Chemical detection device for harmful substances of toys

Abstract

The invention provides a chemical detection device for harmful substances of toys, and relates to chemical detection, the chemical detection device comprises a liquid chromatograph body, the liquid chromatograph body is provided with an extraction column, the extraction column comprises a column body, the position, close to the incident flow end of a first sieve plate, of the column body is provided with a pollution discharge hole, the pollution discharge hole is provided with a non-return structure, and the outer side of a buffer chamber is sleeved with an elastic sleeve; the outer side of the extraction column is sleeved with a shell, a liquid channel is formed between the shell and the extraction column, the liquid channel is communicated with a circulation branch, and a filtering structure and a liquid pump are arranged on the circulation branch; a control valve assembly is arranged between the sewage discharge hole and the pressure permeable hole in the liquid channel and can open or close the liquid channel, and the end, close to the pressure permeable hole, of the control valve assembly is an incident flow end. By adopting the structure, a sample entering from the input end of the extraction column and a sample back-flushing through the first sieve plate from the buffer chamber carry scattered impurities and flow into the liquid channel through the opened pollution discharge hole, so that the impurities accumulated on the first sieve plate are thoroughly cleaned.

Description

Technical Field

[0001] This invention relates to chemical detection, specifically a chemical detection device for harmful substances in toys. Background Technology

[0002] As toys are products that children come into daily contact with, their chemical safety is of paramount importance. Toys may contain various harmful substances that can migrate into a child's body through saliva, skin contact, and other routes. Long-term exposure may cause allergies, developmental disorders, or even more serious health risks. Therefore, accurate and efficient chemical testing for harmful substances in toys is a crucial step in ensuring children's safety.

[0003] In the detection of hazardous substances in toys, especially those containing perfluorinated or polyfluorinated organic compounds (PFAS) or total fluorine, the extraction column, as a core component for purifying and enriching samples, directly affects the accuracy and reliability of the test results. However, toys have complex matrices, often containing a large number of impurities such as oils, pigments, and high molecular weight polymers. During extraction, high molecular weight impurities are easily intercepted and accumulated by the first sieve plate of the extraction column, causing blockage. With the increase in the number of tests, the blockage problem worsens, leading to increased hydraulic pressure difference between the input and output ends of the extraction column and unstable flow, thus affecting detection efficiency and accuracy.

[0004] Currently, there is a lack of efficient and convenient solutions to the problem of extraction column clogging. Common handling methods often require interrupting the detection process, such as disassembling and clearing the blockage or replacing components. These methods are not only cumbersome and time-consuming, but also require a high level of technical skill from the operators. Improper maintenance may introduce secondary contamination or damage the sealing of the device, further reducing the accuracy of the detection.

[0005] Therefore, for the detection of harmful substances such as perfluorinated or polyfluorinated organic compounds (PFAS) or total fluorine, there is an urgent need in the field for a chemical detection device for hazardous substances in toys that is easy to clean. Summary of the Invention

[0006] To overcome the existing technical problems, the present invention provides a chemical detection device for harmful substances in toys that is easy to clear blockages.

[0007] The present invention adopts the following technical solution.

[0008] A chemical detection device for hazardous substances in toys includes a liquid chromatograph body, an extraction column on the liquid chromatograph body, the extraction column including a column body, and a first sieve plate, a second sieve plate, packing material and a third sieve plate arranged sequentially in the column body along the flow direction of the sample. A drain hole is provided at the position of the column body near the flow-facing end of the first sieve plate, and a check valve structure is provided at the drain hole. A buffer chamber is formed between the first sieve plate and the second sieve plate, and an elastic sleeve is fitted on the outside of the buffer chamber. A pressure-permeable hole is provided on the column body at the position corresponding to the elastic sleeve. An outer shell is fitted around the extraction column, and a liquid channel is formed between the outer shell and the extraction column. The liquid channel is connected to a circulation branch, and a filter structure and a liquid pump are installed on the circulation branch. A control valve assembly is installed between the drain hole and the pressure vent in the liquid channel. The control valve assembly can open or close the liquid channel, and the end of it closest to the pressure vent is the flow-facing end.

[0009] As a further improvement of the present invention, the control valve assembly includes an annular valve seat disposed on the column, a valve core sleeved on the outside of the column and capable of sliding and sealingly connecting with the liquid passage, and a drive assembly drivenly connected to the valve core.

[0010] As a further improvement of the present invention, the drive assembly includes a winding structure coupled to the valve core and an elastic element connected to the valve core. The fluid passage is provided with a sliding groove that cooperates with the valve core. One end of the elastic element is connected to the sliding groove, and the elastic element keeps the valve core tending to move away from the valve seat.

[0011] As a further improvement of the present invention, the check valve structure is an elastic ring sleeved on the outside of the column. The end of the elastic ring away from the control valve assembly is the movable end, and the end closer to the control valve assembly is fixedly connected to the column. An annular mounting groove is provided on the outside of the column, and the elastic ring is disposed in the mounting groove.

[0012] As a further improvement of the present invention, a heating device is also provided on the circulation branch, and an insulation layer is provided inside the outer shell.

[0013] As a further improvement of the present invention, the outer casing includes a bottom shell and an end cap detachably connected to the bottom shell. The bottom shell is provided with an input connector for connecting to the input end of the extraction column, and the end cap is provided with an output connector for connecting to the output end of the extraction column.

[0014] As a further improvement of the present invention, the first sieve plate is provided with a deflection section, which can change the flow direction of the sample entering from the input end of the extraction column, so that it deflects from being perpendicular to the first sieve plate to being parallel to the first sieve plate.

[0015] The beneficial effects of this invention are as follows: When high molecular weight impurities accumulate on the first sieve plate and cause blockage to a certain extent, the liquid channel is quickly closed by controlling the valve assembly. After the liquid channel, which has a continuous liquid flow, is quickly closed, due to the inertia of the liquid flow, a positive pressure is generated at the flow-facing end of the control valve assembly based on the positive water hammer effect, while a negative pressure is generated at the flow-reversing end of the control valve assembly based on the negative water hammer effect. The positive pressure drives the elastic sleeve to move in the direction of reducing the volume of the buffer chamber, thereby causing the sample in the buffer chamber to backwash the first sieve plate, dispersing the impurities accumulated on the first sieve plate. At the same time, due to the negative pressure, the check valve structure is opened, and the sample entering from the extraction column input end and the sample backwashed from the buffer chamber through the first sieve plate, carrying the dispersed impurities, flow into the liquid channel through the opened drain hole. The impurities flowing into the liquid channel are filtered by the filter structure on the circulation branch, ultimately achieving thorough cleaning of the impurities accumulated on the first sieve plate. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural perspective view of the entire invention; Figure 2 This is a cross-sectional view of part of the structure of the present invention (the liquid passage is in the open state at this time). Figure 3 yes Figure 2 Enlarged view of part A; Figure 4 This is a cross-sectional view of part of the structure of the present invention (the liquid passage is in the closed state at this time). Figure 5 yes Figure 4 Enlarged view of part B.

[0018] Explanation of reference numerals in the attached figures: 1. Liquid Chromatograph Body; 2. Extraction Column; 21. Column Body; 211. Drain Hole; 212. Pressure Perforation Hole; 213. Mounting Slot; 22. First Sieve Plate; 23. Second Sieve Plate; 24. Packing Material; 25. Third Sieve Plate; 26. Check Valve Structure; 27. Buffer Chamber; 28. Elastic Sleeve; 3. Outer Shell; 31. Liquid Channel; 32. Circulation Branch; 33. Filter Structure; 34. Liquid Pump; 35. Sliding Channel; 36. Heating Device; 37. Insulation Layer; 38. Bottom Shell; 381. Input Connector; 39. End Cap; 391. Output Connector; 4. Control Valve Assembly; 41. Valve Seat; 42. Valve Core; 43. Drive Assembly; 431. Winding Structure; 432. Elastic Component; 5. Deflection Section. Detailed Implementation

[0019] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product.

[0020] It will be understood by those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings. The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Reference Figure 1-5 As can be seen, a chemical detection device for harmful substances in toys includes a liquid chromatograph body 1, an extraction column 2 on the liquid chromatograph body 1, the extraction column 2 including a column body 21, and a first sieve plate 22, a second sieve plate 23, a packing material 24 and a third sieve plate 25 arranged sequentially in the column body 21 along the flow direction of the sample. A drain hole 211 is provided at the position of the column body 21 near the flow-facing end of the first sieve plate 22, and a check valve structure 26 is provided at the drain hole 211. A buffer chamber 27 is formed between the first sieve plate 22 and the second sieve plate 23. An elastic sleeve 28 is sleeved on the outside of the buffer chamber 27. A pressure-permeable hole 212 is provided at the position of the column body 21 corresponding to the position of the elastic sleeve 28. An outer shell 3 is fitted around the extraction column 2. A liquid channel 31 is formed between the outer shell 3 and the extraction column 2. The liquid channel 31 is connected to a circulation branch 32. A filter structure 33 and a liquid pump 34 are provided on the circulation branch 32. A control valve assembly 4 is provided in the liquid channel 31 between the drain hole 211 and the pressure hole 212. The control valve assembly 4 can open or close the liquid channel 31. The end of the control valve assembly 4 that is close to the pressure hole 212 is the flow-facing end, and the end that is close to the drain hole 211 is the flow-reversing end.

[0022] The sample entering from the input end of extraction column 2 first passes through the first sieve plate 22. High molecular weight impurities in the sample are intercepted by the first sieve plate 22 and accumulate on it. When high molecular weight impurities accumulate to a certain extent on the first sieve plate 22 and cause blockage, the liquid channel 31 is quickly closed by the control valve assembly 4. At this time, after the liquid channel 31, which has a continuous liquid flow, is quickly closed, due to the inertia of the liquid flow, the upstream end of the control valve assembly 4 will generate positive pressure based on the positive water hammer effect, while the downstream end of the control valve assembly 4 will generate negative pressure based on the negative water hammer effect. Positive pressure causes the elastic sleeve 28 to move in a direction that reduces the volume of the buffer chamber 27, thereby causing the sample in the buffer chamber 27 to backwash the first sieve plate 22, flushing away the impurities accumulated on the first sieve plate 22. At the same time, negative pressure causes the check valve 26 to open the drain hole 211. The sample entering from the input end of the extraction column 2 and the sample backwashed from the buffer chamber 27 through the first sieve plate 22, carrying the dispersed impurities, flow into the liquid channel 31 through the opened drain hole 211, thereby carrying the impurities away from the column 21. The impurities flowing into the liquid channel 31 are filtered by the filter structure 33 on the circulation branch 32, ultimately achieving a thorough cleaning of the impurities accumulated on the first sieve plate 22.

[0023] Reference Figure 3 and Figure 5 The control valve assembly 4 includes an annular valve seat 41 disposed on the column 21, a valve core 42 sleeved on the outside of the column 21 and capable of sliding and sealingly connecting with the liquid passage 31, and a drive assembly 43 drivenly connected to the valve core 42.

[0024] By driving the valve core 42 to slide on the liquid channel 31 and abut against the valve seat 41 through the drive component 43, a sealed connection between the valve core 42 and the liquid channel 31 can be achieved, thereby quickly blocking the flow of liquid in the liquid channel 31.

[0025] Reference Figure 3 and Figure 5 The drive assembly 43 includes a winding structure 431 coupled to the valve core 42 and an elastic element 432 connected to the valve core 42. The fluid passage 31 is provided with a sliding groove 35 that cooperates with the valve core 42. One end of the elastic element 432 is connected to the sliding groove 35. The elastic element 432 keeps the valve core 42 tending to move away from the valve seat 41.

[0026] The valve core 42 is magnetic and can be driven to abut against the valve seat 41 by the winding structure 431, or it can be driven to detach from the valve seat 41. Of course, the present invention preferably uses the elastic element 432 to drive the valve core 42 away from the valve seat 41, thereby reducing the control frequency of the winding structure 431.

[0027] Reference Figure 3 and Figure 5The non-return structure 26 is an elastic ring sleeved on the outside of the column 21. The end of the elastic ring away from the control valve assembly 4 is the movable end, and the end closer to the control valve assembly 4 is fixedly connected to the column 21. An annular mounting groove 213 is provided on the outside of the column 21, and the elastic ring is located in the mounting groove 213.

[0028] When the liquid channel 31 is quickly closed, the sample in the buffer chamber 27 will backwash the first sieve plate 22, that is, in Figure 5 As shown, the samples in buffer chamber 27 are rinsed from bottom to top. When the elastic ring is opened under negative pressure, its movable end faces... Figure 5 The upper right side corresponds to the upward flow direction of the sample in the buffer chamber 27, allowing the dispersed impurities to flow out smoothly through the drain hole 211 opened by the elastic ring. Impurities flowing into the liquid channel 31 are filtered by the filter structure 33 on the circulation branch 32. However, if the end near the control valve assembly 4 is set as the movable end, when the elastic ring is opened under negative pressure, its movable end will face downward to the right, thus blocking the sample from flowing out of the buffer chamber 27.

[0029] Reference Figure 2 and Figure 4 The circulation branch 32 is also equipped with a heating device 36, and the outer shell 3 is equipped with an insulation layer 37.

[0030] During extraction, the liquid in the circulation branch 32 is heated by the heating device 36. The heated liquid flows into the liquid channel 31 under the action of the liquid pump 34, thereby realizing the water bath heating of the column 21. The heating can accelerate the extraction of toxic and harmful substances, allowing the sample to be extracted at a suitable temperature and improving the extraction efficiency.

[0031] Reference Figure 2 and Figure 4 The outer casing 3 includes a bottom casing 38 and an end cap 39 detachably connected to the bottom casing 38. The bottom casing 38 is provided with an input connector 381 for connecting to the input end of the extraction column 2, and the end cap 39 is provided with an output connector 391 for connecting to the output end of the extraction column 2.

[0032] Reference Figure 3 and Figure 5 The first sieve plate 22 is provided with a deflection section 5, which can change the flow direction of the sample entering from the input end of the extraction column 2, so that it deflects from being perpendicular to the first sieve plate 22 to being parallel to the first sieve plate 22.

[0033] By shaping the flow direction of the sample through the deflection section 5, the flow direction of the sample is deflected from perpendicular to the first sieve plate 22 to parallel to the first sieve plate 22. This allows the sample to flow out evenly from all sides of the deflection section 5, slowing down the flow rate and making both the flow rate and direction more uniform, which is more conducive to the extraction of the sample and improves the extraction efficiency.

[0034] Complete explanation of its working principle: Under normal operating conditions, the heating device 36 heats the liquid in the circulation branch 32. The heated liquid then flows into the liquid channel 31 under the action of the liquid pump 34, thereby achieving water bath heating of the column 21 and accelerating the extraction of toxic and harmful substances. The sample flows into the column 21 from the input end of the extraction column through the input connector 381 and along... Figure 3 The flow direction shown is contacted with the deflection section 5. Under the action of the deflection section 5, the flow direction of the sample is deflected from perpendicular to the first sieve plate 22 to parallel to the first sieve plate 22. This allows the sample to flow out evenly from all sides of the deflection section 5, slowing down the flow rate and making both the flow rate and direction more uniform, which is more conducive to the extraction of the sample and improves the extraction efficiency. At the same time, due to the hydraulic pressure in the liquid channel acting on the elastic ring, the movable end of the elastic ring is pressed tightly against the outer wall of the column, thereby closing the outlet hole. Thus, the sample flowing parallel to the first sieve plate 22 passes through the first sieve plate 22, and then flows sequentially through the second sieve plate 23, the packing 24, and the third sieve plate 25. During this process, high molecular weight impurities in the sample are intercepted when passing through the first sieve plate 22, while low molecular weight analytes in the sample interact with the packing 24 to achieve extraction.

[0035] As the number of tests increases, more and more impurities accumulate on the first sieve plate 22, eventually clogging it. Figure 2 Hydraulic sensors are installed at both the input connector 381 and the output connector 391. As the blockage of the first screen plate 22 becomes more severe, the pressure difference detected by the two hydraulic sensors will increase. When it reaches a certain level, it indicates that the first screen plate 22 is blocked. At this time, the winding structure 431 drives the valve core 42 to quickly abut against the valve seat 41. The valve core 42 and the valve seat 41 work together to quickly close the liquid passage 31. After the liquid passage 31, which has a continuous flow of liquid, is quickly closed, due to the inertia of the liquid flow, the liquid passage 31 will generate positive pressure at the flow-facing end of the valve core 42 based on the positive water hammer effect, while the liquid passage 31 will generate negative pressure at the flow-reversing end of the valve core 42 based on the negative water hammer effect. Positive pressure causes the elastic sleeve 28 to move in a direction that reduces the volume of the buffer chamber 27, thereby causing the sample in the buffer chamber 27 to backwash the first sieve plate 22, flushing away the impurities accumulated on the first sieve plate 22. At the same time, negative pressure causes the check valve 26 to open the drain hole 211. The sample flowing parallel to the first sieve plate 22 under the action of the deflection section 5, along with the sample backwashed from the buffer chamber 27 through the first sieve plate 22, carries the dispersed impurities into the liquid channel 31 through the opened drain hole 211, thereby carrying the impurities away from the column 21. The impurities flowing into the liquid channel 31 are filtered by the filter structure 33 on the circulation branch 32, ultimately achieving a thorough cleaning of the impurities accumulated on the first sieve plate 22.

[0036] In this embodiment, the liquid in the circulation branch and the liquid channel is pure water.

[0037] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A chemical detection device for harmful substances in toys, comprising a liquid chromatograph body, wherein the liquid chromatograph body is provided with an extraction column, characterized in that, The extraction column includes a column body, and a first sieve plate, a second sieve plate, a packing material, and a third sieve plate arranged sequentially in the column body along the flow direction of the sample. A drain hole is provided at the position of the column body near the flow-facing end of the first sieve plate, and a check valve structure is provided at the drain hole. A buffer chamber is formed between the first sieve plate and the second sieve plate, and an elastic sleeve is fitted on the outside of the buffer chamber. A pressure-permeable hole is provided on the column body at the position corresponding to the elastic sleeve. The extraction column is fitted with a shell, and a liquid channel is formed between the shell and the extraction column. The liquid channel is connected to a circulation branch, and a filter structure and a liquid pump are provided on the circulation branch. A control valve assembly is provided in the liquid channel between the drain hole and the pressure-permeable hole. The control valve assembly can open or close the liquid channel, and the end of it near the pressure-permeable hole is the flow-facing end.

2. The chemical detection device for harmful substances in toys according to claim 1, characterized in that, The control valve assembly includes an annular valve seat disposed on the column, a valve core sleeved on the outside of the column and capable of sliding and sealingly connecting with the liquid passage, and a drive assembly drivenly connected to the valve core.

3. The chemical detection device for harmful substances in toys according to claim 2, characterized in that, The drive assembly includes a winding structure coupled to the valve core and an elastic element connected to the valve core. The fluid passage is provided with a sliding groove that cooperates with the valve core. One end of the elastic element is connected to the sliding groove, and the elastic element causes the valve core to tend to move away from the valve seat.

4. The chemical detection device for harmful substances in toys according to claim 1, characterized in that, The check valve structure is an elastic ring sleeved on the outside of the column. The end of the elastic ring away from the control valve assembly is a movable end, and the end closer to the control valve assembly is fixedly connected to the column. An annular mounting groove is provided on the outside of the column, and the elastic ring is disposed in the mounting groove.

5. The chemical detection device for harmful substances in toys according to claim 1, characterized in that, A heating device is also provided on the circulation branch, and an insulation layer is provided inside the outer shell.

6. The chemical detection device for harmful substances in toys according to claim 1, characterized in that, The housing includes a bottom shell and an end cap detachably connected to the bottom shell. The bottom shell is provided with an input connector for connecting to the input end of the extraction column, and the end cap is provided with an output connector for connecting to the output end of the extraction column.

7. The chemical detection device for harmful substances in toys according to claim 1, characterized in that, The first sieve plate is provided with a deflection section, which can change the flow direction of the sample entering from the input end of the extraction column, so that it deflects from being perpendicular to the first sieve plate to being parallel to the first sieve plate.

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