Purging and trapping device for water quality detection

Abstract

The invention provides a purging and trapping device for water quality detection, which comprises a bubble generation assembly, the bubble generation assembly comprises a first bubble plate and a second bubble plate, the first bubble plate and the second bubble plate are located in a spherical pipe, and the positions of the first bubble plate and the second bubble plate can be switched in the spherical pipe, the aperture of the first bubble plate is larger than that of the second bubble plate. In a mixed gas working condition, the outer wall of the first bubble plate is tightly attached to the interior of the spherical pipe, and the second bubble plate is separated from the inner wall of the spherical pipe; and in a pure carrier gas working condition, the outer wall of the second bubble plate is tightly attached to the inner wall of the spherical pipe, and the first bubble plate is separated from the inner wall of the spherical pipe. Therefore, the first bubble plate and the second bubble plate with different apertures are adopted, so that the mixed gas can smoothly pass through under the working condition of the mixed gas; under the working condition of pure carrier gas, the mass transfer efficiency is improved, and the purging capacity on target substances in a water sample is enhanced.

Description

Technical Field

[0001] The present invention relates to the field of environmental analysis instruments, and particularly to a purge and trap device for water quality detection. Background Art

[0002] The purge and trap device for water quality detection is used for pre-treating water samples to improve the detection accuracy. The purge and trap device for water quality detection blows bubbles in the water sample by means of a carrier gas through a bubble plate. The carrier gas comes into full contact with the water sample, purging trace target substances such as volatile organic compounds in the water into the gas phase. These volatile substances are then adsorbed and enriched by a trap, separated from other impurities such as water. Subsequently, the trap is heated and purged with the carrier gas to desorb the concentrated target substances and send them into the detection instrument, realizing the accurate detection of trace pollutants in water and providing a key basis for judging the water quality status.

[0003] In the existing water quality detection process, if the target substances in the water sample are highly volatile and the detection accuracy requirements mainly focus on the rapid and stable detection of the target substances, pure carrier gas can be used at this time.

[0004] When the content of the target volatile substances in the water sample is low and it is necessary to improve the purge efficiency and trapping effect, a mixed gas needs to be used. The mixed gas can utilize the characteristics of different gases to enhance the purging ability of the target substances. For example, some organic pollutants have low solubility and weak volatility in water, and it is difficult to purge them out efficiently with a single pure carrier gas, which takes a long time to completely purge such substances out of the water. The other gas components in the mixed gas can improve the mass transfer process between the bubbles and the liquid, improving the purge efficiency.

[0005] In the purge and trap process of water quality detection, when purging the water sample with pure carrier gas, if a large-aperture bubble plate is used, the large bubbles generated have a small contact area with the water sample, resulting in low mass transfer efficiency and difficulty in efficiently transferring the volatile substances in the water sample to the gas phase, which damages the detection sensitivity and accuracy. When purging with a mixed gas, since the mixed gas has strong viscosity, if a small-aperture bubble plate is still used, the gas flow resistance will be too large, making the mixed gas unable to pass smoothly and seriously hindering the normal progress of the purge process.

[0006] The information disclosed in the background art part of the present invention is only intended to deepen the understanding of the general background art of the present invention, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0007] Based on this, it is necessary to provide a purge and trap device for water quality detection to address the problem of poor adaptability of the bubble plate caused by differences in gas properties in the current purge and trap device for water quality detection.

[0008] The above object is achieved by the following technical solutions: A purge and trap device for water quality detection, comprising: A spherical tube; A purge assembly, the purge assembly includes a pure gas connecting pipe and a mixed gas connecting pipe. The pure gas connecting pipe is used to introduce pure carrier gas, and the mixed gas connecting pipe is used to introduce mixed gas.

[0009] A bubble generation assembly, the bubble generation assembly includes a first bubble plate and a second bubble plate. The first bubble plate and the second bubble plate are located inside the spherical tube, and the first bubble plate and the second bubble plate can switch positions inside the spherical tube. The pore diameter of the first bubble plate is larger than that of the second bubble plate.

[0010] Wherein, when in the mixed gas working condition, the outer wall of the first bubble plate is closely attached to the inside of the spherical tube, and the second bubble plate is separated from contacting the inner wall of the spherical tube, that is, the first bubble plate is in a sealed state and the second bubble plate is in an open state; when in the pure carrier gas working condition, the outer wall of the second bubble plate is closely attached to the inner wall of the spherical tube, and the first bubble plate is separated from contacting the inner wall of the spherical tube, that is, the second bubble plate is in a sealed state and the first bubble plate is in an open state.

[0011] A driving mechanism, the driving mechanism is used to switch the working states of the first bubble plate and the second bubble plate.

[0012] In one embodiment, the driving mechanism includes a rotating frame. The first bubble plate and the second bubble plate are slidably connected to the rotating frame, and the rotating frame is used to drive the first bubble plate and the second bubble plate to switch positions by rotation.

[0013] In one embodiment, the driving mechanism includes a weight structure, and the weight structure is used to adjust the distance between the first bubble plate and the second bubble plate and the inner wall of the spherical tube.

[0014] In one embodiment, the rotating frame is provided with a plurality of adjusting cylinders. The first bubble plate and the second bubble plate are slidably connected to the adjusting cylinders. The weight structure includes a plurality of weight blocks. The weight blocks can slide inside the adjusting cylinders. The weight blocks, the first bubble plate and the adjusting cylinders enclose a first chamber, and the weight blocks, the second bubble plate and the adjusting cylinders enclose a second chamber. The weight blocks, the adjusting cylinders, the first chamber and the second chamber are used to drive the first bubble plate and the second bubble plate to expand and contract under the action of gravity to adapt to different working states.

[0015] In one embodiment, a first elastic member is disposed between the counterweight and the adjusting cylinder, and the elastic force of the first elastic member always causes the counterweight to be located at a preset position or have a tendency to approach the preset position.

[0016] In one embodiment, it includes a flow guiding assembly, and the flow guiding assembly is located between the first bubble plate and the second bubble plate, and the flow guiding assembly is used for uniformly mixing the mixed gas.

[0017] In one embodiment, the flow guiding assembly includes a plurality of flow guiding plates, the flow guiding plates are rotatably connected to the inner wall of the spherical tube, and the second bubble plate is provided with a magnetic control assembly. The magnetic control assembly controls the rotation angle of the flow guiding plate through magnetic interaction. Under the condition of the mixed gas, the flow guiding plate is inclined to form a mixing flow channel; under the condition of pure carrier gas, the flow guiding plate is vertical to reduce the flow resistance.

[0018] In one embodiment, the flow guiding assembly includes a limiting structure, and the limiting structure is used to restrict the maximum rotation angle of the flow guiding plate to stabilize the air flow direction.

[0019] In one embodiment, the driving mechanism includes a sliding block, and a sliding groove is provided on the outer wall of the spherical tube. When the first bubble plate and the second bubble plate are in a switching state, the sliding block and the sliding groove are used to make the flow guiding plate in a tightened state to avoid interference of the flow guiding plate with the first bubble plate and the second bubble plate, and after the first bubble plate and the second bubble plate complete the switching, the sliding block and the sliding groove make the flow guiding plate in an opened state.

[0020] In one embodiment, a second elastic member is disposed between the plurality of flow guiding plates, and two ends of the second elastic member are respectively connected to two adjacent flow guiding plates, and the elastic force of the second elastic member always causes the two flow guiding plates to move away from each other or have a tendency to move away from each other.

[0021] The beneficial effects of the present invention are: The present invention provides a purge and trap device for water quality detection, comprising: a bubble generation assembly, which includes a first bubble plate and a second bubble plate. The first bubble plate and the second bubble plate are located inside a spherical tube, and the first bubble plate and the second bubble plate can switch positions inside the spherical tube. The aperture of the first bubble plate is larger than that of the second bubble plate. When in a mixed gas condition, the outer wall of the first bubble plate closely adheres to the inside of the spherical tube, and the second bubble plate disengages from contact with the inner wall of the spherical tube; when in a pure carrier gas condition, the outer wall of the second bubble plate closely adheres to the inner wall of the spherical tube, and the first bubble plate disengages from contact with the inner wall of the spherical tube. Thus, by using the first bubble plate and the second bubble plate with different apertures, the smooth passage of the mixed gas is ensured under the mixed gas condition; under the pure carrier gas condition, the mass transfer efficiency is improved, and the purging ability of the target substances in the water sample is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. 1 is a schematic structural diagram of a purge and trap device for water quality detection provided by an embodiment of the present invention; Figure 2 is Figure 1 a side view of the purge and trap device for water quality detection in FIG. 1; Figure 3 is Figure 2 a schematic cross-sectional view taken along line A-A of the purge and trap device for water quality detection in FIG. 1; Figure 4 is Figure 3 a partial enlarged view at position D of the purge and trap device for water quality detection in FIG. 1; Figure 5 FIG. 2 is a schematic structural diagram of a spherical tube of a purge and trap device for water quality detection provided by an embodiment of the present invention; Figure 6 is Figure 5 a schematic cross-sectional view taken along line B-B of the spherical tube of the purge and trap device for water quality detection in FIG. 2; Figure 7 is Figure 5 a schematic cross-sectional view taken along line C-C before the switching of the first bubble plate and the second bubble plate of the spherical tube of the purge and trap device for water quality detection in FIG. 2; Figure 8 is Figure 5 a schematic cross-sectional view taken along line C-C during the switching of the first bubble plate and the second bubble plate of the spherical tube of the purge and trap device for water quality detection in FIG. 2; Figure 9 is Figure 5 a schematic cross-sectional view taken along line C-C after the switching of the first bubble plate and the second bubble plate of the spherical tube of the purge and trap device for water quality detection in FIG. 2; Figure 10 FIG. 3 is an exploded view of a bubble generation assembly in a purge and trap device for water quality detection provided by an embodiment of the present invention; Figure 11Structural schematic diagram of the limiting structure in the purge and trap device for water quality detection provided by an embodiment of the present invention.

[0023] Wherein: 100, purge assembly; 110, pure gas connecting pipe; 120, mixed gas connecting pipe; 200, bubble generation assembly; 210, first bubble plate; 220, second bubble plate; 221, magnetic control assembly; 300, drive mechanism; 310, rotating frame; 311, adjusting cylinder; 320, counterweight structure; 321, counterweight block; 322, first elastic member; 330, sliding block; 340, sliding groove; 400, flow guiding assembly; 410, flow guiding plate; 411, magnetic block; 412, connecting block; 420, limiting structure; 430, second elastic member; 500, spherical tube. Detailed implementation manners

[0024] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meanings. The "connection" and "coupling" mentioned in the present invention, unless otherwise specifically stated, both include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention.

[0026] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0027] The following will refer to Figures 1 - 11 to describe the purge and trap device for water quality detection provided by the embodiments of the present invention.

[0028] As Figures 1 - 4 shown, the purge and trap device for water quality detection provided by the embodiments of the present invention is particularly suitable for the purge and trap of volatile gases in various water samples for water quality detection. Of course, it can also be applicable to the purge and trap operations of other samples containing volatile gases such as soil samples.

[0029] Specifically, the purge and trap device for water quality detection provided by the embodiments of the present invention includes a purge assembly 100, a bubble generation assembly 200, and a drive mechanism 300.

[0030] The purge assembly 100 is used to provide purge power and a transport carrier. The purge assembly 100 introduces a carrier gas (such as pure carrier gas or mixed gas) to carry out the volatile substances in the water sample. The carrier gas flows in the device to form a driving force, prompting the volatile substances to transfer from the liquid phase to the gas phase, realizing the separation and enrichment of the target substances in the water sample.

[0031] The bubble generation assembly 200 is used to generate uniform and stable bubbles. When the carrier gas passes through the bubble generation assembly 200, it will be dispersed into tiny bubbles and enter the water sample. These tiny bubbles have a large specific surface area, which can increase the contact area between the carrier gas and the water sample, improve the mass transfer efficiency, enable the volatile substances to transfer from the water to the carrier gas more fully, and thus improve the effect of purge and trap and the accuracy of detection.

[0032] The drive mechanism 300, as the power source in the purge and trap device for water quality detection, provides power for the movement of other components, including but not limited to providing carrier gas for the purge assembly 100.

[0033] It can be understood that the drive mechanism 300 can be a common drive form, such as an electric motor, an internal combustion engine, etc. The power source in the drive mechanism 300 can be centralized, and the power is transmitted to other components through a transmission structure; the power source can also be decentralized, and multiple decentralized power sources drive each component to act respectively.

[0034] During the purge and trap process of water quality detection, different purge gases need to be selected due to the property differences of the volatile substances in the water sample. When purging with pure carrier gas, a small-aperture bubble plate can generate stable tiny bubbles, greatly increasing the gas-liquid contact area, effectively improving the mass transfer efficiency of the volatile substances transferring from the water sample to the gas phase, and ensuring the sensitivity and accuracy of detection.

[0035] However, when purging with a mixed gas, due to the strong viscosity of the mixed gas, if the small-aperture bubble plate continues to be used, it will cause too large a gas flow resistance and affect the purge process. At this time, a large-aperture bubble plate needs to be used to ensure that the mixed gas can pass through smoothly.

[0036] However, when the large-aperture bubble plate is used for purging with pure carrier gas, the large bubbles formed have poor stability and are prone to rupture, and cannot effectively and stably carry the substances to be detected in water, resulting in a low mass transfer rate.

[0037] Based on this, the bubble generation assembly 200 includes a first bubble plate 210 and a second bubble plate 220. The first bubble plate 210 is for the mixed gas to pass through, and the second bubble plate 220 is for the pure carrier gas to pass through.

[0038] Specifically, the purging assembly 100 includes a pure gas connecting pipe 110 and a mixed gas connecting pipe 120. The pure gas connecting pipe 110 is for introducing pure carrier gas, and the mixed gas connecting pipe 120 is for introducing mixed gas. A Venturi tube is provided at the connection of the pure gas connecting pipe 110 and the mixed gas connecting pipe 120.

[0039] The main body of the Venturi tube is composed of a converging section, a throat section, and a diverging section connected in sequence.

[0040] When various gases from the purging assembly 100 meet at the Venturi tube, the various gases enter the Venturi tube at their respective initial flow rates and pressures.

[0041] In the converging section, as the cross-sectional area of the pipeline gradually decreases, the gas flow rate increases and the pressure decreases accordingly. When entering the throat section, the gas flow rate reaches the maximum value and the pressure drops to the lowest, and a low-pressure area is formed in the throat area at this time. Gases from different sources are strongly sucked and mixed at the throat.

[0042] Due to the intensified Brownian motion of gas molecules under high-speed flow and low-pressure environment, the components in the pure carrier gas and the mixed gas can diffuse and penetrate more fully with each other, realizing preliminary mixing.

[0043] In the diverging section, the cross-sectional area of the pipeline gradually increases, the gas flow rate slows down, and the pressure rises. The mixed gas flows out of the Venturi tube in a relatively stable state and enters the subsequent purge and trap process.

[0044] The purge and trap bottle is set as a spherical tube 500 structure. The spherical tube 500 is used to hold the water sample and provide a reaction space for the purge and trap process. The first bubble plate 210 and the second bubble plate 220 are located inside the spherical tube 500, and the first bubble plate 210 and the second bubble plate 220 can switch positions inside the spherical tube 500. The aperture of the first bubble plate 210 is larger than that of the second bubble plate 220.

[0045] When in the mixed gas condition, the outer wall of the first bubble plate 210 is in close contact with the inside of the spherical tube 500, and the second bubble plate 220 is disengaged from the inner wall of the spherical tube 500. That is, the first bubble plate 210 is in a sealed state, and the second bubble plate 220 is in an open state. When in the pure carrier gas condition, the outer wall of the second bubble plate 220 is in close contact with the inner wall of the spherical tube 500, and the first bubble plate 210 is disengaged from the inner wall of the spherical tube 500. That is, the second bubble plate 220 is in a sealed state, and the first bubble plate 210 is in an open state.

[0046] When in the mixed gas condition, due to its strong viscosity, the mixed gas requires a larger flow space to reduce resistance. At this time, the outer wall of the first bubble plate 210 is in close contact with the inside of the spherical tube 500 and is in a sealed state. The mixed gas can only enter the water sample inside the spherical tube 500 through the larger apertures on the first bubble plate 210. The bubble plate with larger apertures enables the mixed gas to pass through more smoothly, reducing the problem of poor flow caused by gas viscosity. At the same time, the second bubble plate 220 is disengaged from the inner wall of the spherical tube 500 and is in an open state, not causing a large obstruction to the purging path of the mixed gas and ensuring the high efficiency of the mixed gas purging process.

[0047] When in the pure carrier gas condition, the pure carrier gas needs to form tiny and stable bubbles during purging to increase the contact area with the water sample. Therefore, at this time, the outer wall of the second bubble plate 220 is in close contact with the inner wall of the spherical tube 500 and enters a sealed state. The pure carrier gas enters the water sample through the smaller apertures on the second bubble plate 220, thereby generating tiny bubbles and effectively improving the mass transfer efficiency. At the same time, the first bubble plate 210 is disengaged from the inner wall of the spherical tube 500 and is in an open state, avoiding unnecessary interference with the flow of the pure carrier gas.

[0048] During the operation of the purge and trap device, after the water sample is injected into the spherical tube 500, the working condition is switched according to the preset detection program and the type of gas used.

[0049] If mixed gas purging is required, the driving mechanism 300 adjusts the first bubble plate 210 to a sealed state. The mixed gas enters from the mixed gas connection pipe 120, passes through the first bubble plate 210 and enters the water sample for purging work, taking out some substances in the water sample that are easily purged out by the mixed gas.

[0050] When it is necessary to switch to pure carrier gas purging, the driving mechanism 300 rotates to switch the positions of the first bubble plate 210 and the second bubble plate 220, so that the second bubble plate 220 is switched to a sealed state, and at the same time the first bubble plate 210 is switched to an open state. The pure carrier gas enters from the pure gas connection pipe 110 and forms tiny bubbles through the second bubble plate 220 to purge the water sample.

[0051] Thus, by setting the purge and trap bottle as the spherical tube 500 and adopting the first bubble plate 210 and the second bubble plate 220 with different pore diameters, the adaptability problem of the bubble plate of the traditional device when purging gases with different properties is solved. Under the mixed gas condition, the smooth passage of the mixed gas is ensured, and the unsmooth purging caused by gas viscosity is avoided; under the pure carrier gas condition, the mass transfer efficiency is improved, and the purging ability of the target substances in the water sample is enhanced.

[0052] Furthermore, as Figures 1 - 4 shown, the driving mechanism 300 includes a rotating frame 310, and the rotating frame 310 is used to drive the first bubble plate 210 and the second bubble plate 220 to switch positions by rotation.

[0053] Specifically, the rotating frame 310 is slidably connected to the first bubble plate 210 and the second bubble plate 220, and the rotating frame 310 can rotate around its own central axis. When the rotating frame 310 rotates, it can synchronously drive the first bubble plate 210 and the second bubble plate 220 to switch positions, and the switching process is stable and reliable.

[0054] When mixed gas purging is required, the rotating frame 310 rotates to move the first bubble plate 210 above the second bubble plate 220, and the driving mechanism 300 drives the first bubble plate 210 and the second bubble plate 220 to move upward, so that the first bubble plate 210 is closely attached to the inner wall of the spherical tube 500 and is in a sealed state, and the second bubble plate 220 is separated from the inner wall of the spherical tube 500 and is in an open state.

[0055] When it is necessary to adjust to the pure carrier gas purging condition, the driving mechanism 300 first drives the first bubble plate 210 to move downward, then the rotating frame 310 rotates to adjust the second bubble plate 220 above the first bubble plate 210. After the rotation of the rotating frame 310 is completed, the driving mechanism 300 drives the second bubble plate 220 and the first bubble plate 210 to move upward. The second bubble plate 220 is closely attached to the inner wall of the spherical tube 500 and is in a sealed state, and the first bubble plate 210 is in an open state, avoiding interference with the flow of the pure carrier gas.

[0056] Thus, by setting the rotating frame 310, the positions of the first bubble plate 210 and the second bubble plate 220 can be switched quickly and accurately, improving the conversion efficiency of the purge and trap device between different gas conditions.

[0057] In other embodiments, the driving mechanism 300 can be directly connected to the first bubble plate 210 and the second bubble plate 220 to realize the regulation of the working states of the first bubble plate 210 and the second bubble plate 220.

[0058] During the actual operation, when the purge and trap device for water quality detection needs to switch from one gas purge condition to another, for example, from a pure carrier gas condition to a mixed gas condition, the rotational movement is caused by the transmission component, directly pushing the first bubble plate 210 and the second bubble plate 220 to switch positions.

[0059] In one embodiment, as Figures 5 - 9 shown, the driving mechanism 300 includes a counterweight structure 320, and the counterweight structure 320 is used to adjust the distance between the first bubble plate 210 and the second bubble plate 220 and the inner wall of the spherical tube 500.

[0060] Specifically, the rotating frame 310 is provided with a plurality of adjusting cylinders 311, and the first bubble plate 210 and the second bubble plate 220 are slidably connected to the adjusting cylinders 311, so that the first bubble plate 210 and the second bubble plate 220 can flexibly perform telescopic movement within the adjusting cylinders 311.

[0061] The counterweight structure 320 includes a plurality of counterweight blocks 321. The counterweight blocks 321 are located inside the adjusting cylinders 311, and the counterweight blocks 321 can slide relative to the adjusting cylinders 311. The counterweight blocks 321 are provided with third elastic members, and the third elastic members can fit against the inner walls of the adjusting cylinders 311, and the third elastic members can drive the counterweight blocks 321 to slide along the inner walls of the adjusting cylinders 311.

[0062] A first chamber and a second chamber are formed within the adjusting cylinder 311. The first chamber connects the counterweight block 321 and the first bubble plate 210, and the second chamber connects the counterweight block 321 and the second bubble plate 220. So that the counterweight block 321 can drive the first bubble plate 210 and the second bubble plate 220 to expand and contract under the action of gravity to adapt to different working states.

[0063] When it is necessary to adjust to the mixed gas condition and the first bubble plate 210 needs to closely fit the inner wall of the spherical tube 500, as the position of the rotating frame 310 changes, the counterweight block 321 begins to slide within the adjusting cylinder 311 under the action of gravity.

[0064] The position adjustment of the rotating frame 310 causes the counterweight block 321 to slide in the vertical direction, and the counterweight block 321 slides in the direction that increases the pressure in the first chamber. The volume of the first chamber decreases and the pressure increases, thereby pushing the first bubble plate 210 to extend outwards until the outer wall of the first bubble plate 210 closely fits the inner wall of the spherical tube 500, forming a sealed state; at the same time, the volume of the second chamber increases and the pressure decreases, and the second bubble plate 220 correspondingly contracts and disengages from the contact with the inner wall of the spherical tube 500, being in an open state.

[0065] Similarly, when it is necessary to switch to the pure carrier gas condition, the rotating frame 310 adjusts its position again, and the counterweight 321 slides, increasing the pressure in the second chamber and decreasing the pressure in the first chamber. The second bubble plate 220 extends and closely fits against the inner wall of the spherical tube 500, and the first bubble plate 210 contracts to complete the switching of the working state.

[0066] Thus, through the counterweight structure 320, the distances between the first bubble plate 210 and the second bubble plate 220 and the inner wall of the spherical tube 500 are automatically and precisely adjusted. The positions of the bubble plates can be quickly and accurately switched according to different working states, improving the response speed of the device and the convenience of operation.

[0067] At the same time, since the counterweight structure 320 mainly relies on gravity and chamber pressure to drive the expansion and contraction of the bubble plates, it avoids the risk of failures caused by complex transmission mechanisms and electronic components, reduces the maintenance cost of the equipment, and improves the stability and service life of the device.

[0068] In one embodiment, during the process where the driving mechanism 300 drives the first bubble plate 210 and the second bubble plate 220 to rotate and switch positions, in order to ensure that the bubble plates closely fit against the inner wall of the spherical tube 500 in the working state and achieve a good sealing effect, there is a certain contact pressure between the bubble plates and the inner wall of the spherical tube 500, which causes friction between the first bubble plate 210 and the second bubble plate 220 and the inner wall of the spherical tube 500, resulting in increased wear of the bubble plates and the inner wall of the spherical tube 500 and shortening the service life of the purge and trap device.

[0069] As Figures 5 - 9 shown, in order to reduce the friction between the first bubble plate 210 and the second bubble plate 220 and the spherical tube 500 during the rotational switching, a first elastic member 322 is provided between the counterweight 321 and the adjusting cylinder 311.

[0070] Specifically, the elastic force of the first elastic member 322 always makes the counterweight 321 located at a preset position or tend to move towards the preset position.

[0071] When the rotating frame 310 drives the adjusting cylinder 311 to rotate and approaches the horizontal position, the counterweight 321, which was originally distributed along the axial direction of the adjusting cylinder 311 under the action of gravity, now has the direction of gravity nearly perpendicular to the axis of the adjusting cylinder 311, and the effect of gravity on the position of the counterweight 321 in the adjusting cylinder 311 decreases. Due to its inherent elastic restoring force characteristic, the first elastic member 322 pushes the counterweight 321 towards the middle position of the adjusting cylinder 311.

[0072] As the counterweight 321 moves towards the middle position, the pressure distribution in the first chamber and the second chamber is adjusted. The acting force generated by the pressure difference causes the distances between the first bubble plate 210 and the second bubble plate 220 and the inner wall of the spherical tube 500 to gradually reach the preset positions. The preset positions are the positions where the first bubble plate 210 and the second bubble plate 220 are fully away from the inner wall of the spherical tube 500. The rotating frame 310 continues to rotate to complete the position switching of the bubble plates. Thus, when the first bubble plate 210 and the second bubble plate 220 rotate, the contact area and contact pressure between the first bubble plate 210 and the second bubble plate 220 and the inner wall of the spherical tube 500 are reduced, and the friction force is lowered.

[0073] After the switching is completed, the adjusting cylinder 311 leaves the horizontal position. Under the action of gravity, the counterweight 321 overcomes the elastic force of the first elastic member 322 and moves to the corresponding working position again. The first bubble plate 210 and the second bubble plate 220 are stretched or contracted again to the corresponding working states of being in contact with or separated from the inner wall of the spherical tube 500 to adapt to the new purging gas working conditions.

[0074] Thus, by providing the first elastic member 322, the friction between the first bubble plate 210 and the second bubble plate 220 and the spherical tube 500 is effectively reduced, and the wear speed of the components is greatly slowed down.

[0075] In one embodiment, as Figures 5 - 11 shown, in order to prevent the unevenness of the mixed gas from resulting in different contact opportunities between different volatile substances and the gas in the water sample, the purge and trap device for water quality detection provided by the embodiment of the present invention includes a flow guiding assembly 400, and the flow guiding assembly 400 is used for uniformly mixing the mixed gas.

[0076] Specifically, the flow guiding assembly 400 is located between the first bubble plate 210 and the second bubble plate 220. The flow guiding assembly 400 includes a plurality of flow guiding plates 410 and a limiting structure 420. The plurality of flow guiding plates are rotatably connected to the inner wall of the spherical tube 500 at intervals. Magnetic blocks 411 with magnetism are arranged on both sides of the flow guiding plate 410. The limiting structure 420 is used to restrict the maximum rotation angle of the flow guiding plate 410 to stabilize the gas flow direction.

[0077] The second bubble plate 220 is provided with a magnetic control assembly 221. The magnetic control assembly 221 and the flow guiding plate 410 are in a staggered distribution state in the vertical direction. The magnetic control assembly 221 controls the rotation of the flow guiding plate 410 through magnetic interaction.

[0078] When in the mixed gas purging condition, the second bubble plate 220 is located below the flow guide plate 410. At this time, the magnetic control component 221 and the magnetic block 411 at the end of the flow guide plate 410 that is relatively close are magnetically repulsive. Under the action of the repulsive force, the flow guide plate 410 gradually tilts. Under the action of the limit structure 420, multiple flow guide plates 410 tilt by the same preset angle to form a mixed flow channel, forcing the mixed gas to change its flow direction, and greatly increasing the collision frequency between gas molecules of different components, thus greatly improving the uniformity of the mixed gas.

[0079] When switching to the pure carrier gas purging condition, the second bubble plate 220 moves above the flow guide plate 410. At this time, the magnetic control component 221 and the magnetic block 411 at the end of the flow guide plate 410 that is relatively close are magnetically attractive. The magnetic force of the attraction between opposite magnetic poles causes the flow guide plate 410 to quickly rotate to the vertical state. For the pure carrier gas, the vertical flow guide plate 410 can minimize the resistance during the flow of the pure carrier gas, ensuring that the pure carrier gas can pass through at a stable and efficient flow rate, and improving the purging efficiency.

[0080] Thus, through the flow guide component 400, in terms of mixed gas purging, the flow guide plate 410 rotates and tilts, enabling the mixed gas to be evenly mixed and ensuring that various volatile substances in the water sample can be evenly contacted with the mixed gas. In terms of pure carrier gas purging, by making the flow guide plate 410 vertical, the flow resistance of the pure carrier gas is reduced, and the purging efficiency is improved.

[0081] Further, as Figures 5 - 11 shown, the driving mechanism 300 includes a sliding block 330. The outer wall of the spherical tube 500 is provided with a sliding groove 340. When the first bubble plate 210 and the second bubble plate 220 are in the switching state, the sliding block 330 and the sliding groove 340 are used to make the flow guide plate 410 in a tightened state to prevent multiple flow guide plates 410 from interfering with the position switching of the first bubble plate 210 and the second bubble plate 220, and after the first bubble plate 210 and the second bubble plate 220 complete the switching, the sliding block 330 and the sliding groove 340 make the flow guide plate 410 in an open state.

[0082] Specifically, multiple flow guide plates 410 are set as multiple identical units, enabling the flow guide plates 410 within the unit to move towards both ends of the rotating frame 310 to complete contraction.

[0083] The sliding block 330 is made of a magnetic material. The flow guide plate 410 is provided with a connecting block 412. The sliding block 330 drives the connecting block 412 of the flow guide plate 410 corresponding to the sliding block 330 in the unit to move through magnetism, thereby causing the multiple flow guide plates 410 in the unit to contract, ensuring that the flow guide plates 410 do not interfere during the switching process of the first bubble plate 210 and the second bubble plate 220.

[0084] When the first bubble plate 210 and the second bubble plate 220 are in the switching state, the sliding block 330 slides forward along the sliding groove 340 under the power of the driving mechanism 300. At this time, the sliding block 330 drives the flow guiding plate 410 to move and contract.

[0085] During the switching process of the first bubble plate 210 and the second bubble plate 220, the flow guiding plate 410 is in a contracted state, avoiding interference of the flow guiding plate 410 with the first bubble plate 210 and the second bubble plate 220 whose positions are being switched.

[0086] After the first bubble plate 210 and the second bubble plate 220 complete the switching, the sliding block 330 slides backward along the sliding groove 340, causing the flow guiding plate 410 to open and return to the working state.

[0087] Thus, by adjusting the flow guiding plate 410 through the sliding block 330 and the sliding groove 340, the interference problem that may occur between the first bubble plate 210 and the second bubble plate 220 and the flow guiding plate 410 during the switching process is effectively prevented, improving the stability and reliability of the device operation.

[0088] In one embodiment, as Figures 5 - 9 shown, a second elastic member 430 is provided between multiple flow guiding plates 410. Two ends of the second elastic member 430 are respectively connected to two adjacent flow guiding plates 410. The second elastic member 430 is used to make the multiple flow guiding plates 410 evenly distributed.

[0089] Specifically, the elastic force of the second elastic member 430 always makes two flow guiding plates 410 move away from each other or tend to move away from each other.

[0090] When the device is working normally, under the action of the second elastic member 430, a certain interval distance is maintained between adjacent flow guiding plates 410, and they are evenly distributed between the first bubble plate 210 and the second bubble plate 220.

[0091] When the first bubble plate 210 and the second bubble plate 220 are in the switching state, to avoid interference of the flow guiding plate 410 with the first bubble plate 210 and the second bubble plate 220, when the sliding block 330 slides forward along the sliding groove 340 on the outer wall of the spherical tube 500, the flow guiding plate 410 contracts against the elastic force of the second elastic member 430, and multiple flow guiding plates 410 approach each other and are in a tightened state, avoiding interference with the first bubble plate 210 and the second bubble plate 220 whose positions are being switched, and ensuring the smoothness and accuracy of the switching process.

[0092] After the switching between the first bubble plate 210 and the second bubble plate 220 is completed, the sliding block 330 slides reversely along the sliding groove 340, and the elastic force of the second elastic member 430 is released. Under the action of the elastic force of the second elastic member 430 and the sliding block 330, the plurality of flow guiding plates 410 quickly return to the open state where they are away from each other and are evenly redistributed between the first bubble plate 210 and the second bubble plate 220.

[0093] Thus, by providing the second elastic member 430, it is ensured that the flow guiding plates 410 can be evenly distributed during normal operation.

[0094] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0095] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A purge and trap device for water quality detection, characterized in that, Comprising: Spherical tube; Purge assembly, the purge assembly includes a pure gas connecting pipe and a mixed gas connecting pipe, the pure gas connecting pipe is used for introducing pure carrier gas, and the mixed gas connecting pipe is used for introducing mixed gas; Bubble generation assembly, the bubble generation assembly includes a first bubble plate and a second bubble plate, the first bubble plate and the second bubble plate are located inside the spherical tube, and the first bubble plate and the second bubble plate can switch positions inside the spherical tube, and the aperture of the first bubble plate is larger than that of the second bubble plate; Wherein, in the mixed gas working condition, the outer wall of the first bubble plate is closely attached to the inside of the spherical tube, and the second bubble plate is separated from the inner wall of the spherical tube, that is, the first bubble plate is in a sealed state and the second bubble plate is in an open state; in the pure carrier gas working condition, the outer wall of the second bubble plate is closely attached to the inner wall of the spherical tube, and the first bubble plate is separated from the inner wall of the spherical tube, that is, the second bubble plate is in a sealed state and the first bubble plate is in an open state; Drive mechanism, the drive mechanism is used to switch the working states of the first bubble plate and the second bubble plate.

2. The purge and trap device for water quality detection according to claim 1, characterized in that, The drive mechanism includes a rotating frame, the first bubble plate and the second bubble plate are slidably connected to the rotating frame, and the rotating frame is used to drive the first bubble plate and the second bubble plate to switch positions by rotation.

3. The purge and trap device for water quality detection according to claim 2, characterized in that, The drive mechanism includes a weight structure, and the weight structure is used to adjust the distance between the first bubble plate and the second bubble plate and the inner wall of the spherical tube.

4. A purge and trap device for water quality detection according to claim 3, characterized in that, The rotating frame is provided with a plurality of adjusting cylinders, the first bubble plate and the second bubble plate are slidably connected to the adjusting cylinders, the weight structure includes a plurality of weight blocks, the weight blocks are slidably located inside the adjusting cylinders, and the weight blocks, the first bubble plate and the adjusting cylinders enclose a first chamber, and the weight blocks, the second bubble plate and the adjusting cylinders enclose a second chamber. The weight blocks, the adjusting cylinders, the first chamber and the second chamber are used to drive the first bubble plate and the second bubble plate to expand and contract under the action of gravity to adapt to different working states.

5. A purge and trap device for water quality detection according to claim 4, characterized in that, A first elastic member is arranged between the weight block and the adjusting cylinder, and the elastic force of the first elastic member always makes the weight block located at a preset position or tend to approach the preset position.

6. A purge and trap device for water quality detection according to claim 1, characterized in that, Including a flow guiding assembly, the flow guiding assembly is located between the first bubble plate and the second bubble plate, and the flow guiding assembly is used to uniformly mix the mixed gas.

7. The purge and trap device for water quality detection according to claim 6, characterized in that, The flow guiding assembly includes a plurality of flow guiding plates, the flow guiding plates are rotatably connected to the inner wall of the spherical tube, the second bubble plate is provided with a magnetic control assembly, and the magnetic control assembly controls the rotation angle of the flow guiding plates through magnetic interaction. In the mixed gas working condition, the flow guiding plates are inclined to form a mixed flow channel; in the pure carrier gas working condition, the flow guiding plates are vertical to reduce the flow resistance.

8. A purge and trap device for water quality detection according to claim 7, characterized in that, The flow guiding assembly includes a limiting structure, and the limiting structure is used to restrict the maximum rotation angle of the flow guiding plates to stabilize the gas flow direction.

9. A purge and trap device for water quality detection according to claim 7, characterized in that, The driving mechanism includes a sliding block. A sliding groove is provided on the outer wall of the spherical tube. When the first bubble plate and the second bubble plate are in a switching state, the sliding block and the sliding groove are used to make the flow guide plate in a tightened state to avoid interference of the flow guide plate with the first bubble plate and the second bubble plate, and after the switching between the first bubble plate and the second bubble plate is completed, the sliding block and the sliding groove make the flow guide plate in an open state.

10. A purge and trap device for water quality detection according to claim 9, characterized in that, A second elastic member is provided between multiple flow guide plates. Two ends of the second elastic member are respectively connected to two adjacent flow guide plates. The elastic force of the second elastic member always makes the two flow guide plates move away from each other or tend to move away from each other.

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