Pipette convenient for pipetting from volumetric flask

Abstract

The utility model belongs to the technical field of chemical analysis appliances, and particularly relates to a pipette convenient for pipetting in a volumetric flask, which comprises an upper pipette, a lower pipette and a connecting taper pipe, the upper end of the connecting taper pipe is in threaded connection with the lower end of the upper pipette, the upper pipette is provided with a positioning structure, the lower end part of the connecting taper pipe is integrally connected with a straight pipe section, and the straight pipe section is provided with a positioning structure. At least one annular groove for mounting an elastic sealing ring is formed in the straight pipe section, a positioning ring for positioning the insertion depth of the lower pipette is arranged on the straight pipe section above the annular groove, an air hole is formed in the pipe wall, close to the lower end, of the lower pipette, and a tubular jacket is detachably and hermetically connected to the position, corresponding to the air hole, of the outer wall of the lower pipette; the lower pipette is provided with an air hole, a ventilation gap communicated with the air hole is reserved between the inner wall of the tubular jacket and the outer wall of the lower pipette, and an air inlet pipe is arranged on the tubular jacket. The pipette is simple and convenient to operate, can be matched with a pipette, is convenient for taking liquid from a volumetric flask, and can be suitable for pipetting viscous liquid.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical analysis instruments, and in particular relates to a pipette which is convenient for transferring liquid from a volumetric flask. Background Art

[0002] A pipette is a type of pipette, which is used in conjunction with a pipette tip to draw liquid from a reagent bottle. It is often used to transfer small or trace amounts of liquid in a laboratory. Existing pipette tips are generally short in length and thick in diameter, and cannot be directly inserted into a volumetric flask for aspiration. Existing detachable pipettes generally do not use a tip structure compatible with the pipette, and the connection structure between the upper pipette and the lower pipette is relatively complex and often cannot achieve effective sealing. The connection operation is complicated, and an upper pipette of one specification can only be connected to a lower pipette of a single diameter, resulting in a waste of resources and an increase in the cost of experiments or analytical verification.

[0003] In addition, when the existing pipette tip is used to pipette relatively viscous liquids, when taking or releasing liquids, the viscous liquid at the lower end of the pipette nozzle of the pipette tip cannot be quickly separated from the pipette nozzle of the pipette tip, which affects the efficiency and accuracy of taking liquids. Summary of the invention

[0004] In view of the above problems, the purpose of the utility model is to provide a pipette with a simple structure, easy operation, adaptability to a pipette gun, convenience for taking liquid from a volumetric flask, and applicable to pipetting relatively viscous liquids.

[0005] The purpose of the utility model is achieved through the following technical solutions: a pipette for transferring liquid from a volumetric flask, comprising a lower pipette, a connecting cone tube and an upper pipette adapted to a pipette gun, wherein the upper end of the connecting cone tube is threadedly connected to the lower end of the upper pipette, and the upper pipette is provided with a positioning structure for positioning the connection position between the connecting cone tube and the upper pipette, the lower end of the connecting cone tube is integrally connected with a straight pipe section, at least one annular groove for installing a sealing ring is provided in the straight pipe section, an elastic sealing ring matching the diameter of the lower pipette is provided in the annular groove, and the straight pipe section is provided with a plurality of sealing rings. A positioning ring for positioning the insertion depth of the lower pipette is provided on the section above the annular groove, and the lower pipette is inserted in the straight tube section through an elastic sealing ring. An air hole is provided on the tube wall near the lower end of the lower pipette, and a tubular jacket is provided on the outer wall of the lower pipette corresponding to the position of the air hole, the upper and lower ends of the tubular jacket are detachably sealed with the outer wall of the lower pipette, and a ventilation gap is left between the inner wall of the tubular jacket and the outer wall of the lower pipette, the ventilation gap is connected with the air hole, and an air inlet pipe is provided on the tubular jacket, and the air inlet end of the air inlet pipe is connected to a high-pressure air source.

[0006] Furthermore, the positioning structure may be a positioning block or a positioning mark.

[0007] Furthermore, the lower end of the lower pipette is integrally connected with a straight tube portion, the tubular jacket comprises a jacket body, the upper end of the jacket body is integrally connected with a tapered tube, and the small end of the tapered tube is sealingly sleeved on the outer wall of the straight tube portion of the lower pipette.

[0008] Furthermore, the small end portion of the tapered tube is integrally connected with a reinforcing ring which is threadedly connected to the straight tube portion.

[0009] Furthermore, there are multiple air holes, and the multiple air holes are evenly arranged horizontally and circumferentially on the tube wall of the lower pipette.

[0010] Furthermore, the air hole is a strip-shaped air hole and the lower side of the air hole is no more than 1 mm away from the lower end of the lower pipette.

[0011] Furthermore, 2-3 annular grooves are provided in the straight pipe section from top to bottom, the positioning ring is provided at the upper end of the straight pipe section and an elastic cushion layer is provided at the bottom of the positioning ring.

[0012] Furthermore, a collar is threadedly connected to the outer wall of the lower pipette, and a limiting ring hook is provided on the collar for clamping the air inlet pipe.

[0013] Furthermore, a strip groove capable of accommodating the embedding of the air inlet pipe is provided on the outer wall of the lower pipette along the length direction of the pipe body.

[0014] Furthermore, the high-pressure air source is an ear cleaning ball, and the air inlet end of the air inlet pipe is in a trumpet shape for easy connection with the ear cleaning ball.

[0015] When the utility model is used, when the amount of liquid to be moved is small and does not exceed the capacity of the lower pipette, the lower pipette and the upper pipette adapted to the pipette gun are directly connected through the connecting cone tube. When a larger volume of liquid needs to be moved, since the upper pipette is provided with a positioning structure for positioning the connection position of the connecting cone tube and the upper pipette, and the straight tube section is provided with a positioning ring above the annular groove for positioning the insertion depth of the lower pipette, the capacity of the lower pipette, the connecting cone tube and the upper pipette after connection can be accurately controlled by the marking and the positioning ring, so that the capacity is significantly increased compared with the capacity of the lower pipette, and the same upper pipette can also be connected through The connecting spinal tubes with different diameters of the straight tube section connected thereto are replaced to connect with lower pipettes of different capacities and diameters to meet the needs of taking liquids of different capacities. The lower pipette is directly plugged into the straight tube section through an elastic sealing ring, and the connection is quick and convenient. The elastic sealing ring can seal and embrace the lower pipette. When pipetting relatively viscous liquids, the tubular jacket is installed on the outer wall of the lower pipette at a position corresponding to the air hole. When taking or releasing liquid, a high-pressure gas source blows air into the ventilation gap through the air inlet pipe, and the high-pressure gas blows off the liquid stuck in the liquid suction port at the lower end of the lower pipette through the air hole connected to the ventilation gap.

[0016] Beneficial effects: The utility model has a simple structure, is easy to operate, can be matched with a pipette gun, is convenient for taking liquid from a volumetric flask, and is suitable for pipetting relatively viscous liquids. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is described in more detail below by way of example with reference to the accompanying drawings, in which:

[0018] Figure 1 : A schematic diagram of the structure of a pipette tip in the prior art of the utility model.

[0019] Figure 2 : Schematic diagram of the structure of embodiment 1 of the present utility model.

[0020] Figure 3 : Schematic diagram of the connection structure of the conical tube, the lower pipette and the upper pipette in Example 1 of the utility model.

[0021] Figure 4 : Schematic diagram of the connection structure between the tubular jacket and the lower pipette in Example 1 of the utility model.

[0022] Figure 5 : Schematic diagram of the connection structure between the collar and the lower pipette in Example 2 of the present utility model.

[0023] In the figure: 01. straight tube part, 02. strip groove, 1. lower pipette, 2. connecting cone tube, 3. upper pipette, 4. positioning mark, 5. straight tube section, 6. annular groove, 7. elastic sealing ring, 8. positioning ring, 9. air hole, 10. tubular jacket, 11. ventilation gap, 12. air inlet pipe, 13. collar, 101. jacket body, 102. cone tube, 121. air inlet end, 81. elastic cushion layer. DETAILED DESCRIPTION

[0024] In the present utility model, for the convenience of description, the relative position relationship of each component is described according to the layout of the drawings in the specification, such as: the position relationship of up, down, left, right, etc. is determined according to the layout direction in the drawings in the specification.

[0025] Example 1, reference Figure 1 , Figure 2 , Figure 3 , Figure 4, a pipette for convenient pipetting from a volumetric flask, comprising a lower pipette 1, a connecting cone tube 2 and an upper pipette 3 adapted to a pipette gun, the upper end of the connecting cone tube 2 and the lower end of the upper pipette 3 are integrally connected with a transition straight tube for easy connection, the connecting cone tube 2 is threadedly connected to the lower end of the upper pipette 3 through the transition straight tube at the upper end, the upper pipette 3 is provided with a positioning mark 4 for locating the connection position of the connecting cone tube 2 and the upper pipette 3, the lower end of the connecting cone tube 2 is integrally connected with a straight tube section 5, at least one annular groove 6 for installing a sealing ring is provided in the straight tube section 5, and an elastic sealing ring 7 matching the diameter of the lower pipette 1 is provided in the annular groove 6. A positioning ring 8 for positioning the insertion depth of the lower pipette 1 is provided on the straight pipe section 5 above the annular groove 6. The lower pipette 1 is inserted into the straight pipe section 5 through an elastic sealing ring 7. An air hole 9 is provided on the tube wall near the lower end of the lower pipette 1, and a tubular jacket 10 is provided on the outer wall of the lower pipette 1 corresponding to the position of the air hole 9. The upper and lower ends of the tubular jacket 10 are detachably sealed and connected to the outer wall of the lower pipette 1, and a ventilation gap 11 is left between the inner wall of the tubular jacket 10 and the outer wall of the lower pipette 1. The ventilation gap 11 is connected to the air hole 9. An air inlet pipe 12 is provided on the tubular jacket 10, and the air inlet end 121 of the air inlet pipe 12 is connected to a high-pressure air source.

[0026] The lower end of the lower pipette 1 is integrally connected with a straight tube portion 01, the tubular jacket 10 includes a jacket body 101, the upper end of the jacket body 101 is integrally connected with a tapered tube 102, and the small end of the tapered tube 102 is threadedly connected to the straight tube portion 01 through an integrally connected reinforcement ring.

[0027] There are multiple air holes 9 , and the multiple air holes 9 are evenly arranged horizontally and circumferentially on the tube wall of the lower pipette 1 . The air holes 9 are strip-shaped air holes, and the lower side of the air holes 9 is no more than 1 mm away from the lower end of the lower pipette 1 .

[0028] The straight pipe section 5 is provided with 2-3 annular grooves 6 in a gap from top to bottom. The positioning ring 8 is provided at the upper end of the straight pipe section 5 and an elastic cushion layer 81 is provided at the bottom of the positioning ring 8 .

[0029] The outer wall of the lower pipette 1 is provided with a strip groove 02 along the length direction of the tube body for accommodating the air inlet pipe 12 to be embedded.

[0030] When the utility model is used, when the amount of liquid to be moved is small and does not exceed the capacity of the lower pipette 1, the lower pipette 1 and the upper pipette 3 adapted to the pipette gun are directly connected through the connecting cone 2. When a larger volume of liquid needs to be moved, since the upper pipette 3 is provided with a positioning mark 4 for locating the connection position of the connecting cone 2 and the upper pipette 1, and the straight tube section 5 is provided with a positioning ring 8 for locating the insertion depth of the lower pipette 1 above the annular groove 6, the capacity of the lower pipette 1, the connecting cone 2 and the upper pipette 3 after connection can be accurately controlled by the positioning mark 4 and the positioning ring 8, so that the capacity is significantly increased compared with the capacity of the lower pipette 1, and the same upper pipette 3 can also be connected through By replacing the connecting spinal tube 2 with different diameters of the straight tube section 5 connected thereto, it can be connected to the lower pipette 1 of different capacity and diameter to meet the needs of taking liquids of different capacities. The lower pipette 1 is directly plugged into the straight tube section 5 through an elastic sealing ring, and the connection is quick and convenient. The elastic sealing ring 7 can seal and embrace the lower pipette 1. When pipetting relatively viscous liquids, the tubular jacket 10 is installed on the outer wall of the lower pipette 1 at a position corresponding to the air hole 9. When taking or releasing liquid, the high-pressure gas source blows air into the ventilation gap 11 through the air inlet pipe 12, and the high-pressure gas blows off the liquid stuck in the liquid suction port at the lower end of the lower pipette 1 through the air hole 9 communicated with the ventilation gap 11.

[0031] Example 2, reference Figure 5 The difference from Example 1 is that a ring 13 is threadedly connected to the outer wall of the lower pipette 1, and the ring 13 is provided with a limiting ring hook that can clamp the air inlet pipe 12. When pipetting a non-viscous solution, the ring 13 and the tubular jacket 10 can be removed from the outer wall of the lower pipette 1.

[0032] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A pipette for transferring liquid from a volumetric flask, characterized in that: The invention comprises a lower pipette, a connecting cone tube and an upper pipette matched with the pipette gun, the upper end of the connecting cone tube is threadedly connected to the lower end of the upper pipette, the upper pipette is provided with a positioning structure for positioning the connection position of the connecting cone tube and the upper pipette, the lower end of the connecting cone tube is integrally connected with a straight pipe section, at least one annular groove for installing a sealing ring is arranged in the straight pipe section, an elastic sealing ring matching the diameter of the lower pipette is arranged in the annular groove, a positioning ring for positioning the insertion depth of the lower pipette is arranged on the straight pipe section above the annular groove, and the lower pipette is passed through the annular groove. An elastic sealing ring is inserted in the straight tube section, and an air hole is provided on the tube wall near the lower end of the lower pipette, and a tubular jacket is provided on the outer wall of the lower pipette corresponding to the position of the air hole, the upper and lower ends of the tubular jacket are detachably and sealedly connected to the outer wall of the lower pipette, and a ventilation gap is left between the inner wall of the tubular jacket and the outer wall of the lower pipette, and the ventilation gap is connected with the air hole, and an air inlet pipe is provided on the tubular jacket, and the air inlet end of the air inlet pipe is connected to a high-pressure air source, and there are multiple air holes, and the multiple air holes are horizontally and circumferentially evenly arranged on the tube wall of the lower pipette.

2. A pipette for convenient transfer of liquid from a volumetric flask as claimed in claim 1, characterized in that: The lower end of the lower pipette is integrally connected with a straight tube portion, the tubular jacket comprises a jacket body, the upper end of the jacket body is integrally connected with a tapered tube, and the small end of the tapered tube is sealingly sleeved on the outer wall of the straight tube portion of the lower pipette.

3. A pipette for convenient transfer of liquid from a volumetric flask as claimed in claim 2, characterized in that: The small end of the tapered tube is integrally connected with a reinforcing ring which is threadedly connected with the straight tube portion.

4. A pipette for convenient transfer of liquid from a volumetric flask as claimed in claim 1, characterized in that: The air hole is a strip-shaped air hole and the lower side of the air hole is no more than 1 mm away from the lower end of the lower pipette.

5. A pipette for convenient transfer of liquid from a volumetric flask as claimed in claim 1, characterized in that: The straight pipe section is provided with 2-3 annular grooves from top to bottom, the positioning ring is provided at the upper end of the straight pipe section and an elastic cushion layer is provided at the bottom of the positioning ring.

6. A pipette for transferring liquid from a volumetric flask as claimed in claim 1, characterized in that: A collar is threadedly connected to the outer wall of the lower pipette, and a limiting ring hook for clamping the air inlet pipe is provided on the collar.

7. A pipette for transferring liquid from a volumetric flask as claimed in claim 1, characterized in that: A strip groove capable of accommodating the insertion of the air inlet pipe is arranged on the outer wall of the lower pipette along the length direction of the pipe body.

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