A glass measuring tube effective to prevent liquid overshoot

Abstract

The utility model provides a kind of glass measuring tube that can effectively prevent liquid overshoot, including measuring tube, vent pipe and pumping liquid pipe, measuring tube is sequentially provided with hanging liquid column bubble, measuring bubble, first buffer bubble and second buffer bubble from bottom to top, and its lower end is connected with the bottom of the liquid storage bubble of pumping liquid pipe lower end by U-shaped bend pipe, and the bottom of U-shaped bend pipe is provided with drainage pipe.The utility model is provided with multistage buffer bubble and U-shaped bend pipe communication structure on measuring tube, which can effectively slow down the liquid flow rate and form a stable liquid column, avoid the measurement error caused by liquid overshoot in traditional viscometer, and at the same time realize rapid drainage and thorough cleaning, with the advantages of reasonable structure design, effective avoidance of overshoot phenomenon, easy cleaning and maintenance and high measurement accuracy.

Description

Technical Field

[0001] This utility model relates to a viscosity measuring tube, and more particularly to a glass measuring tube that can effectively prevent liquid over-rushing. Background Technology

[0002] Ubbelohde viscometers, commonly used for measuring the kinematic viscosity of liquids, offer high accuracy but suffer from several technical drawbacks in practical applications. Their three-tube, upward-opening design necessitates sample addition and drainage from the top of the instrument, making waste discharge prone to contamination of all three tubes. Due to structural limitations, residual liquid is difficult to completely drain, increasing cleaning complexity and potentially distorting test data. Furthermore, traditional cleaning methods require extensive use of organic solvents for repeated rinsing, increasing operating costs and posing environmental risks.

[0003] Furthermore, existing viscometers, with their single-buffered design, struggle to effectively control flow rate during liquid flow, leading to overrush and directly impacting measurement accuracy. More significantly, the traditional open-structure design poses a safety hazard due to liquid splashing during operation and hinders automation, severely limiting testing efficiency. These technical shortcomings collectively restrict the application of Ubbelohde viscometers in precision measurement. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a glass measuring tube that can effectively prevent liquid over-rushing, which has the advantages of reasonable structural design, effective control of liquid flow rate, avoidance of over-rushing, easy cleaning and maintenance, and high measurement accuracy, in view of the defects of the prior art.

[0005] To solve the above-mentioned technical problems, this utility model adopts the following technical solution:

[0006] A glass measuring tube that can effectively prevent liquid overcurrent includes a measuring tube, a venting tube, and a liquid extraction tube. The measuring tube is provided with a liquid-holding bulb, a measuring bulb, a first buffer bulb, and a second buffer bulb arranged sequentially from bottom to top. Its lower end is connected to the bottom of the liquid storage bulb at the lower end of the liquid extraction tube through a U-shaped bend. A drain pipe is provided at the bottom of the U-shaped bend.

[0007] Preferably, the liquid-coated ball is positioned at the lower end of the measuring tube, and its bottom is connected to one end of the U-shaped bend.

[0008] Preferably, the liquid-coated bulb and the measuring bulb are connected by a capillary tube, and the connection point is smoothly transitioned by a tapered conical opening.

[0009] Preferably, the capillary tube and its tapered constriction at the upper and lower ends are integrally formed with the measuring tube around it, and the cross-section of the tapered constriction is an isosceles trapezoidal structure.

[0010] Preferably, the measuring bulb, the first buffer bulb, and the second buffer bulb are arranged at intervals from bottom to top at the upper end of the measuring tube, and are connected to each other through the inner cavity of the tube.

[0011] Preferably, the size of the measuring bulb, the suspended liquid column bulb, the first buffer bulb, and the second buffer bulb gradually decreases, and the first buffer bulb and the second buffer bulb are the same size.

[0012] Preferably, the venting tube is arranged parallel to the inner side of the measuring tube, and its lower end is inclined downwards and smoothly connected to the upper side of the suspended liquid column bulb.

[0013] Preferably, the liquid extraction tube is arranged parallel to the right side of the measuring tube, and its lower end is connected to the top of the liquid storage bulb.

[0014] Preferably, the measuring tube, the venting tube, and the liquid extraction tube are arranged in a triangular shape in cross-section, and the angle between the venting tube and the liquid extraction tube relative to the measuring tube is 30-90°.

[0015] Preferably, the measuring tube, venting tube, and liquid extraction tube are integrally formed and made of transparent glass.

[0016] The present invention adopts the above technical solution and has the following technical effects compared with the prior art:

[0017] This invention relates to a glass measuring tube and its components that can effectively prevent liquid over-rushing. By setting up a multi-stage buffer bulb and a U-shaped bend connecting structure on the measuring tube, the liquid flow rate is effectively slowed down and a stable liquid column is formed, avoiding the measurement error caused by liquid over-rushing in traditional viscometers. At the same time, it can achieve rapid liquid drainage and thorough cleaning. It has the advantages of reasonable structural design, effective control of liquid flow rate, avoidance of over-rushing, easy cleaning and maintenance, and high measurement accuracy. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a glass measuring tube that can effectively prevent liquid over-rushing according to the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of a viscosity measurement system using a glass measuring tube that can effectively prevent liquid over-rushing, as described in this utility model. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0021] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] In existing technologies, Ubbelohde viscometers, as gravity-type capillary viscometers, are widely used for measuring the kinematic viscosity of liquids. Traditional devices employ a three-port upward design, requiring sample addition and drainage from the top, leading to waste liquid residue contaminating the tube walls, making cleaning difficult and posing safety hazards. Furthermore, existing structures only have a single buffer bulb, making them prone to overshooting during liquid flow, affecting measurement accuracy. Manual operation is difficult to automate, and residual liquid can easily cause cross-contamination, posing operational risks, especially when handling volatile or corrosive liquids.

[0023] like Figure 1 As shown, in order to solve the above-mentioned problems in the prior art, this application proposes a glass measuring tube that can effectively prevent liquid overflow, including a measuring tube 10, a venting tube 20 and a liquid extraction tube 30. The measuring tube 10 is provided with a liquid-holding bulb 11, a measuring bulb 12, a first buffer bulb 13 and a second buffer bulb 14 arranged sequentially from bottom to top, and its lower end is connected to the bottom of the liquid storage bulb 31 at the lower end of the liquid extraction tube 30 through a U-shaped bend 15. A drain pipe 16 is provided at the bottom of the U-shaped bend 15.

[0024] The suspended liquid column bulb 11 refers to a spherical volume cavity located at the lower end of the measuring tube 10, which can be made of spherical or ellipsoidal glass and is used to stabilize the initial liquid column height and form a suspended liquid column. The measuring bulb 12 refers to a standard volume cavity located above the suspended liquid column bulb 11, which can be made of a calibrated glass bulb and is used to define the reference measurement volume of the liquid being measured. The first buffer bulb 13 and the second buffer bulb 14 refer to buffer structures distributed at intervals along the axial direction of the measuring tube, which can be made of glass bulbs with the same or decreasing diameters connected in series and are used to absorb the kinetic energy of the liquid flow step by step. The U-shaped bend 15 refers to a curved flow channel connecting the measuring tube 10 and the lower end of the liquid storage bulb 31, which can be made of a semi-circular curved glass tube and promotes complete liquid discharge through the siphon effect. The drain pipe 16 refers to the outlet channel located at the lowest point of the U-shaped bend 15, which can be made of a vertically downward extending glass capillary tube and is used to completely discharge residual liquid.

[0025] Specifically, after the liquid enters the measuring tube 10 from the storage bulb 31 through the U-shaped bend 15, the liquid column bulb 11 forms a stable liquid column reference. As the liquid flows upward, the measuring bulb 12 limits the volume of the measured liquid, which then passes through two stages of buffer bulbs, reducing the flow velocity through volume gradient changes. The vent pipe 20 maintains the pressure balance of the measuring system, and the suction and discharge pipe 30 independently completes the liquid suction and discharge operations. During the discharge stage, the liquid is completely discharged through the discharge pipe 16 at the bottom of the U-shaped bend 15 under the action of gravity, and the residual liquid is removed by the siphon effect. The double buffer bulb structure causes the kinetic energy of the liquid flow to decay in stages, avoiding oscillation of the liquid surface at the measurement endpoint.

[0026] Compared to existing technologies, traditional equipment using a single-buffered bulb structure suffers from overshoot due to the concentrated release of kinetic energy at the liquid flow end. This solution, however, utilizes a double-buffered bulb for stepped kinetic energy absorption, enabling precise and controllable liquid level stopping position. This effectively eliminates overshoot and improves the consistency of the liquid level stopping position. Furthermore, it achieves complete drainage of the liquid inside the measuring tube, avoiding cross-contamination and wasting cleaning solvent.

[0027] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the liquid-coated bulb 11 is positioned at the lower end of the measuring tube 10, with its bottom connected to one end of the U-shaped bend 15. When the liquid-coated bulb 11 is at the bottom of the measuring tube 10, the liquid naturally accumulates inside the bulb under gravity and flows directly into the U-shaped bend 15 through the bottom opening. This arrangement eliminates the need for the liquid to overcome an additional height difference during discharge, thereby reducing residue on the tube wall. The interconnected structure of the U-shaped bend 15 forms a continuous liquid flow channel, allowing the liquid to flow unidirectionally inside the bend through the combined action of gravity and surface tension, preventing backflow or stagnation.

[0028] This application further proposes that the liquid-coated bulb 11 and the measuring bulb 12 are connected by a capillary tube, and the connection point adopts a smooth transition with a tapered constriction. A capillary tube refers to a tubular structure with a small inner diameter, specifically formed from glass through hot stretching. Its narrow channel throttles the liquid flow, thereby reducing the risk of sudden velocity changes. The smooth transition with a tapered constriction refers to the linearly tapering shape of the cross-section at the connection point. Specifically, it can be formed using glass blowing technology to create an isosceles trapezoidal cross-section transition structure, eliminating turbulence and local resistance caused by right-angle connections.

[0029] Specifically, when the liquid flows from the liquid-coated bulb 11 to the measuring bulb 12, the throttling effect of the capillary limits the flow velocity within a stable range, preventing liquid overrush due to inertia. In the connected region, the tapered constriction guides the liquid flow direction through a gradual change in cross-section, maintaining streamline continuity and preventing eddies or stagnation caused by abrupt changes in cross-section. For example, the inclination angle of the tapered constriction can be 30-60 degrees, and its length can be 2-5 times the capillary diameter, achieving laminar flow maintenance through geometric optimization.

[0030] Furthermore, this application proposes that the capillary tube and its tapered constriction ends are integrally formed with the measuring tube 10 around its periphery. This integral forming process creates a seamless, smooth inner wall at the connection between the capillary tube and the bulb, eliminating the abrupt changes in flow resistance caused by seams in traditional split structures. The cross-section of the tapered constriction end is an isosceles trapezoid. This isosceles trapezoidal design allows the cross-section to gradually contract as the liquid enters the capillary tube from the bulb, resulting in uniform kinetic energy distribution; conversely, the cross-section gradually expands as the liquid enters the bulb from the capillary tube, preventing backflow.

[0031] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the measuring bulb 12, the first buffer bulb 13, and the second buffer bulb 14 are arranged at intervals from bottom to top at the upper end of the measuring tube 10, and are interconnected through the inner cavity of the tube. The interval arrangement from bottom to top means that the three bulbs are arranged sequentially from low to high in the order of measuring bulb 12, first buffer bulb 13, and second buffer bulb 14, with a certain distance maintained between adjacent bulbs. This can be achieved by blowing bulbs of different diameters in segments on the measuring tube, with the spacing length being 0.5 to 2 times the bulb diameter. This spacing provides a progressively buffering space for the liquid flow.

[0032] Specifically, when the liquid flows upward from the measuring bulb 12 under the influence of gravity, it first enters the first buffer bulb 13, where its expanded volume reduces the flow velocity and disperses kinetic energy. Subsequently, the liquid enters the second buffer bulb 14, further consuming the remaining kinetic energy. The continuous channels within the tube's internal cavity allow the liquid to smoothly enter the next stage after buffering. Through the energy dissipation effect of the two-stage buffer structure, the inertia of the liquid flow is gradually weakened, thus avoiding a sudden rise in liquid level caused by a single release of kinetic energy.

[0033] Compared to existing technologies, traditional viscometers only have a single buffer bulb, and the liquid may still overshoot due to residual kinetic energy after passing through the buffer structure. This solution adds a second buffer bulb 14 to form a multi-stage buffer system, which allows the liquid kinetic energy to decay in stages. At the same time, the coherent design of the tube cavity maintains flow stability, thereby more effectively suppressing sudden changes in flow velocity.

[0034] Through the above technical solution, this application can solve the problem of insufficient energy absorption in a single-stage buffer structure. By using the stepped kinetic energy dissipation effect of the two-stage buffer bulbs, the velocity fluctuation during liquid flow is significantly reduced, preventing the liquid level from exceeding the predetermined scale line during measurement, and ensuring the accuracy and repeatability of viscosity measurement data.

[0035] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the sizes of the measuring bulb 12, the suspended liquid column bulb 11, the first buffer bulb 13, and the second buffer bulb 14 gradually decrease, and that the first buffer bulb 13 and the second buffer bulb 14 are the same size. The gradually decreasing size means that the measuring bulb 12 has the largest volume, followed by the suspended liquid column bulb 11, and the first buffer bulb 13 and the second buffer bulb 14 have the smallest. This can be achieved by arranging spherical cavities of different diameters in sequence, creating a flow resistance gradient through volume differences. The same size for the first buffer bulb and the second buffer bulb 14 means that they have the same internal volume and geometric dimensions. This can be achieved by using a symmetrical structure formed by the same mold, maintaining continuous flow resistance through a uniform cross-section design.

[0036] Specifically, when the liquid enters the suspended liquid column bubble from the measuring bubble 12, the flow cross-sectional area decreases due to the reduced size of the bubble, initially suppressing the flow velocity. Subsequently, the liquid enters the first buffer bubble 13 and the second buffer bubble 14. The identical size of both ensures constant flow resistance, and the kinetic energy of the liquid is gradually consumed under the buffering effect of two identical conditions. This sequence of bubbles, from large to small, creates progressively increasing flow resistance, preventing turbulence caused by abrupt changes in cross-section. Simultaneously, the dual buffer structure extends the velocity stabilization path, resulting in a more uniform distribution of liquid flow velocity.

[0037] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the vent pipe 20 is arranged parallel to the inner side of the measuring pipe 10, and its lower end is inclined downwards and smoothly connected to the upper side of the suspended liquid column bulb 11. "Parallel to the inner side of the measuring pipe 10" means that the vent pipe 20 is parallel to the measuring pipe 10 and located in its inner region. Specifically, this can be achieved by having a consistent spacing between the pipe axes and extending along the axial direction of the measuring pipe. This layout makes the pipeline structure compact and facilitates the formation of a stable fluid channel. "Inclined downwards and smoothly connected to the upper side of the suspended liquid column bulb 11" means that the end of the vent pipe 20 extends downwards at an inclined angle and connects with the upper part of the side wall of the suspended liquid column bulb 11. Specifically, this can be achieved by bending the end of the pipe to form an arc-shaped transition section with an inclination angle of 30-60°. This design guides the liquid flow direction by gravity and eliminates abrupt changes in flow resistance at the connection point.

[0038] Specifically, when the vent pipe 20 is arranged parallel to the inside of the measuring pipe, the distance between its pipe walls can be controlled within the range of 5-30 mm, achieving pipe integration by reducing the external space occupied. The downward-sloping arc-shaped transition section at the lower end of the vent pipe 20 forms a continuous curved surface with the side wall of the suspended liquid column bulb 11. Under the action of gravity, the liquid flows smoothly along the pipe wall into the inner cavity of the bulb, avoiding the formation of stagnant areas at the connection. The smooth transition structure keeps the liquid in a laminar flow state, reducing liquid level fluctuations caused by sudden changes in flow velocity. During the automatic cleaning process, the cleaning fluid can flush away residues on the pipe wall along the inclined pipe and concentrate the waste liquid into the suspended liquid column bulb through the arc-shaped transition section, preventing the formation of cleaning dead zones.

[0039] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the liquid extraction / discharge pipe 30 is arranged parallel to the right side of the measuring pipe 10, and its lower end is connected to the top of the liquid storage bulb 31. The parallel arrangement of the liquid extraction / discharge pipe means that the pipe body is parallel to the measuring pipe 10 and spaced a certain distance apart. Specifically, this can be achieved by extending a glass tube coaxially and fixing it to a support frame. This arrangement allows the liquid delivery path and the measuring path to form independent channels. The connection to the top of the liquid storage bulb 31 means that the lower opening of the liquid extraction / discharge pipe is directly connected to the upper cavity of the liquid storage bulb 31. This design allows the liquid to naturally flow back to the liquid storage bulb 31 under gravity.

[0040] Specifically, the extraction / discharge pipe 30 forms an independent pipeline system arranged parallel to the right side. Liquid is extracted and discharged through this pipe under the control of external equipment, avoiding intersection with the liquid flow path inside the measuring pipe. The connection between the lower end of the extraction / discharge pipe and the top of the storage bulb 31 forms a closed loop. Under the negative pressure of the injection pump, liquid is drawn from the top of the storage bulb to the extraction / discharge pipe 30, achieving directional drainage. This structure ensures that waste liquid is discharged through a single channel, the extraction / discharge pipe 30, reducing pipe wall residue. At the same time, the connection position at the top of the storage bulb 31 ensures that the liquid completely flows back under gravity, avoiding droplet splashing caused by traditional open drainage.

[0041] Compared to existing technologies, traditional Ubbelohde viscometers share a channel between the drain port and the measuring tube, causing liquid to come into contact with the inner walls of all tubes during drainage. This solution, however, separates the drainage path through independent extraction and discharge pipes, requiring only the cleaning of a single pipe. Existing technologies rely on manual pouring for drainage, which cannot completely empty the tube and easily contaminates the operating environment. This solution, through a sealed extraction and discharge pipe combined with automated equipment, achieves controllable liquid recovery.

[0042] Through the above technical solutions, this application solves the problem of large drainage pollution area, allowing liquid to be discharged only through independent pipelines, reducing cleaning difficulty; through the closed drainage path design, liquid splashing and residue are avoided; through pipeline layout optimization, rapid docking with injection pumps or air pumps is achieved, providing a structural basis for automated operation.

[0043] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the measuring tube 10, the venting tube 20, and the liquid extraction tube 30 are arranged in a triangular pattern in cross-section, and the angle between the venting tube 20 and the liquid extraction tube 30 relative to the measuring tube 10 is 30-120°. The triangular arrangement refers to the three tubes forming a non-collinear geometric distribution on the horizontal projection plane. Specifically, this can be achieved by using the measuring tube 10 as the vertex and the venting tube 20 and the liquid extraction tube 30 as the two endpoints of the base. This layout reduces the liquid residue area between the tubes through spatial misalignment.

[0044] The included angle between the venting pipe 20 and the liquid extraction pipe 30 relative to the measuring pipe 10 is 30-120°, preferably 60°. This refers to the spatial angle range formed by the venting pipe 20 and the liquid extraction pipe 30 relative to the central axis of the measuring pipe 10. Specifically, this can be achieved by adjusting the positional offset of the connection point between the two pipes and the measuring pipe. This angle range balances the relationship between liquid flow resistance and flow direction stability.

[0045] In some of these embodiments, such as Figure 1 As shown, this application further proposes that the measuring tube 10, venting tube 20, and liquid extraction tube 30 are integrally molded structures made of transparent glass. The integral molding structure means that the measuring tube 10, venting tube 20, and liquid extraction tube 30 are formed as a single unit using a glass blowing process. Specifically, this can be achieved using segmented glass tube blow molding technology under high-temperature molten conditions. This process eliminates assembly gaps in split structures, preventing liquid residue at the interfaces. The transparent glass material refers to chemically inert borosilicate glass, which can be achieved by adjusting the ratio of silicon dioxide to boron oxide. This material maintains transparency while possessing resistance to acid and alkali corrosion.

[0046] Specifically, by designing the three functional pipelines as a seamless, integrated structure, the pipelines form a continuous, smooth inner wall surface. This prevents stagnation at the joints of traditional split structures during liquid flow, thus completely eliminating cleaning dead zones. The transparent glass material allows operators to directly observe the liquid flow within the pipeline, facilitating real-time monitoring of liquid level changes and verification of cleaning effectiveness. Its chemical stability ensures that it will not react with the test liquid during measurement, avoiding the introduction of measurement errors. This structural design gives the pipeline system overall mechanical strength, enabling it to withstand pressure fluctuations caused by repeated liquid pumping during automated operation.

[0047] Furthermore, this application also provides a viscosity measurement method based on the glass measuring tube that effectively prevents liquid over-rushing, such as... Figure 2 As shown, this viscosity measurement method mainly includes the following steps:

[0048] (1) Liquid aspiration: Open the VX3 two-position three-way valve to the VX3A valve line, open the VY3 two-position three-way valve to the VY3B valve line, close the VY4 valve, close the VX1 valve, close the VX2 valve, open the VY2 two-position three-way valve to the VY2B pipeline line, open the VY1 two-position three-way valve to the VY1A pipeline line, and use the syringe pump to aspirate the liquid and draw the drug solution into the measuring tube;

[0049] (2) Rinsing: Open the VY3 two-position three-way valve to the VY3A valve line, open the VX3 two-position three-way valve to the VX3B line, close the VY4 valve, close the VX1 valve, close the VX2 valve, open the VY2 two-position three-way valve to the VY2B line, open the VY1 two-position three-way valve to the VY1A line, and use the syringe pump to push the liquid in the measuring tube into the storage bulb for rinsing. Repeat this process by repeatedly pumping with the syringe pump to rinse the measuring tube 10.

[0050] (3) Drainage: When the rinsing is finished, the injection pump draws the liquid into the reservoir ball, the VY3 two-position three-way valve is opened to the VY3A valve line, the VX3 two-position three-way valve is opened to the VX3B pipeline line, the VY4 valve is open, the VX1A or VX1B valve is open, the VX2 valve is closed, the VY2 two-position three-way valve is opened to the VY2A pipeline line, the VY1 two-position three-way valve is opened to the VY1A pipeline line, the peristaltic pump M1 is turned on, and the liquid is drained from the measuring tube 10.

[0051] (4) Replace the washing solution sample with the measuring solution, and repeat steps (1) and (2) to push the liquid into the measuring tube 10;

[0052] (5) Measurement: The liquid falls freely to the upper fiber position and the timing starts from the upper fiber position and stops when the liquid falls back into the storage bulb 31; control the VY3 two-position three-way valve to open the VY3A valve line, the VX3 two-position three-way valve to open the VX3B pipeline line, the VY4 valve to open, the VX1 valve to close, the VX2 valve to close, the VY2 two-position three-way valve to open the VY2A pipeline line, and the VY1 two-position three-way valve to open the VY1A pipeline line to start the measurement.

[0053] (6) Drain the measuring solution: Repeat step (3);

[0054] The viscosity measurement method based on the glass measuring tube that can effectively prevent liquid over-rushing can quantitatively pump liquid using an injection pump, and can also automatically blow air and dry the measuring tube using a purge pump, realizing automated liquid loading and cleaning of the measuring tube. In addition, an extra buffer bulb is set on the measuring tube to effectively prevent liquid over-rushing and avoid measurement errors caused by liquid over-rushing in traditional viscometers.

[0055] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0056] Secondly, the accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0057] Finally, the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A glass measuring tube that can effectively prevent liquid overcurrent, characterized in that, The device includes a measuring tube (10), a venting tube (20), and a liquid extraction tube (30). The measuring tube (10) is characterized by having a liquid-holding bulb (11), a measuring bulb (12), a first buffer bulb (13), and a second buffer bulb (14) arranged sequentially from bottom to top. Its lower end is connected to the bottom of the liquid storage bulb (31) at the lower end of the liquid extraction tube (30) through a U-shaped bend (15). A drain pipe (16) is provided at the bottom of the U-shaped bend (15).

2. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The liquid-holding column bulb (11) is located at the lower end of the measuring tube (10), and its bottom is connected to one end of the U-shaped bend (15).

3. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The liquid-coated column bulb (11) and the measuring bulb (12) are connected by a capillary tube, and the connection point is smoothly transitioned by a tapered conical opening.

4. The glass measuring tube according to claim 3, which effectively prevents liquid overcurrent, is characterized in that, The capillary tube and its tapered constriction at the upper and lower ends are integrally formed with the measuring tube (10) around it, and the cross-section of the tapered constriction is an isosceles trapezoidal structure.

5. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The measuring bulb (12), the first buffer bulb (13), and the second buffer bulb (14) are arranged at intervals from bottom to top at the upper end of the measuring tube (10), and are connected to each other through the inner cavity of the tube.

6. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The size of the measuring bulb (12), the suspended liquid column bulb (11), the first buffer bulb (13) and the second buffer bulb (14) gradually decreases, and the first buffer bulb (13) and the second buffer bulb (14) are the same size.

7. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The venting tube (20) is arranged parallel to the inner side of the measuring tube (10), and its lower end is inclined downward and smoothly connected to the upper side of the liquid-coated column bulb (11).

8. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The liquid extraction tube (30) is arranged parallel to the right side of the measuring tube (10), and its lower end is connected to the top of the liquid storage bulb (31).

9. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The measuring tube (10), the venting tube (20) and the liquid extraction tube (30) are arranged in a triangular shape in cross-section, and the angle between the venting tube (20) and the liquid extraction tube (30) relative to the measuring tube (10) is 30-90°.

10. The glass measuring tube according to claim 1, which effectively prevents liquid overcurrent, is characterized in that, The measuring tube (10), venting tube (20) and liquid extraction tube (30) are integrally formed and are made of transparent glass.

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