element to be tested other than the standard filter element and the suction and blowing actions are performed, and fig. 4 shows a waveform of air pressure of the first chamber 50 when the pipette is used as the filter element to be tested other than the standard filter element and the suction and blowing actions are performed after the movement speed of the piston 30 is corrected.
As can be seen from fig. 2 and 3, when the filter element to be tested is not a standard filter element and the movement speed of the piston 30 is not corrected, the air pressure variation value of the first chamber 50 is about 6 times that of the first chamber 50 corresponding to the standard filter element. As can be seen from fig. 4, by correcting the movement speed of the piston 30 of the liquid shifter when the filter element to be tested is not the standard filter element, the air pressure variation value of the first chamber 50 corresponding to the filter element to be tested is substantially consistent with the air pressure variation value of the first chamber 50 corresponding to the standard filter element shown in fig. 2.
The foregoing is merely a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and variations may be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims (6)

1. The method for improving the liquid level detection and liquid sucking and draining performance of the liquid dispenser comprises a gun head and a TIP head connected to the gun head, wherein a piston is arranged in the gun head, a filter element is arranged in the TIP head, and a first cavity is formed between the piston and the filter element.
S1, acquiring first air pressure change data in the first chamber when the filter element is the standard filter element, and taking the first air pressure change data as standard air pressure change data;
s2, acquiring second air pressure change data in the first cavity when the filter element is the filter element to be tested;
s3, comparing the second air pressure change data with the standard air pressure change data to judge whether the filter element to be tested is the standard filter element, and executing the step S4 if the filter element to be tested is not the standard filter element;
s4, calculating the movement speed of the piston matched with the current filter element to be tested according to the proportional relation between the standard filter element and the filter element to be tested.
2. The method for improving the liquid level detection and the liquid sucking and discharging performance of a liquid dispenser according to claim 1, wherein in the step S4, the proportional relation between the standard filter element and the filter element to be tested includes a first proportional relation and a second proportional relation;
the first proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the pipettor executes the suction action, and is expressed as follows:
the second proportional relation is a proportional relation between the standard filter element and the filter element to be tested when the liquid transfer device executes the blowing action, and is expressed as follows:
in the above formulas (1) and (2), V represents the volume of the first chamber in the initial state, n represents the amount of the substance of the air in the first chamber in the initial state, Δt represents the movement time of the piston, S represents the cross-sectional area of the first chamber, V 1 Representing the movement speed of the piston when the filter element is the standard filter element, v 2 Represents the movement speed of the piston when the filter element is the filter element to be tested, m 1 Represents the air flow rate in unit time of the standard filter element, m 2 And the air flow rate in unit time of the filter element to be tested is represented.
3. The method for improving the liquid level detection and the liquid sucking and discharging performance of a liquid dispenser according to claim 2, wherein the deriving process of the first proportional relation is as follows:
let the air flow rate in unit time of the standard filter element be m 1 Setting the air flow rate of the filter element to be tested in unit time as m 2 ；
The amount of material of the air entering the first chamber through the standard filter cartridge during Δt time is:
Δn 1 ＝m 1 Δt (3)，
the amount of material of the air entering the first chamber through the filter element to be tested is:
Δn 2 ＝m 2 Δt (4)；
as can be derived from the ideal gas state equation,
(P-ΔP 1 )(V+ΔV 1 )＝(n+Δn 1 )RT (5)，
(P-ΔP 2 )(V+ΔV 2 )＝(n+Δn 2 )RT (6)，
in the above formulas (5) and (6), P represents the gas pressure of the first chamber in the initial state, R represents the molar gas constant, T is the temperature, and ΔP 1 Indicating the air pressure change value of the first chamber in delta t time when the filter element is the standard filter element, delta P 2 Indicating the filter element is the filter element to be treatedMeasuring the air pressure change value of the first chamber in delta t time and delta V of the filter element 1 Representing the volume change value of the first chamber within a time delta t, delta V, when the filter element is the standard filter element 2 Representing the volume change value of the first chamber in delta t time when the filter element is the filter element to be tested;
let the cross-sectional area of the first chamber be S, then there is:
ΔV 1 ＝v 1 ΔtS (7)，
ΔV 2 ＝v 2 ΔtS (8)，
let P-DeltaP 1 ＝P-ΔP 2 The following steps are:
the first proportional relation is obtained by substituting the above equations (3), (4), (7) and (8) into equation (9).
4. The method for improving the liquid level detection and the liquid sucking and discharging performance of a liquid dispenser according to claim 2, wherein the deriving process of the second proportional relation is as follows:
let the air flow rate in unit time of the standard filter element be m 1 Setting the air flow rate of the filter element to be tested in unit time as m 2 ；
The amount of material of the air flowing out of the first chamber through the standard filter cartridge during Δt time is:
Δn 1 ＝m 1 Δt (10)，
the amount of material of the air flowing out of the first chamber through the filter element to be tested is as follows:
Δn 2 ＝m 2 Δt (11)；
as can be derived from the ideal gas state equation,
(P+ΔP 1 )(V-ΔV 1 )＝(n-Δn 1 )RT (12)，
(P+ΔP 2 )(V-ΔV 2 )＝(n-Δn 2 )RT (13)，
in the above formulas (12) and (13), P represents the gas pressure of the first chamber in the initial state, R represents the molar gas constant, T represents the temperature, and ΔP 1 Indicating the air pressure change value of the first chamber in delta t time when the filter element is the standard filter element, delta P 2 Representing the air pressure change value of the first chamber within delta t time when the filter element is the filter element to be tested, delta V 1 Representing the volume change value of the first chamber within a time delta t, delta V, when the filter element is the standard filter element 2 Representing the volume change value of the first chamber in delta t time when the filter element is the filter element to be tested;
let the cross-sectional area of the first chamber be S, then there is:
ΔV 1 ＝v 1 △tS (14)，
△V 2 ＝v 2 △tS (15)，
let P+ [ delta ] P 1 ＝P+△P 2 The following steps are:
the second proportional relation is obtained by substituting the above formulas (10), (11), (14) and (15) into formula (16).
5. The method for improving the liquid level detection and the liquid sucking and discharging performance of a pipette according to claim 1, wherein in the step S1, the first air pressure change data is obtained after the pipette performs the actions of sucking, blowing or pricking the TIP head.
6. The method for improving the liquid level detection and the liquid sucking and discharging performance of a pipette according to claim 1, wherein in the step S2, the second air pressure change data is obtained after the pipette performs the actions of sucking, blowing or pricking the TIP head.
CN202311296082.4A 2023-10-09 2023-10-09 Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser Pending CN117504964A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311296082.4A CN117504964A (en) 2023-10-09 2023-10-09 Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311296082.4A CN117504964A (en) 2023-10-09 2023-10-09 Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser

Publications (1)

Publication Number Publication Date
CN117504964A true CN117504964A (en) 2024-02-06

Family

ID=89759564

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311296082.4A Pending CN117504964A (en) 2023-10-09 2023-10-09 Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser

Country Status (1)

Country Link
CN (1) CN117504964A (en)

Similar Documents

Publication Publication Date Title
JP4686100B2 (en) How to check the integrity of fluid movement
US7481097B2 (en) Method and device for measuring the surface tension of liquids
US7699455B2 (en) Inkjet recording apparatus
CN110170426B (en) Precise dispensing controller and dispensing control method thereof
US11525839B2 (en) Systems and methods for detecting a liquid level
US20160273951A1 (en) Method for controlling pipetting operations
CN117504964A (en) Method for improving liquid level detection and liquid sucking and discharging performance of liquid dispenser
CN114812739A (en) Method for accelerating liquid level detection of pneumatic pipettor and pneumatic pipettor
JP2002098706A (en) Quantitative suction tip and quantitative suction device
JP2000121649A (en) Automatic dispensing device
CN117428303B (en) Quick and accurate control method for proportional valve for welding pipeline gas supply
JP2711215B2 (en) Automatic dispensing device
CA2361798A1 (en) Fluid detection method
US20160363118A1 (en) Liquid supply system and method for controlling liquid supply system
JP5650881B2 (en) How to use the pressure sensor
JP2003063032A (en) Liquid adjusting device and ink jet recorder
JP2007315984A (en) Automatic analyzer
CN109187939B (en) Portable gas detection equipment pipeline cleaning device
JP2014065203A (en) Inkjet recording device
CN109466181B (en) Ink injection control method and system for ink box
JP2688163B2 (en) Dispensing device
CN103913280A (en) Method of determining full inflation of foldable bag and anesthesia machine controlled leakage test method
CN218955880U (en) Electromagnetic switching valve and piston type gas flow calibration system
US11484815B2 (en) Froth coalescing
WO2020183638A1 (en) Liquid chromatograph analysis system

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination