A single channel pipette calibration method

Abstract

The application discloses the technical field of pipettor and is a single-channel pipette gun calibration method, which comprises the following specific steps: precisely calculating the precision of the pipettor, and formulating the precision standards of the piston rod diameter D, the upper limit position screw pitch P of the push rod, the block position size L and the piston rod pressing head height h size, so as to ensure that the weighing calibration has consistency within the precision standard range; according to the precision standards of the machined parts in step one, the piston rod diameter D, the upper limit position screw pitch P of the push rod, the block position size L and the piston rod pressing head height h size are controlled, so that the machined parts have high interchangeability and assembly consistency, and the weighing calibration has consistency. The application can realize low cost and high efficiency by manufacturing a large number of standardized production tool clamps, and can improve the efficiency of large-scale standardized production.

Description

TECHNICAL FIELD

[0001] The present application relates to the pipette technical field, specifically a single-channel pipette gun calibration method. BACKGROUND

[0002] Pipettes are widely used in the field of life sciences, such as biology, pharmaceuticals, diagnostics, etc. According to the number of liquid taking nozzles, pipettes are divided into single-channel pipettes and multi-channel pipettes. In recent years, with the rapid development of biology, medicine, epidemic prevention and other industries, the application of single-channel pipettes is also becoming more and more widespread.

[0003] Single-channel pipettes can accurately transfer liquid from one container to another and are widely used in clinical diagnosis, biological testing, pharmaceutical research, chemical testing, environmental analysis and food safety; single-channel pipettes are precision measuring instruments that need to be accurately weighed and calibrated using precision weighing equipment before use; when calibrating in large quantities, not only do you need to buy a large number of expensive precision weighing equipment from abroad, but you also need to strictly control the temperature and humidity of the environment before calibration, and the operating personnel need to be trained to strict standards, and then manually weigh and calibrate; resulting in high cost and low efficiency of large-scale production calibration equipment. Therefore, a single-channel pipette gun calibration method is invented. SUMMARY

[0004] In view of the above and / or existing problems in a single-channel pipette gun calibration method, the present application is proposed.

[0005] Therefore, the purpose of the present application is to provide a single-channel pipette gun calibration method that can solve the above-mentioned existing problems.

[0006] To solve the above technical problems, according to one aspect of the present application, the present application provides the following technical solutions:

[0007] A single-channel pipette gun calibration method includes the following specific steps:

[0008] Step 1: Calculate the precision of the pipette accurately. Based on this, develop standards for the diameter D of the piston rod, the upper limit position of the push rod lead screw pitch P, the position size L of the stop block, and the height h of the piston rod pressing head size processing precision to ensure consistency in the precision standard range, so that the weighing calibration is consistent;

[0009] Step 2: According to the precision standards of the parts processed in step 1, control the diameter D of the piston rod, the upper limit position of the push rod lead screw pitch P, the position size L of the stop block, and the height h of the piston rod pressing head size to ensure that the parts have high interchangeability and assembly consistency, and to ensure that the weighing calibration is consistent;

[0010] Step three: make the standardized production required tooling fixture, control the parts assembly has a high consistency, and to ensure that the weighing calibration has a high consistency;

[0011] Step four: because the single channel pipette pipetting liquid volume is related to the piston rod diameter D and the piston rod stroke H, that is: V = πD2 H / 4, therefore, in the guarantee piston rod diameter D in gb1800-79 js5 tolerance range, control good piston rod H stroke can guarantee the single channel pipette pipetting liquid volume in the standard range, therefore, can make electronic height measuring mechanism to control the piston rod H stroke; when the piston rod stroke H is within ±0.05 tolerance, it can be guaranteed that the liquid volume of the single channel pipette is within the standard range;

[0012] Step five: take electronic height measuring mechanism as the reference, make multi-dimensional calibration mechanical hand, which is connected and controlled by computer to realize full-automatic grabbing, measuring and calibrating of single channel pipette mass production, so as to realize high consistency in single channel pipette mass production and make single channel pipette mass production within the standard range, thereby solving the problems of high cost and low efficiency of calibration equipment in mass production.

[0013] As a preferred scheme of the single channel pipette gun calibration method, the single channel pipette comprises a shell, a piston rod pressing head, a scale wheel knob, an upper limit position screw rod of a push rod, a stop block, a lower limit position block of the push rod, a piston rod push rod, a piston rod return spring, a piston rod sealing ring, a piston rod, a piston cylinder and a suction head, the bottom end of the shell is provided with the piston cylinder, the piston rod is sealed in the piston cylinder through the piston rod sealing ring, so that negative pressure or positive pressure is formed in the piston cylinder when the piston rod moves; the bottom end of the piston cylinder is provided with the suction head to suck or squeeze out liquid through the suction head.

[0014] As a preferred scheme of the single channel pipette gun calibration method, the top of the piston rod is provided with the piston rod return spring, and the piston rod return spring is located on the middle part of the shell, so that the top of the piston rod is always in contact with the bottom of the piston rod push rod.

[0015] As a preferred scheme of the single channel pipette gun calibration method, the piston rod push rod is provided with the stop block, and the piston rod push rod is slidingly connected to the top end of the shell, so that the piston rod push rod is pushed upward under the action of the piston rod return spring and stops moving when the stop block collides with the upper limit position screw rod of the push rod.

[0016] As a preferred scheme of the single-channel pipette calibration method, the piston rod push rod is fixed on the piston rod pressing head through the push rod upper limiting lead screw and the push rod lower limiting block, the piston rod pressing head is slidingly connected on the top end of the shell, the distance from the push rod upper limiting lead screw to the push rod lower limiting block is set as the piston rod stroke H, and the top end of the shell is rotationally connected with the scale wheel knob, and the inner cavity of the scale wheel knob is slidingly connected with the piston rod pressing head.

[0017] As a preferred scheme of the single-channel pipette calibration method, the single-channel pipette is arranged in the electronic height measuring mechanism.

[0018] The electronic height measuring mechanism comprises an electronic height measuring instrument, a slide rail, a height measuring probe, a column and a pipette profiling positioning clamp, the single-channel pipette is arranged in the pipette profiling positioning clamp, and the column is fixedly installed on the top left side of the pipette profiling positioning clamp.

[0019] As a preferred scheme of the single-channel pipette calibration method, one side of the column is fixedly installed with a slide rail, the electronic height measuring instrument is fixedly installed on the slide rail, and the height measuring probe is arranged on the electronic height measuring instrument so that the height measuring probe can contact the piston rod pressing head and measure the piston rod stroke H.

[0020] As a preferred scheme of the single-channel pipette calibration method, one side of the electronic height measuring mechanism is provided with a multi-dimensional calibration mechanical hand so as to automatically grab, measure and calibrate the single-channel pipette.

[0021] Compared with the prior art, the single-channel pipette calibration method has the following advantages:

[0022] 1. The required tooling fixture is mass-produced in a standardized manner, which not only has low cost and good effect, but also improves the mass production efficiency.

[0023] 2. The mass-produced products with high consistency are selected and weighed for calibration, which can realize the use of only one expensive and precise foreign weighing equipment, thereby greatly reducing the cost of purchasing a large number of expensive and precise foreign weighing equipment.

[0024] 3. The semi-automatic or automatic calibration equipment is made, which not only further reduces the cost investment, but also greatly improves the calibration efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The flowchart of the present application is shown in the figure;

[0026] Figure 2Structure state one of the present application is a front view schematic diagram;

[0027] Figure 3 Structure state two of the present application is a front view schematic diagram;

[0028] Figure 4 Piston rod of the present application is a front view schematic diagram;

[0029] Figure 5 Upper limit of the push rod of the present application is a front view schematic diagram;

[0030] Figure 6 Piston rod push rod of the present application is a front view schematic diagram;

[0031] Figure 7 Piston rod pressing head of the present application is a front view schematic diagram;

[0032] Figure 8 Piston rod pressing head, piston rod push rod and pipette profiling positioning fixture structure of the present application are a front view schematic diagram;

[0033] Figure 9 Single-channel pipette and electronic height measuring mechanism structure of the present application are a front view schematic diagram;

[0034] Figure 10 Overall structure of the present application is a front view schematic diagram.

[0035] In the figure: piston rod pressing head 100, scale wheel knob 101, push rod upper limit lead screw 102, stop block 103, push rod lower limit block 104, piston rod push rod 105, piston rod return spring 106, piston rod sealing ring 107, piston rod 108, piston cylinder 109, suction head 110, electronic height measuring instrument 200, slide rail 201, height measuring probe 202, stand column 203, pipette profiling positioning fixture 205, multi-dimensional calibration mechanical hand 300. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the present application more clear, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0037] The present application provides a single-channel pipette gun calibration method, please refer to Figures 1-10 , including specific steps as follows:

[0038] Step one: accurate calculation of the precision of the pipette, on this basis, the piston rod 108 diameter D, push rod upper limit position screw 102 pitch P, block 103 position size L, piston rod pressing head 100 height h size processing precision standard is formulated, to ensure that within the precision standard range, so that the weighing calibration has consistency; calculated that the piston rod diameter D must be processed according to gb1800-79 js5 standard; Push rod upper limit position screw pitch P cumulative tolerance must be processed according to ±0.05 tolerance; Block position size L, piston rod pressing head height h must be processed according to ±0.05; Can make the weighing calibration has consistency;

[0039] Step two: according to the precision standard of step one, the piston rod 108 diameter D, push rod upper limit position screw 102 pitch P, block 103 position size L, piston rod pressing head 100 height h size is controlled, such as controlling the piston rod diameter D within the gb1800-79 js5 tolerance range; Push rod upper limit position screw pitch P cumulative tolerance is within ±0.05; Block position size L, piston rod pressing head height h size processing tolerance is within ±0.05; To make the parts have high interchangeability, assembly consistency, and to ensure that the weighing calibration has consistency;

[0040] Step three: make the standard production required tooling fixture, control the parts assembly has high consistency, and to ensure that the weighing calibration has high consistency; Such as making pipette profile positioning fixture, so that the piston rod push rod and piston rod pressing head interference fit tight after the key size h1 tolerance is within ±0.05;

[0041] Step four: because the single channel pipette pipetting liquid volume is related to the piston rod 108 diameter D and piston rod stroke H, that is: V = πD2 H / 4, therefore, when ensuring that the piston rod 108 diameter D is within the gb1800-79 js5 tolerance range, controlling the piston rod H stroke can ensure that the single channel pipette pipetting liquid volume is within the standard range, therefore, electronic height measuring mechanism can be made to control the piston rod H stroke; When the piston rod stroke H is within ±0.05 tolerance, it can be ensured that the single channel pipette pipetting liquid volume is within the standard range;

[0042] Step five: based on the electronic height measuring mechanism, make multi-dimensional calibration mechanical hand 300, which is connected to the computer for control, to automatically grab, measure and calibrate the single channel pipette mass production, so as to realize high consistency in single channel pipette mass production, and make the single channel pipette batch products within the standard range, so as to solve the problem of high cost and low efficiency of mass production calibration equipment.

[0043] The single-channel pipette comprises a shell, a piston rod pressing head 100, a scale wheel knob 101, an upper push rod limiting screw 102, a stop block 103, a lower push rod limiting block 104, a piston rod push rod 105, a piston rod return spring 106, a piston rod sealing ring 107, a piston rod 108, a piston cylinder 109 and a suction head 110. The bottom end of the shell is provided with the piston cylinder 109, the piston rod 108 is sealed in the piston cylinder 109 through the piston rod sealing ring 107, so that when the piston rod 108 moves, negative pressure or positive pressure is formed in the piston cylinder 109. The bottom end of the piston cylinder 109 is provided with the suction head 110, so as to suck or squeeze liquid through the suction head 110. The top of the piston rod 108 is provided with the piston rod return spring 106, and the piston rod return spring 106 is located on the middle part of the shell, so that the top of the piston rod 108 and the bottom of the piston rod push rod 105 are in contact at all times. The piston rod push rod 105 is provided with the stop block 103, and is slidingly connected to the top end of the shell, so as to be pushed upward by the piston rod return spring 106, and stop moving when the stop block 103 hits the upper push rod limiting screw 102. The piston rod push rod 105 passes through the upper push rod limiting screw 102 and the lower push rod limiting block 104 and is fixed to the piston rod pressing head 100, and the upper push rod limiting screw 102 and the lower push rod limiting block 104 are arranged on the top end of the shell. The piston rod pressing head 100 is slidingly connected to the top end of the shell. The distance from the stop block 103 to the lower push rod limiting block 104 is the piston rod stroke H. The top end of the shell is rotationally connected with the scale wheel knob 101, and the inner cavity of the scale wheel knob 101 is slidingly connected with the piston rod pressing head 100.

[0044] Wherein: single channel pipette before use, the block 103 against the push rod upper limit lead screw 102 lower end surface; single channel pipette in use, palm hold the shell, the thumb press piston rod press head 100, so that the block 103 moves to the push rod lower limit block 104, the displacement of the interval is recorded as the piston rod stroke H, and the piston rod 108 exhausts the air in the piston cylinder 109; Then according to ISO8655 operation standard to move the suction head 110 into the liquid, slowly open the thumb, the block 103 moves the piston rod stroke H distance back to the push rod upper limit lead screw 102 lower end surface; So that the piston cylinder 109 forms a negative pressure and absorbs the liquid; Thus it can be seen that the liquid volume of single channel pipette is related to the piston rod 108 diameter D and the piston rod stroke H, that is: V = πD2 H / 4; The liquid volume accuracy of single channel pipette is closely related to the piston rod 108 diameter D machining accuracy and the piston rod stroke H control accuracy; The liquid volume accuracy of single channel pipette should be within the tolerance range of the scale wheel knob 101 display value; The scale wheel knob 101 display value and the push rod upper limit lead screw 102 are controlled by the scale wheel knob 101 rotation; When the scale wheel knob 101 rotates clockwise, the lower end surface of the push rod upper limit lead screw 102 moves down under the spiral rotation, so that the piston rod stroke H becomes smaller, and the scale wheel knob 101 display value becomes smaller at the same time; When the scale wheel knob 101 rotates counterclockwise, the lower end surface of the push rod upper limit lead screw 102 moves up under the spiral rotation, so that the piston rod stroke H becomes larger, and the scale wheel knob 101 display value becomes larger at the same time; Therefore, the accuracy of the piston rod stroke H control is related to the pitch P of the push rod upper limit lead screw 102, the position size L of the block 103, the height h size accuracy of the piston rod press head 100 and the assembly accuracy; Therefore, the liquid volume accuracy of single channel pipette is related to the piston rod 108 diameter D machining accuracy, the pitch P of the push rod upper limit lead screw 102, the position size L of the block 103, the height size h accuracy of the piston rod press head 100 and the assembly accuracy.

[0045] Single channel pipette is provided in electronic height measuring mechanism.

[0046] The electronic height measuring mechanism comprises an electronic height measuring instrument 200, a slide rail 201, a height measuring probe 202, a stand 203 and a pipette profiling positioning clamp 205, a single-channel pipette is arranged in the pipette profiling positioning clamp 205, the stand 203 is fixedly installed on the top left side of the pipette profiling positioning clamp 205, the slide rail 201 is fixedly installed on one side of the stand 203, the electronic height measuring instrument 200 is fixedly installed on the slide rail 201, the height measuring probe 202 is arranged on the electronic height measuring instrument 200, so that the height measuring probe 202 can contact the piston rod pressing head 100 and measure the piston rod stroke H, wherein the electronic height measuring instrument 200 is connected with a computer, so as to upload the measured piston rod stroke H to the computer; in this way, the piston rod stroke H is calibrated to be within the tolerance of ±0.05; and the volume of the liquid transferred by the single-channel pipette is ensured to be within the standard range.

[0047] One side of the electronic height measuring mechanism is provided with a multi-dimension calibration mechanical hand 300, so as to automatically grasp, measure and calibrate the single-channel pipette.

[0048] Although the present application has been described with reference to the embodiments above in the text, various improvements can be made and equivalent parts can be substituted without departing from the scope of the present application. In particular, each feature disclosed in the embodiments of the present application can be combined with any other feature in any way unless there is a structural conflict. The combinations of these features are not exhaustively described in the text only for the purpose of saving space and resources. Therefore, the present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A single channel pipette calibration method, characterized by, The specific steps include: Step one: accurately calculate the precision of the pipette, and based on this, determine the diameter D of the piston rod (108), the pitch P of the upper limit position screw (102) of the push rod, the position size L of the stop block (103), and the height h size of the piston rod pressing head (100) to ensure that the weighing calibration is consistent within the precision standard range; Step two: according to the precision standard of the parts processed in step one, control the diameter D of the piston rod (108), the pitch P of the upper limit position screw (102) of the push rod, the position size L of the stop block (103), and the height h size of the piston rod pressing head (100) to ensure that the parts have high interchangeability and assembly consistency, and thus ensure that the weighing calibration is consistent; Step three: make the standard production tooling fixture, control the assembly of the parts to have high consistency, and thus ensure that the weighing calibration has high consistency; Step four: since the volume of the liquid transferred by the single-channel pipette is related to the diameter D of the piston rod (108) and the piston rod stroke H, i.e. V=πD²H / 4, therefore, when the diameter D of the piston rod (108) is within the gb1800-79 js5 tolerance range, controlling the piston rod H stroke can ensure that the volume of the liquid transferred by the single-channel pipette is within the standard range, thus an electronic height measuring mechanism can be made to control the piston rod H stroke; when the piston rod stroke H is within ±0.05 tolerance, it can be ensured that the volume of the liquid transferred by the single-channel pipette is within the standard range; Step five: based on the electronic height measuring mechanism, make a multi-dimensional calibration mechanical hand (300), which is connected and controlled by a computer to automatically grab, measure and calibrate a large number of single-channel pipette products, so as to ensure high consistency in mass production of single-channel pipettes and make the single-channel pipette products within the standard range, thereby solving the problem of high cost and low efficiency of calibration equipment in mass production; The single-channel pipette comprises a shell, a piston rod pressing head (100), a scale wheel knob (101), an upper limit position screw (102) of the push rod, a stop block (103), a lower limit block (104) of the push rod, a piston rod (105), a piston rod return spring (106), a piston rod sealing ring (107), a piston rod (108), a piston cylinder (109), and a suction head (110). The bottom end of the shell is provided with a piston cylinder (109), the piston rod (108) is sealed in the piston cylinder (109) through the piston rod sealing ring (107), so that when the piston rod (108) moves, negative pressure or positive pressure is formed in the piston cylinder (109); the bottom end of the piston cylinder (109) is provided with a suction head (110) to suck or squeeze out the liquid through the suction head (110); The top of the piston rod (108) is provided with a piston rod return spring (106), and the piston rod return spring (106) is located on the middle part of the shell, so that the top of the piston rod (108) is always in contact with the bottom of the piston rod push rod (105). The piston rod push rod (105) is provided with a stop block (103), and the piston rod push rod (105) is slidingly connected to the top end of the shell, so that the piston rod push rod (105) is pushed upward under the action of the piston rod return spring (106) and stops moving when the stop block (103) hits the push rod upper limiting lead screw (102). The piston rod push rod (105) passes through the push rod upper limiting lead screw (102) and the push rod lower limiting block (104) and is fixed on the piston rod pressing head (100), and the push rod upper limiting lead screw (102) and the push rod lower limiting block (104) are arranged on the top end of the shell, the piston rod pressing head (100) is slidingly connected to the top end of the shell, the distance from the stop block (103) to the push rod lower limiting block (104) is the piston rod stroke H, and the top end of the shell is rotationally connected with the scale wheel knob (101), and the inner cavity of the scale wheel knob (101) is slidingly connected with the piston rod pressing head (100).

2. The single-channel pipette calibration method of claim 1, wherein, The single-channel pipette is arranged in the electronic height measuring mechanism; The electronic height measuring mechanism comprises an electronic height measuring instrument (200), a slide rail (201), a height measuring probe (202), a column (203) and a pipette profiling positioning clamp (205), the pipette profiling positioning clamp (205) is provided with a single-channel pipette, and the top left side of the pipette profiling positioning clamp (205) is fixedly provided with the column (203).

3. A single channel pipette calibration method according to claim 2, wherein, One side of the column (203) is fixedly provided with the slide rail (201), the electronic height measuring instrument (200) is fixedly installed on the slide rail (201), the electronic height measuring instrument (200) is provided with the height measuring probe (202), so that the height measuring probe (202) can contact the piston rod pressing head (100) and measure the piston rod stroke H.

4. The single-channel pipette calibration method of claim 3, wherein, One side of the electronic height measuring mechanism is provided with a multi-dimensional calibration mechanical hand (300), so that the single-channel pipette can be automatically grabbed, measured and calibrated. One side of the electronic height measuring mechanism is provided with a multi-dimensional calibration mechanical hand (300), so that the single-channel pipette can be automatically grabbed, measured and calibrated.

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