Multimeter-based dust-free cloth alcohol soaking detection device and method
By using a multimeter-based detection device to determine the degree of alcohol wetting of a cleanroom cloth by measuring changes in resistance, the problems of low detection accuracy and high maintenance workload in existing technologies are solved. This achieves high-precision, low-error-rate alcohol wetting detection, meeting the real-time control requirements of automated equipment.
Patent Information
- Application Number
- CN202511645263.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-02-17
AI Technical Summary
In existing technologies, color sensors and fiber optic sensors are easily affected by ambient light and surface flatness when detecting the alcohol immersion state of cleanroom cloths, resulting in low detection accuracy and a large amount of maintenance work, which cannot meet the needs of rapid production and high-quality control.
The device employs a multimeter-based testing mechanism. It detects the conductive path formed when a lint-free cloth comes into contact with alcohol and uses the resistance value displayed by the multimeter to determine the degree of alcohol wetting. The device includes a testing frame, wiping head, test block, and wiring holes. It has a simple structure and is not affected by the environment or surface flatness.
It achieves high-precision, low-error-rate alcohol immersion detection, with an error rate of ≤0.5% and a response time of ≤0.1s, meeting the real-time control requirements of automated equipment and reducing maintenance workload.
Smart Images
Figure CN121540769A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of electronic product cleaning auxiliary devices, specifically relating to a device and method for detecting alcohol immersion in a lint-free cloth based on a multimeter. Background Technology
[0002] With the rapid pace of technological advancements in electronic products and increasingly stringent consumer demands for product quality, the cleaning and testing processes in production are becoming increasingly crucial. In equipment cleaning, the precise control of the alcohol saturation level of lint-free cloths, a commonly used cleaning tool, directly impacts cleaning effectiveness. In 3C product manufacturing, cleaning precision components such as mobile phone screens and computer motherboards is critical. Insufficient alcohol saturation on the lint-free cloth will fail to effectively remove surface stains, potentially leaving impurities that affect product performance and appearance. Conversely, over-saturation may allow excess alcohol to seep into the equipment, damaging electronic components.
[0003] Currently, the industry mainly relies on color sensors and light sensors to detect the alcohol immersion status of cleanroom wipes. Among them, the color sensor detection technology works by utilizing the color characteristics of the light reflected from the surface of the cleanroom wipe after it is soaked in alcohol (e.g., a white cleanroom wipe becomes translucent after being soaked in alcohol, and the color depth increases). The color sensor collects color parameters (such as RGB values) and compares them with a preset threshold to determine the immersion status. However, color sensors are easily affected by changes in ambient light intensity and color temperature. For example, when the workshop lighting is switched or natural light shines in, misjudgments are likely to occur. Fiber optic sensor detection technology works by emitting a specific wavelength beam of light onto the surface of a cleanroom cloth via an optical fiber transmitter, and collecting the reflected light at the optical fiber receiver. When the cleanroom cloth is soaked in alcohol, the surface reflectivity changes, leading to an increase in the amount of reflected light. The sensor's return value is then compared with a preset threshold to determine the wetting status. However, fiber optic sensors are sensitive to the flatness of the cleanroom cloth surface. Wrinkles or warped fibers can cause fluctuations in the amount of reflected light, reducing detection accuracy. Furthermore, the surface of the optical sensor is easily contaminated with dust and alcohol mist, requiring regular cleaning and calibration; otherwise, detection drift can occur, increasing equipment maintenance workload. Therefore, the current method of detecting the alcohol wetting level of cleanroom cloth using fiber optic and color sensors is insufficient to meet the demands of rapid production and high-quality control, and further improvements are urgently needed. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a device and method for detecting alcohol immersion in a cleanroom cloth based on a multimeter.
[0005] The present invention adopts the following technical solution: A multimeter-based device for detecting alcohol immersion in a cleanroom cloth includes a testing frame, a wiping head mounted on the testing frame, a cleanroom cloth wrapped around the lower end of the wiping head, an outlet hole at the bottom of the wiping head opposite the cleanroom cloth for alcohol to flow out, two test blocks positioned opposite each other on both sides of the wiping head, two insulating pads respectively positioned between the two test blocks and the sides of the wiping head, and two wiring holes respectively positioned on the two test blocks. The lower end of the test blocks remains in contact with the cleanroom cloth at all times. The testing frame is provided with an inlet channel communicating with the outlet hole for alcohol to enter. During the alcohol immersion test of the cleanroom cloth, the two test probes of the multimeter are connected to the two wiring holes respectively, and the degree of alcohol immersion of the cleanroom cloth is determined by the resistance value displayed on the multimeter.
[0006] Preferably, the test block includes a test block body connected to the wiping head and two positioning parts disposed opposite to each other on the outside of the test block body. The lint-free cloth is pulled between the two positioning parts, extends from the lower end of the test block body, passes through the lower end face of the wiping head, and then to the lower end of the other test block.
[0007] Preferably, the lower outer side of the test block body is provided with a guide surface that is inclined in the direction close to the wiping head, and the lint-free cloth is pulled and adhered to the guide surface.
[0008] Preferably, the lower end of the test block body is provided with an arc-shaped guide portion that is inclined towards the wiping head, and the guide surface extends downward from the middle section of the test block body to the arc-shaped guide portion.
[0009] Preferably, the wiping head includes a mounting block connected to the testing frame, a wiping part extending downward from the bottom of the mounting block, and two guide rollers disposed opposite each other on both sides of the mounting block. The lower end of the wiping part is chamfered, and the two testing blocks are disposed opposite each other on both sides of the wiping part. The guide rollers are in contact with the lint-free cloth that is pulled to the wiping head.
[0010] Preferably, the liquid outlet extends downward from the top surface of the mounting block to the bottom of the wiping section. The top surface of the mounting block forms a liquid receiving groove surrounding the liquid outlet and a sealing groove surrounding the liquid receiving groove. The liquid inlet channel includes a horizontal section arranged laterally in the detection frame and a vertical section extending downward in communication with the horizontal section. The lower end of the vertical section is opposite to the liquid receiving groove.
[0011] Preferably, it also includes two locking components that fix the two test blocks to the wiping head respectively. The locking components include a first locking hole provided on the wiping head, a second locking hole provided on the insulating pad opposite to the first locking hole, a third locking hole provided on the test block opposite to the second locking hole, and a locking bolt that passes through the third locking hole, the second locking hole and the first locking hole in sequence and is threadedly connected.
[0012] A method for detecting alcohol immersion in a cleanroom cloth based on a multimeter, characterized in that: the detection device described above is used, and specifically includes the following steps: Initial state test: When the cleanroom cloth is not wetted by alcohol, because the cleanroom cloth is an insulator, the two test blocks are in an open circuit state, and the multimeter displays "overload"; Wet state detection: When alcohol is applied to the cleanroom cloth through the outlet, the alcohol diffuses between the cleanroom cloth fibers and covers the contact area of the two test blocks, forming a conductive path; at this time, the resistance value detected by the multimeter changes from "overload" to a readable value, triggering the detection signal. Status Judgment: The wetness of the cleanroom cloth is determined by the change in the resistance value of the multimeter. When the resistance value is between 1×10⁻⁶, the wetness is determined. 7 -9×10 8 When the concentration is Ω, it is determined that the cleanroom cloth contains alcohol. Specific scenarios are as follows: (1) When the resistance value is between 3×10 8 -5×10 8 At Ω, the alcohol-soaked cloth is at its optimal level and can be used for wiping. (2) When the resistance value is between 1×10 7 -3×10 8 When the alcohol level is between Ω, the cleanroom cloth is over-wetted, and at this point, the cleanroom cloth is a defective product and cannot be used for wiping. (3) When the resistance value is between 5×10 8 -9×10 8 When the alcohol concentration is between Ω, the cleanroom cloth is not sufficiently wetted with alcohol. In this case, the cleanroom cloth is a defective product and cannot be used for wiping.
[0013] Preferably, the cleanroom cloth is a polyester fiber cleanroom cloth or a microfiber cleanroom cloth, which is an insulator when not wet, with a resistance value ≥1×10⁻⁶. 9 Ω.
[0014] Preferably, the test block is made of conductive metal.
[0015] As can be seen from the above description of the present invention, compared with the prior art, the beneficial effects of the present invention are as follows: The detection device defined by the present invention has a simple structure and is easy to maintain, without precision optical components and without the need for complex calibration mechanisms; moreover, the test block is wear-resistant and pollution-resistant, and daily maintenance only requires periodic checks of wire connections and contact pressure, reducing maintenance workload; wherein, the detection is achieved by utilizing the conductive properties of alcohol, and is not affected by the environment or the flatness of the cleanroom cloth surface. Even if the cleanroom cloth has wrinkles or uneven fiber distribution, as long as the alcohol forms a path, stable detection can be achieved with an error rate ≤0.5%; at the same time, the change in resistance value after alcohol wetting is completed instantaneously, and the multimeter detection response time is ≤0.1s, meeting the real-time control requirements of automated equipment. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the detection device. Figure 2 This is a cross-sectional view of the detection device. Figure 3 This is a schematic diagram of the structure of the wiping head and the test block; Figure 4 for Figure 3 A schematic diagram of the decomposition process; Figure 5 This is a schematic diagram of the test block structure; In the diagram, 1. Testing frame; 2. Wiping head; 3. Dust-free cloth; 4. Liquid outlet; 5. Test block; 6. Insulating pad; 7. Wiring hole; 8. Locking component; 11. Liquid inlet channel; 12. Horizontal section; 13. Vertical section; 14. Connector; 21. Mounting block; 22. Wiping part; 23. Guide roller; 24. Liquid receiving tank; 25. Sealing groove; 51. Test block body; 52. Positioning part; 53. Guide surface; 54. Arc-shaped guide part; 81. First locking hole; 82. Second locking hole; 83. Third locking hole. Detailed Implementation
[0017] The present invention will be further described below through specific embodiments.
[0018] Reference Figures 1 to 5 As shown, a lint-free cloth alcohol wetting detection device based on a multimeter includes a detection frame 1, a wiping head 2 mounted on the detection frame 1, a lint-free cloth 3 wrapped around the lower end face of the wiping head 2, an outlet hole 4 at the bottom of the wiping head 2 opposite to the lint-free cloth 3 for alcohol to flow out, two test blocks 5 opposite to each other on both sides of the wiping head 2, two insulating pads 6 respectively disposed between the two test blocks 5 and the sides of the wiping head 2, two wiring holes 7 respectively disposed on the two test blocks 5, and a device for fixing the two test blocks 5 to the lint-free cloth. The wiping head 2 has two locking parts 8. The lower end face of the test block 5 is always in contact with the cleanroom cloth 3. The test frame 1 is provided with a liquid inlet channel 11 that communicates with the liquid outlet 4 to allow alcohol to enter. When the cleanroom cloth 3 is tested for alcohol immersion, the two test probes of the multimeter are connected to the two wiring holes 7 respectively. The degree of alcohol immersion of the cleanroom cloth 3 is determined by the resistance value displayed on the multimeter. Specifically, the cleanroom cloth 3 is a polyester fiber cleanroom cloth or a microfiber cleanroom cloth. When it is not wet, it is an insulator with a resistance value ≥1×10. 9 Ω; after being soaked in alcohol, the overall conductivity is significantly improved due to the conductivity of alcohol (containing trace amounts of electrolyte); furthermore, the test probes are electrically connected to the opposite wiring holes 7 through shielded wires to detect the resistance value between the two wiring holes 7 in real time.
[0019] The wiping head 2 includes a mounting block 21 detachably connected to the testing frame 1, a wiping section 22 extending downward from the bottom of the mounting block 21, and two guide rollers 23 opposite to each other on both sides of the mounting block 21. The lower end of the wiping section 22 is chamfered, and the two test blocks 5 are opposite to each other on both sides of the wiping section 22. The guide rollers 23 contact the lint-free cloth 3 pulled to the wiping head 2. Specifically, the liquid outlet 4 extends downward from the top surface of the mounting block 21 to the bottom of the wiping section 22. The top surface of the mounting block 21 forms a liquid receiving groove 24 surrounding the liquid outlet 4 and a sealing groove 25 surrounding the liquid receiving groove 24. The liquid inlet channel 11 includes a horizontal section 12 transversely arranged in the testing frame 1 and a vertical section 13 extending downward in communication with the horizontal section 12. The horizontal section 12 can be connected to an alcohol supply device through a connector 14, and the lower end of the vertical section 13 is opposite to the liquid receiving groove 24. In use, a sealing ring is installed in the sealing groove 25 to ensure the sealing between the liquid inlet channel 11 and the liquid outlet 4.
[0020] Test block 5, made of conductive metal such as copper or stainless steel, includes a test block body 51 connected to the wiping head 2 and two positioning parts 52 disposed opposite to each other on the outer side of the test block body 51. A lint-free cloth 3 is pulled between the two positioning parts 52, extending from the lower end of the test block body 51, passing over the lower end face of the wiping head 2, and then to the lower end of another test block. Specifically, a guide surface 53 inclined towards the wiping head 2 is provided on the lower outer side of the test block body 51, and the lint-free cloth 3 is pulled to fit against the guide surface 53. Furthermore, an arc-shaped guide part 54 inclined towards the wiping head 2 is provided at the lower end of the test block body 51, and the guide surface 53 extends downward from the middle section of the test block body 51 to the arc-shaped guide part 54. Through the cooperation of the guide surface 53 and the arc-shaped guide part 54, the lint-free cloth 3 is ensured to always maintain contact with the lower outer side of the test block 5, guaranteeing the accuracy of the test results.
[0021] The locking component 8 includes a first locking hole 81 on the wiping head 2, a second locking hole 82 on the insulating pad 6 opposite to the first locking hole 81, a third locking hole 83 on the test block 5 opposite to the second locking hole 82, and a locking bolt that passes through the third locking hole 83, the second locking hole 82 and the first locking hole 81 in sequence and is threadedly connected. The locking component 8 allows the test block 5 to be detachably mounted on one side of the wiping head 2, making it easy to replace when the test block 5 is worn.
[0022] The method for detecting alcohol immersion in a cleanroom cloth based on the above-mentioned device specifically includes the following steps: Initial state test: When the cleanroom cloth 3 is not wetted by alcohol, because the cleanroom cloth 3 is an insulator, the two test blocks 5 are in an open circuit state, and the multimeter displays "overload". Wet state detection: When alcohol is applied to the cleanroom cloth 3 through the outlet hole 4, the alcohol diffuses between the fibers of the cleanroom cloth 3 and covers the contact area of the two test blocks 5, forming a conductive path; at this time, the resistance value detected by the multimeter changes from "overload" to a readable value, triggering the detection signal. Status Judgment: The wetness status of the cleanroom cloth 3 is determined by the change in the resistance value of the multimeter. When the resistance value is between 1×10⁻⁶... 7 -9×10 8 When Ω is reached, it is determined that the cleanroom cloth 3 contains alcohol, and the specific situations are as follows: (1) When the resistance value is between 3×10 8 -5×10 8 At Ω, the alcohol-soaked cloth 3 is at its optimal level and can be used for wiping. (2) When the resistance value is between 1×10 7 -3×10 8 When the alcohol level is between Ω, the alcohol saturation of the cleanroom cloth 3 is excessive. At this point, the cleanroom cloth 3 is a defective product and cannot be used for wiping. (3) When the resistance value is between 5×10 8 -9×10 8 When the alcohol content is between Ω, the alcohol saturation of the cleanroom cloth 3 is insufficient. In this case, the cleanroom cloth 3 is a defective product and cannot be used for wiping.
[0023] The detection device defined in this invention has a simple and easy-to-maintain structure, requires no precision optical components, and does not require a complex calibration mechanism. Furthermore, the test block 5 is wear-resistant and pollution-resistant, and daily maintenance only requires periodic checks of wire connections and contact pressure, reducing maintenance workload. The detection is achieved by utilizing the conductive properties of alcohol, and is not affected by the environment or the flatness of the cleanroom cloth 3 surface. Even if the cleanroom cloth 3 has wrinkles or uneven fiber distribution, as long as the alcohol forms a path, stable detection is possible with an error rate of ≤0.5%. At the same time, the change in resistance value after alcohol wetting is instantaneous, and the multimeter detection response time is ≤0.1s, meeting the real-time control requirements of automated equipment.
[0024] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the specification of the present invention should still fall within the scope of the patent of the present invention.
Claims
1. A dustless cloth alcohol wetting detection device based on a multimeter, characterized in that: The detection device comprises a detection frame, a wiping head arranged on the detection frame, a dust-free cloth pulled around the lower end surface of the wiping head, a liquid outlet hole arranged at the bottom of the wiping head and opposite to the dust-free cloth for alcohol to flow out, two test blocks arranged opposite to the two sides of the wiping head, two insulating pads arranged between the two test blocks and the side surfaces of the wiping head, and two wiring holes arranged on the two test blocks, respectively. The lower end surface of the test block is always in contact with the dust-free cloth. The detection frame is provided with a liquid inlet channel in communication with the liquid outlet hole for alcohol to enter. When the dust-free cloth is soaked with alcohol, the two test pens of the multimeter are connected to the two wiring holes, and the resistance value displayed on the multimeter is used to judge the soaking degree of the dust-free cloth.
2. A dust-free cloth alcohol wetting detection device based on a multimeter according to claim 1, characterized in that: The test block comprises a test block body connected with the wiping head and two positioning portions arranged opposite to the outer side of the test block body. The dust-free cloth is pulled between the two positioning portions, extends from the lower end of the test block body to the lower end surface of the wiping head, and then to the lower end of the other test block.
3. A dust-free cloth alcohol wetting detection device based on a multimeter according to claim 2, characterized in that: The lower side of the test block body is provided with a guide surface inclined in the direction close to the wiping head. The dust-free cloth is pulled and attached to the guide surface.
4. The dust-free cloth alcohol wetting detection device based on a multimeter according to claim 2, characterized in that: The lower end of the test block body is provided with an arc-shaped guide portion inclined in the direction close to the wiping head. The guide surface extends downward from the middle section of the test block body to the arc-shaped guide portion.
5. The dust-free cloth alcohol wetting detection device based on a multimeter according to claim 1, characterized in that: The wiping head comprises a mounting block connected with the detection frame, a wiping portion extending downward from the bottom of the mounting block, and two guide rollers arranged opposite to the two sides of the mounting block. The lower end of the wiping portion is arranged in a chamfered manner. The two test blocks are arranged opposite to the two sides of the wiping portion. The guide rollers are in contact with the dust-free cloth pulled to the wiping head.
6. A dust-free cloth alcohol wetting detection device based on a multimeter according to claim 5, characterized in that: The liquid outlet hole extends downward from the top surface of the mounting block to the bottom of the wiping portion. The top surface of the mounting block is formed with a liquid receiving groove arranged around the liquid outlet hole and a sealing groove arranged around the liquid receiving groove. The liquid inlet channel comprises a horizontal section arranged transversely in the detection frame and a vertical section in communication with the horizontal section and extending downward. The lower end of the vertical section is opposite to the liquid receiving groove.
7. The dust-free cloth alcohol wetting detection device based on a multimeter according to claim 1, characterized in that: The detection device further comprises two locking members for fixing the two test blocks on the wiping head, respectively. The locking member comprises a first locking hole arranged on the wiping head, a second locking hole arranged on the insulating pad and opposite to the first locking hole, a third locking hole arranged on the test block and opposite to the second locking hole, and a locking bolt sequentially threaded through the third locking hole, the second locking hole and the first locking hole.
8. A method for detecting the wetness of a dust cloth based on a multimeter, characterized in that: The detection device is used to perform the following steps: Initial state detection: when the dust-free cloth is not soaked with alcohol, the dust-free cloth is an insulator, the two test blocks are in an open circuit state, and the multimeter displays "overload"; Soaking state detection: when alcohol acts on the dust-free cloth through the liquid outlet hole, alcohol diffuses between the fibers of the dust-free cloth and covers the contact area of the two test blocks, forming a conductive path. At this time, the resistance value detected by the multimeter changes from "overload" to a readable value, triggering a detection signal; State judgment: according to the change of resistance value of the multimeter, the state of the dust-free cloth soaked is judged, when the resistance value is between 1×10 7 -9×10 8 Ω, it is judged that the dust-free cloth contains alcohol, and the specific circumstances are as follows: (1) When the resistance value is between 3 x 10 8 -5 x 10 8 Ω, the alcohol wetting degree of the lint is optimal, and the lint can be used for wiping at this time; (2) When the resistance value is between 1 x 10 7 -3 x 10 8 Ω, the alcohol wetting degree of the lint-free cloth is a transition wetting, at this time, the lint-free cloth is a poor product and cannot be used for wiping; (3) When the resistance value is between 5 x 10 8 -9 x 10 8 Ω, the alcohol wetting degree of the lint-free cloth is insufficient, at this time, the lint-free cloth is a defective product and cannot be used for wiping.
9. A method of detecting the wetness of a duster cloth based on a multimeter according to claim 8, characterized in that: The dustless cloth is polyester fiber dustless cloth or superfine fiber dustless cloth, which is an insulator when not wetted, with an electric resistance value ≥ 1×10 9 Ω.
10. A method of detecting the wetness of a duster based on a multimeter according to claim 8, characterized in that: The test block is made of a conductive metal.