Pipettor capable of adjusting gas density and gas adjusting method

Abstract

The invention aims to provide the pipettor capable of adjusting the gas density, which is simple in structure, applicable to different suction heads and capable of realizing a density adjusting function without a tool. The pipettor comprises a pipettor shell, a push-out module, a measuring range module and a density adjusting module, the measuring range module is arranged in the middle of the inner side of the pipettor shell and matched with a liquid taking head at the lower end of the pipettor shell through the push-out module, and the limiting end of the density adjusting module is matched with the rotating end of the measuring range module; the gas adjusting method comprises the following steps: S1, if the limiting clamping ring is not pressed, only the pipette has a normal measuring range adjusting function; s2, a gear is driven to rotate, and the liquid suction amount of the liquid taking head corresponds to the number displayed by the number wheel; s3, the limiting clamping ring is pressed, and the driving gear is disengaged from the stroke driving gear; and S4, the adjusting knob is rotated, the driving gear is fixed, and the digital wheel can keep the set numbers fixed. The invention is applied to the technical field of pipettors.

Description

Technical Field

[0001] This invention relates to the technical field of pipettes, and particularly to a pipette with adjustable gas density and a gas regulation method. Background Technology

[0002] Pipettes are among the most basic, core, and frequently used tools in laboratories of life sciences, chemistry, and medicine. Their core purpose can be summarized as the precise transfer and measurement of minute amounts of liquid. Most commercially available pipettes employ an air displacement design principle. Their volume scale (capacity setting) is calibrated under standard environmental conditions (typically sea level, standard atmospheric pressure, 20°C, and 50% relative humidity). Air displacement, as the name suggests, involves pressing the pipette to create negative pressure in its internal piston section. The pipette tip connects to the end of the pipette for use; after connecting the tip, it is inserted into the solution. Releasing the button allows the solution to enter the tip under air pressure. However, there are hundreds, even thousands, of different pipette tips on the market, and the internal volume varies between manufacturers, resulting in different gas capacities within each tip. To achieve maximum measurement accuracy, pipettes need to be calibrated for different tips. Actual usage environments are highly variable, especially at high altitudes where air pressure is lower and air is thinner. Under the same piston stroke, the absolute value of the negative pressure formed inside the pipette tip decreases, resulting in the actual volume of liquid drawn being less than the set value. In these variable environments, there is an urgent need for a method that can quickly and accurately compensate for gas density. Furthermore, users often use different types of pipette tips, such as extended tips for deeper containers. It is impractical for customers to calibrate their pipettes with different tips every time. Therefore, a pipette with gas density adjustment functionality is needed to meet user needs. For example, when using tip A, the density adjustment scale could be set to 0; when using tip B, the scale could be set to 1. This allows customers to use different density adjustment scales for different tips. Rotating the density adjustment scale changes the volume of liquid drawn by the pipette. If a simple pipette with adjustable gas density and a gas adjustment method could be designed that is compatible with different tips and requires no tools, the above problems could be solved. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and to provide a pipette with adjustable gas density that is simple in structure, applicable to different pipette tips, and can achieve density adjustment function without tools, as well as a gas adjustment method.

[0004] The technical solution adopted in this invention is as follows: This invention includes a pipette housing, an ejection module, a volumetric module, and a density adjustment module. The volumetric module is disposed in the middle of the inner side of the pipette housing and cooperates with the liquid-taking head at the lower end of the pipette housing through the ejection module. The limiting end of the density adjustment module cooperates with the rotating end of the volumetric module.

[0005] Furthermore, the measuring range module includes an adjustment knob, a drive frame, a stroke drive gear, a drive gear, a speed-changing wheel, and a digital wheel. The adjustment knob is located at the upper end of the pipette housing. The stroke drive gear is connected to the adjustment knob through the drive frame. The drive gear rotates in conjunction with the stroke drive gear. The drive gear rotates in conjunction with the digital wheel through the speed-changing wheel.

[0006] Furthermore, the stroke drive gear is floatingly connected to the drive frame via a drive spring, and the drive spring drives the stroke drive gear to engage with the drive gear.

[0007] Furthermore, the ejection module includes a pressing rod, a screw, a piston rod, a piston cylinder, and a sealing ring. The adjustment knob is connected to the piston rod via the pressing rod. The screw engages with a nut structure on the fixed end in the middle of the pipette housing and rotates with the digital wheel. The boss structure in the middle of the pressing rod engages with the screw for limiting. The piston cylinder is located at the lower end of the pipette housing. The sealing ring is located at the lower end of the piston cylinder. The piston rod engages with the upper end of the piston cylinder.

[0008] Furthermore, the density adjustment module includes a limiting retaining ring, a driving pressure plate, a density adjustment scale wheel, and a limiting retaining seat. The limiting retaining ring drives the driving pressure plate to cooperate with the density adjustment scale wheel, the driving spring drives the limiting retaining ring to reset, and the limiting retaining seat cooperates with the driving frame and the stroke driving gear.

[0009] Furthermore, a piston rod spring is provided inside the piston cylinder, and the piston rod spring cooperates with the piston rod.

[0010] Furthermore, the screw engages with the stroke drive gear via a hexagonal slider.

[0011] Furthermore, the digital wheel includes a main digital wheel and several secondary digital wheels.

[0012] The gas conditioning method includes the following steps; S1. When the limit ring is not pressed, the drive plate is disengaged from the density adjustment scale wheel, and the drive gear is engaged with the stroke drive gear. At this time, turning the adjustment knob will only perform the normal range adjustment function of the pipette. S2. When the drive gear rotates, the digital wheel displaying the range rotates along with the screw, and the liquid intake of the liquid taking head corresponds to the number displayed on the digital wheel; S3. When the limiting ring is pressed, the driving plate meshes with the density adjustment scale wheel, the driving gear disengages from the stroke driving gear, and the driving gear loses power due to the disengagement of the stroke driving gear. S4. Rotate the adjustment knob, and the screw and the density adjustment scale wheel will rotate, while the drive gear will remain stationary. Therefore, the digital wheel will also remain stationary at the set number.

[0013] The beneficial effects of this invention are as follows: Under normal circumstances, when the adjustment knob is turned, the drive gear assembly rotates together. The drive gear on the drive gear drives the gear shift wheel, which in turn drives the main digital wheel, and then drives the other three digital wheels to rotate. The main digital wheel and the other digital wheels display a 4-digit range. The stroke drive teeth inside the drive gear assembly drive the hexagonal slider to rotate. The hexagonal slider is connected to the screw, so when the hexagon rotates, it will also be affected by the screw pitch and slide. The bottom of the screw is connected to a pressing rod, which is connected to a piston rod, which is connected to a sealing ring. When the adjustment knob is turned counterclockwise, the exposed distance of the lower end of the screw decreases, the stroke of the pressing rod increases, and the liquid absorption increases. Similarly, when the adjustment knob is turned clockwise, the exposed distance of the lower end of the screw increases, the stroke of the pressing rod decreases, and the liquid absorption decreases. At this time, the liquid absorption corresponds to the range composed of 4 digits.

[0014] The density adjustment module is enhanced as follows: When the limit retaining ring is pressed a certain distance, it displaces the drive plate. The teeth on the drive plate mesh with the teeth on the density adjustment scale wheel. The density adjustment scale wheel displays numbers, which change as it rotates. Meanwhile, the drive gear and the stroke drive gear disengage. At this point, rotating the adjustment knob only drives the stroke drive gear, which in turn drives the hexagonal slider. The hexagonal slider drives the screw drive to change the suction volume. The drive gear, lacking power, cannot drive the main digital wheel and the digital wheel to establish the 4-digit volume range corresponding to the suction range. This mechanism utilizes the change in the density adjustment wheel's numerical value to correspond to the screw rotation, thereby eliminating errors caused by differences in suction tips from different brands. This density adjustment feature eliminates the accuracy issues caused by differences in density between different brands of pipette tips. It also solves the problem of users needing to use pipettes in different environments (such as in cell culture incubators (rich in CO2), anaerobic workstations, or when using specific protective gases (such as nitrogen or argon), where the density of the working gas differs greatly from that of air). The feature allows users to return to the 0 point. For example, if the density adjustment scale is 0 in a normal environment, it needs to be adjusted to 1 to obtain maximum accuracy when using a pipette in a CO2 environment. After using the pipette in a CO2 environment, the scale can be adjusted back to 0 for use in a normal environment. Attached Figure Description

[0015] Figure 1 This is a perspective view of the present invention; Figure 2 This is a perspective view of the hidden part of the structure of the present invention; Figure 3 This is a plan view of the hidden part of the structure of the present invention; Figure 4 This is a plan view of another state of the hidden part of the structure of the present invention. Detailed Implementation

[0016] like Figures 1 to 4 As shown, in this embodiment, the present invention includes a pipette housing 1, an ejection module 2, a volumetric module 3, and a density adjustment module 4. The volumetric module 3 is located in the middle of the inner side of the pipette housing 1 and cooperates with the dispensing head 5 at the lower end of the pipette housing 1 through the ejection module 2. The limiting end of the density adjustment module 4 cooperates with the rotating end of the volumetric module 3. Therefore, under normal transmission conditions, the density adjustment drive wheel does not rotate; the drive gear assembly only drives the gear shift wheel, thereby changing the digital display. When the limiting retaining ring is pressed, the drive plate moves, and the teeth on the drive plate engage with the teeth on the density adjustment scale wheel. The drive plate then drives the drive frame, disengaging the stroke drive gear from the drive gear. After the drive gear disengages from the stroke drive gear, it loses power. When the adjustment knob is rotated, only the density adjustment scale wheel changes its value under the drive of the drive plate, thus realizing the pipette density adjustment function.

[0017] like Figures 2 to 4 As shown, in this embodiment, the range module 3 includes an adjustment knob 31, a drive frame 32, a stroke drive gear 33, a drive gear 34, a speed change wheel 35, and a digital wheel 36. The adjustment knob 31 is disposed on the upper end of the pipette housing 1. The stroke drive gear 33 is connected to the adjustment knob 31 through the drive frame 32. The drive gear 34 is rotatably engaged with the stroke drive gear 33. The drive gear 34 is rotatably engaged with the digital wheel 36 through the speed change wheel 35. Therefore, when the adjustment knob 31 is rotated, it drives the drive frame 32, which in turn drives the stroke drive gear 33 and the drive gear 34; when pressed, it drives the pressing rod 21, which in turn drives the piston rod 23. The piston rod 23, the sealing ring 25, and the piston cylinder 24 form a piston structure. When the adjustment knob 31 is pressed, it generates negative pressure. After the liquid taking head 5 is placed into the solution and the adjustment knob 31 is released, the piston rod 23 will return to its original position under the action of the piston rod spring 26, thereby drawing the solution into the liquid taking head 5.

[0018] like Figures 2 to 4As shown, in this embodiment, the stroke drive gear 33 is floatingly connected to the drive frame 32 via a drive spring 37, and the drive spring 37 drives the stroke drive gear 33 to engage with the drive gear 34. Therefore, the stroke drive gear 33 and the drive gear 34 mesh together through a toothed structure, and the drive spring 37 drives the stroke drive gear 33 to mesh with the drive gear 34.

[0019] like Figures 2 to 4 As shown, in this embodiment, the ejection module 2 includes a pressing rod 21, a screw 22, a piston rod 23, a piston cylinder 24, and a sealing ring 25. The adjusting knob 31 is connected to the piston rod 23 via the pressing rod 21. The screw 22 engages with a nut structure on the fixed end of the pipette housing 1 and rotates with the digital wheel 36. The boss structure in the middle of the pressing rod 21 is limited by the screw 22. The piston cylinder 24 is located at the lower end of the pipette housing 1, the sealing ring 25 is located at the lower end of the piston cylinder 24, and the piston rod 23 engages with the upper end of the piston cylinder 24. Therefore, the upper end of the pressing rod 21 is connected to the adjusting knob 31, the middle boss is limited by the screw 22, and the lower end is connected to the piston rod 23. When the piston rod 23 is pressed by the pressing rod 31, the metal part at the lower end of the piston rod 23 slides within the sealing ring 25, forming a piston structure together with the piston cylinder 24.

[0020] like Figures 2 to 4 As shown, in this embodiment, the density adjustment module 4 includes a limiting retaining ring 41, a driving pressure plate 42, a density adjustment scale wheel 43, and a limiting retaining seat 44. The limiting retaining ring 41 drives the driving pressure plate 42 to cooperate with the density adjustment scale wheel 43. The driving spring 37 drives the limiting retaining ring 41 to reset. The limiting retaining seat 44 cooperates with the driving frame 32 and the stroke driving gear 33. Therefore, when the limiting retaining ring 41 is pressed, it can move the driving pressure plate 42. The driving pressure plate 42 has a toothed structure. When the pressing is released, the driving spring 37 will drive the driving pressure plate 42, which will drive the limiting retaining ring 41 to reset. When the limiting retaining ring 41 is pressed, it will move, thereby driving the driving pressure plate 42 to mesh with the gear on the density adjustment scale wheel 43.

[0021] like Figures 2 to 4 As shown, in this embodiment, a piston rod spring 26 is provided inside the piston cylinder 24, and the piston rod spring 26 cooperates with the piston rod 23. Therefore, the piston rod spring 26 provides a restoring force to the piston rod 23.

[0022] like Figures 2 to 4As shown, in this embodiment, the screw 22 engages with the stroke drive gear 33 via a hexagonal slider 27. Thus, the hexagonal slider 27 is connected to the screw 22, rotates with the stroke drive gear 33, but also slides within the stroke drive gear 33 under the action of the screw pitch.

[0023] like Figure 3 and Figure 4 As shown, in this embodiment, the digital wheel 36 includes a main digital wheel and several auxiliary digital wheels. Thus, the main digital wheel carries numbers and is driven by the gear shift wheel 35, while the several auxiliary digital wheels also carry numbers, and together, driven by the main digital wheel, form a range display.

[0024] The working principle of this invention is as follows: S1. When the limiting ring 41 is not pressed, the driving plate 42 disengages from the density adjustment scale wheel 43, and the driving gear 34 meshes with the stroke driving gear 33. At this time, rotating the adjustment knob 31 will only perform the normal range adjustment function of the pipette; S2. When the driving gear 34 rotates, the range display digital wheel 36 and the screw 22 rotate, and the liquid aspiration volume of the liquid dispensing head 5 corresponds to the number displayed on the digital wheel 36; S3. When the limiting ring 41 is pressed, the driving plate 42 meshes with the density adjustment scale wheel 43, and the driving gear 34 disengages from the stroke driving gear 33. The driving gear 34 loses power due to the disengagement of the stroke driving gear 33; S4. When the adjustment knob 31 is rotated, the screw 22 and the density adjustment scale wheel 43 rotate, while the driving gear 34 remains stationary. Therefore, the digital wheel 36 will also remain stationary at the set number.

[0025] For example, if a pipette is set to a suction volume of 1000 μL, and the user uses the A pipette tip provided by the manufacturer to aspirate liquid and measures it on a balance, the balance should also show a converted suction volume of 1000 μL. However, if the user wants to use the B pipette tip, because the B pipette tip is from a different manufacturer or is designed differently from the A pipette tip, the actual suction volume set to 1000 μL will only be 999 μL. This is where the density adjustment function comes in handy. Because the engagement between the drive gear and the stroke drive is disengaged, turning the adjustment knob does not rotate the digital wheel, which still displays 1000. However, the density adjustment scale wheel and screw can rotate, increasing the aspirated volume, which is equivalent to error compensation. At this time, the digital display on the density adjustment scale wheel changes from 0 to 1, and the aspirated value changes from 999μL to 1000μL. When the user wants to switch back to tip A, they only need to turn the density adjustment scale wheel back to 0 (the same principle applies to different environments). The density adjustment function ensures maximum aspirated accuracy when switching between different tips, eliminating the need to calibrate the pipette when changing tips.

[0026] Although the embodiments of the present invention are described with reference to actual solutions, they do not constitute a limitation on the meaning of the present invention. Modifications to the embodiments and combinations with other solutions based on this specification will be obvious to those skilled in the art.

Claims

1. A pipette with adjustable gas density, comprising a pipette housing (1), an ejection module (2), a volumetric module (3), and a density adjustment module (4), characterized in that: The volumetric module (3) is located in the middle of the inner side of the pipette housing (1) and cooperates with the liquid-taking head (5) at the lower end of the pipette housing (1) through the push-out module (2). The limiting end of the density adjustment module (4) cooperates with the rotating end of the volumetric module (3).

2. The adjustable gas density pipette according to claim 1, characterized in that: The range module (3) includes an adjustment knob (31), a drive frame (32), a stroke drive gear (33), a drive gear (34), a speed change wheel (35), and a digital wheel (36). The adjustment knob (31) is located at the upper end of the pipette housing (1). The stroke drive gear (33) is connected to the adjustment knob (31) through the drive frame (32). The drive gear (34) rotates with the stroke drive gear (33). The drive gear (34) rotates with the digital wheel (36) through the speed change wheel (35).

3. A pipette with adjustable gas density according to claim 2, characterized in that: The stroke drive gear (33) is floatingly connected to the drive frame (32) via a drive spring (37), and the drive spring (37) drives the stroke drive gear (33) to cooperate with the drive gear (34).

4. A pipette with adjustable gas density according to claim 3, characterized in that: The ejection module (2) includes a pressing rod (21), a screw (22), a piston rod (23), a piston cylinder (24), and a sealing ring (25). The adjustment knob (31) is connected to the piston rod (23) through the pressing rod (21). The screw (22) is engaged with the nut structure on the fixed end of the middle part of the pipette housing (1) and rotates with the digital wheel (36). The boss structure in the middle part of the pressing rod (21) is engaged with the screw (22) for limiting. The piston cylinder (24) is located at the lower end of the pipette housing (1). The sealing ring (25) is located at the lower end of the piston cylinder (24). The piston rod (23) is engaged with the upper end of the piston cylinder (24).

5. A pipette with adjustable gas density according to claim 4, characterized in that: The density adjustment module (4) includes a limiting retaining ring (41), a driving pressure plate (42), a density adjustment scale wheel (43), and a limiting retaining seat (44). The limiting retaining ring (41) drives the driving pressure plate (42) to cooperate with the density adjustment scale wheel (43). The driving spring (37) drives the limiting retaining ring (41) to reset. The limiting retaining seat (44) cooperates with the driving frame (32) and the stroke driving gear (33).

6. A pipette with adjustable gas density according to claim 5, characterized in that: A piston rod spring (26) is provided inside the piston cylinder (24), and the piston rod spring (26) cooperates with the piston rod (23).

7. A pipette with adjustable gas density according to claim 6, characterized in that: the screw (22) is engaged with the stroke drive gear (33) via a hexagonal slider (27).

8. A pipette with adjustable gas density according to claim 7, characterized in that: The number wheel (36) includes a main number wheel and several sub-number wheels.

9. A gas regulation method for an adjustable gas density pipette according to claim 7, characterized in that: It includes the following steps: S1. When the limit ring (41) is not pressed, the drive plate (42) is disengaged from the density adjustment scale wheel (43), and the drive gear (34) meshes with the stroke drive gear (33). At this time, turning the adjustment knob (31) will only perform the normal range adjustment function of the pipette. S2. When the drive gear (34) rotates, the digital wheel (36) displaying the range rotates with the screw (22), and the amount of liquid absorbed by the liquid head (5) corresponds to the number displayed by the digital wheel (36); S3. When the limiting ring (41) is pressed, the driving plate (42) meshes with the density adjustment scale wheel (43), the driving gear (34) disengages from the stroke driving gear (33), and the driving gear (34) loses power due to the disengagement of the stroke driving gear (33). S4. When the adjustment knob (31) is turned, the screw (22) and the density adjustment scale wheel (43) rotate, while the drive gear (34) remains stationary. Therefore, the number wheel (36) will also remain stationary at the set number.

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