Intelligent sensing system for detecting air tightness of bottle body

Abstract

The invention relates to the technical field of intelligent sensing, in particular to an intelligent sensing system for detecting the airtightness of a bottle body, and the system comprises a data collection module which comprises an image collector, a pressure sensor and a speed sensor; the air tightness detection module comprises a mode determination unit used for determining an air injection mode, a positioning unit used for determining whether the position of the air injection port is qualified or not according to the centering deviation, and an air tightness detection unit used for detecting the air tightness under the condition that the position of the air injection port is determined to be unqualified; the bottle body detection unit is used for adjusting the gas injection position of a gas injection port or adjusting the pulse frequency of a motor according to the interval standard deviation of a plurality of bottle mouths, and the gas injection correction unit is used for determining whether the bottle mouths are completely sealed or not based on the rising speed of the pressure of the bottle bodies in the gas injection process so as to increase the contact pressure under the condition that the bottle mouths are not completely sealed. And an air tightness determination unit for determining whether the air tightness of the bottle body is qualified based on the descending rate of the bottle body pressure. According to the invention, the misjudgment rate of airtightness detection is reduced.

Description

Technical Field

[0001] This invention relates to the field of intelligent sensing technology, and in particular to an intelligent sensing system for detecting the airtightness of bottles. Background Technology

[0002] In the field of bottle airtightness testing, traditional testing systems typically rely on a single pressure sensor to monitor pressure changes inside the bottle to determine its seal. However, their accuracy is highly dependent on the contact state between the bottle neck and the gasket at the injection port. In actual production, due to bottle manufacturing tolerances, such as deviations in bottle neck roundness, verticality deviations, deformation, or uneven compression caused by gasket aging (e.g., decreased elasticity), problems such as eccentricity, poor local contact, or excessive gaps often occur between the bottle neck and the gasket. These contact anomalies directly interfere with the accuracy of the pressure signal—for example, when poor contact causes gas to leak from the gap, the rate of pressure rise or pressure drop during the holding phase may be misjudged as "bottle leakage"; conversely, when the gasket is locally loose due to uneven contact, even if the bottle is actually well-sealed, pressure changes may exhibit abnormal fluctuations. Traditional systems, lacking real-time monitoring capabilities of the contact state, struggle to distinguish between "true leaks" and "false leaks caused by poor contact," resulting in a high rate of false positives.

[0003] Chinese Patent Publication No. CN202510259491.X discloses an airtightness testing device, relating to the field of airtightness testing technology. This airtightness testing device includes a movable support frame, an air pump, multiple testing components, and a distribution pipe. The air pump is mounted on the movable support frame, and the multiple testing components are spaced apart on the movable support frame. Each testing component includes a connector, a pressure sensing element, a first connecting pipe, a closing valve, and a second connecting pipe connected in sequence. The connector is used to connect to the part to be tested. The distribution pipe connects the second connecting pipe to the air pump. The distribution pipe can distribute the airflow output by the air pump to each testing component, allowing multiple testing components to simultaneously perform airtightness testing on multiple cold plates, thereby improving testing efficiency. Furthermore, the closing valves in each testing component can control the on / off connection between each testing channel and the distribution pipe, avoiding mutual interference during testing.

[0004] The existing technology also has the following problems: When testing the air tightness of plastic bottles, the existing technology usually relies on a single pressure sensor to monitor the change of pressure inside the bottle to determine the air tightness of the bottle. The lack of monitoring of whether the sealing gasket between the bottle mouth and the air inlet is good leads to a high misjudgment rate of the air tightness test results. Summary of the Invention

[0005] To address this issue, the present invention provides an intelligent sensing system for detecting the airtightness of bottles, thereby overcoming the problem of high misjudgment rate of airtightness detection results caused by the lack of monitoring of the sealing performance of the bottle mouth and the gas filling port in the prior art.

[0006] To achieve the above objectives, the present invention provides an intelligent sensing system for detecting the airtightness of bottles, comprising: The data acquisition module includes an image acquisition device for acquiring several images of the bottle during the airtightness test, and a pressure sensor for acquiring the pressure of the bottle. An airtightness testing module, connected to the data acquisition module, includes, The mode determination unit is used to determine tilt characterization parameters based on several images of the bottle body, so as to determine the gas injection mode as either low-pressure gas injection followed by high-pressure gas injection or constant-pressure gas injection according to the tilt characterization parameters. The positioning unit is used to determine the alignment deviation between the gas injection port and the bottle mouth based on several images, and to determine whether the position of the gas injection port is qualified based on the comparison result of the alignment deviation and the first preset deviation. The bottle detection unit is used to determine the spacing of several bottle openings based on the comparison result of the coaxiality deviation between the bottle opening and the bottle body and the second preset deviation when the position of the gas injection port is determined to be unqualified, so as to adjust the gas injection position of the gas injection port or adjust the pulse frequency of the motor according to the standard deviation of the spacing of several bottle openings. The gas injection correction unit is used to determine whether the bottle opening is completely sealed based on the rate of increase of the bottle pressure during the gas injection process, so as to increase the contact pressure between the sealing gasket of the gas injection port and the bottle opening if it is determined that it is not completely sealed. An airtightness determination unit is used to determine whether the airtightness of the bottle is qualified based on the rate of decrease of the bottle pressure during the pressure holding process.

[0007] Furthermore, the tilt characterization parameters are determined based on a first view and a second view of the bottle body; The acquisition directions of the first view and the second view are at a 45° angle.

[0008] Furthermore, the mode determination unit determines the gas injection mode as low-pressure gas injection followed by high-pressure gas injection based on the comparison result of the tilt characterization parameter being less than the preset tilt characterization parameter; Based on the comparison result that the tilt characterization parameter is greater than or equal to the preset tilt characterization parameter, the gas injection mode is determined to be constant pressure gas injection.

[0009] Furthermore, in the corresponding gas injection mode, the positioning unit determines that the position of the gas injection port is unqualified based on the comparison result that the centering deviation is greater than the first preset deviation; The position of the gas injection port is determined to be qualified based on the comparison result that the centering deviation is less than or equal to the first preset deviation.

[0010] Furthermore, when the position of the gas injection port is determined to be unqualified, the bottle detection unit determines the spacing of several bottle ports to determine the spacing standard deviation based on the comparison result that the coaxiality deviation between the bottle port and the bottle body is less than or equal to a second preset deviation.

[0011] Furthermore, the bottle detection unit determines the injection position of the injection port based on the comparison result that the standard deviation of the spacing is less than or equal to the preset standard deviation.

[0012] Furthermore, the bottle detection unit, under the condition of determining the gas injection position of the gas injection port, determines the moving distance of the gas injection position based on the average of several alignment deviations between the bottle mouth and the gas injection port.

[0013] Furthermore, the gas injection correction unit determines that the bottle opening is not completely sealed based on a comparison result where the rising rate is less than or equal to a first preset rate.

[0014] Furthermore, when the gas injection correction unit determines that the bottle opening is not completely sealed, it sets a number of pressure adjustment coefficients according to the first rate difference between the first preset rate and the rising rate to increase the contact pressure.

[0015] Furthermore, the airtightness determination unit determines that the airtightness of the bottle is unqualified based on the comparison result that the descent rate is greater than the second preset rate; The airtightness of the bottle is determined to be qualified based on the comparison result that the descent rate is less than or equal to the second preset rate.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: When testing the air tightness of plastic bottles, the present invention first determines the injection mode by the tilt characteristic parameter of the bottle body. If the tilt characteristic parameter of the bottle body is unqualified, a low-pressure followed by a high-pressure injection mode is adopted. The unqualified tilt characteristic parameter of the bottle body will cause the bottle mouth to tilt. When the sealing gasket of the injection port contacts the bottle mouth, it is easy for one side to be over-compressed and the other side not to be fully fitted, forming a local gap. The sealing gasket has a certain elasticity and can compensate for the uneven contact caused by the tilt of the bottle mouth through creep deformation or elastic expansion. The low-pressure injection stage allows the sealing gasket to initially adapt to the tilt of the bottle mouth, while the high-pressure injection further pushes the sealing gasket to fill the uncontacted side, using the material deformation under high pressure to reduce or eliminate local gaps, thereby reducing or even eliminating the impact of poor bottle mouth sealing caused by deviation of the tilt characteristic parameter of the bottle body. Next, the alignment deviation between the bottle mouth and the injection port is used to determine whether the injection position is qualified. Misalignment between the bottle mouth and the injection port disrupts the uniform contact state between the sealing gasket and the bottle mouth. If the bottle mouth... Compared to an eccentric seal, the seal is squeezed towards one side of the bottle opening, causing excessive compression of the seal on the contact side. This leads to plastic deformation of the material, loss of resilience, and an annular gap between the seal on the non-contact side and the bottle opening, allowing gas to leak directly through this gap. If the bottle opening is tilted relative to the seal, the contact between the seal and the bottle opening degenerates from "surface contact" to "line contact," significantly reducing the contact area. The contact pressure concentrates in the line contact area, potentially causing local stress on the seal to exceed its strength limit, forming a leakage channel and resulting in a high misjudgment rate for airtightness testing. If the position of the injection port is determined to be unqualified, the coaxiality deviation between the bottle opening and the bottle body is determined to identify whether the misalignment is causing inaccurate positioning and thus the unqualified injection port position. If the coaxiality deviation is small, the position of the injection port or the pulse frequency of the motor can be adjusted by calculating the standard deviation of the spacing to improve the sealing between the injection port and the bottle opening, further reducing the misjudgment rate of the bottle's airtightness testing results.

[0017] Furthermore, under the condition that the coaxiality deviation is small, the present invention determines the standard deviation of the spacing between several bottle mouths. A small standard deviation indicates that the spacing between each bottle mouth is relatively stable. The sealing performance of the sealing gasket and the gas injection port can be improved by moving the position of the gas injection port, thereby reducing the misjudgment rate of the bottle airtightness test results.

[0018] Furthermore, during gas injection, the present invention determines whether the bottle opening is completely sealed based on the rate of pressure increase in the bottle during the injection process. In a completely sealed state, the net increase rate of gas volume inside the bottle is equal to the inflation rate of the inflation system. If there is a leak, the net increase rate will decrease due to the gas leak, resulting in a slower rate of pressure increase. The magnitude of the rate of increase cannot completely determine whether the bottle opening is not completely sealed or whether there is a leak in the bottle. However, it can be initially determined that it is not completely sealed. The contact pressure can be appropriately increased to improve the sealing performance of the sealing gasket and the bottle opening to rule out gas leakage caused by poor sealing, thereby further reducing the misjudgment rate of the bottle airtightness test results. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the intelligent sensing system for detecting the airtightness of a bottle according to an embodiment of the present invention; Figure 2 This is an enlarged view of part A of the present invention; Figure 3 This is a structural block diagram of an intelligent sensing system for detecting the airtightness of a bottle, according to an embodiment of the present invention. Figure 4 This is a flowchart illustrating the process of determining the gas injection mode in an embodiment of the present invention; Figure 5 This is a flowchart illustrating the process of determining whether the position of the gas injection port is qualified according to an embodiment of the present invention; In the diagram: 1. Hydraulic rod, 2. Air inlet, 3. Bottle mouth, 4. Bottle body, 5. Pressure sensor, 6. Image acquisition device, 7. Fixture, 8. Chain track, 9. Gear, 10. Laser detection component. Detailed Implementation

[0020] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0021] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] Please see Figures 1-3 As shown, Figure 1 This is a schematic diagram of the intelligent sensing system for detecting the airtightness of a bottle according to an embodiment of the present invention; Figure 2 This is an enlarged view of part A of the present invention; Figure 3 This is a structural block diagram of an intelligent sensing system for detecting the airtightness of a bottle, according to an embodiment of the present invention.

[0023] The intelligent sensing system for detecting the airtightness of bottles according to embodiments of the present invention includes: Fixture 7; Several hydraulic rods 1 are mounted on the fixed frame 7 to drive the air injection port 2 to extend and retract; The data acquisition module includes an image acquisition unit 6 mounted on the fixed frame 7 to acquire several images of the bottle during the air tightness test, a pressure sensor 5 mounted at the bottom of the inflation port to acquire the pressure of the bottle, a humidity sensor (not shown in the figure) to acquire the ambient humidity, and a laser detection component 10 mounted on the fixed frame 7 to acquire the laser reflectivity of the bottle during the air tightness test. An airtightness testing module, connected to the data acquisition module, includes, The mode determination unit is used to determine the gas injection mode based on the tilt characterization parameters of the bottle body 4, whether it is low-pressure gas injection followed by high-pressure gas injection or constant-pressure gas injection. The positioning unit is used to determine the alignment deviation between the gas injection port 2 and the bottle mouth 3 based on several of the images, and to determine whether the position of the gas injection port 2 is qualified based on the comparison result between the alignment deviation and the first preset deviation. The bottle detection unit is used to determine the spacing of several bottle openings 3 based on the comparison result of the coaxiality deviation of the bottle opening 3 and the bottle body 4 with the second preset deviation when the position of the gas injection port 2 is determined to be unqualified. The gas injection position of the gas injection port 2 or the pulse frequency of the motor is adjusted according to the standard deviation of the spacing of several bottle openings 3. The gas injection correction unit is used to determine whether the bottle opening 3 is completely sealed based on the rate of increase of the bottle pressure during the gas injection process, so as to increase the contact pressure between the sealing gasket of the gas injection port 2 and the bottle opening 3 if it is determined that it is not completely sealed. An airtightness determination unit is used to determine whether the airtightness of the bottle is qualified based on the rate of decrease of the bottle pressure during the pressure holding process.

[0024] Specifically, the image acquisition device 6 can be an industrial camera, and the specific model is not limited, as long as it meets the acquisition requirements; the pressure sensor 5, for example, is an MPX5010DP, and the specific model is not limited, as long as it meets the detection requirements; the humidity sensor, for example, is a DHT11, and the specific model and installation location are not limited, as long as it meets the humidity detection requirements; the laser detection component 10 includes at least two symmetrical laser emitters and at least two polarized light receivers, and the specific model is not limited, as long as it meets the laser reflectivity detection requirements of the plastic bottle.

[0025] Specifically, in this embodiment of the invention, the plastic bottle material used for airtightness testing is made of high-density polyethylene, polypropylene, or polyethylene terephthalate.

[0026] Please see Figure 4 As shown, it is a flowchart for determining the gas injection mode in an embodiment of the present invention.

[0027] Specifically, the process of determining the tilt characterization parameters includes: The pattern determination unit acquires a first view of the bottle body 4 and acquires a second view from a direction at a 45° angle to the direction in which the first view is acquired; The pattern determination unit preprocesses the first view and the second view respectively to determine the first centerline of the first view and the second centerline of the second view; The pattern determination unit makes the first central axis and the second central axis coincide with the center point of the bottom of the bottle as the reference point; The pattern determination unit connects the midpoints of several corresponding positions of the first central axis and the second central axis to establish the true central axis of the bottle body 4; The pattern determination unit determines the angle between the actual central axis and the horizontal plane as the tilt characterization parameter.

[0028] It is understandable that in an ideal detection scenario (with no camera installation deviation and no local deformation of the bottle), the first central axis of the first view (side vertical view) is mainly affected by the imaging error in the left and right directions, while the second central axis of the second view (45° view) is mainly affected by the imaging error in the front and back directions. Moreover, the two errors are approximately the same in magnitude but opposite in direction (and are symmetrically distributed). For example, if the first central axis is slightly offset to the left by 0.5mm due to a slight leftward tilt of the bottle, and the second central axis is slightly offset to the right by 0.5mm due to a slight forward tilt of the bottle, taking the midpoint between the corresponding positions of the two can precisely cancel out the offsets in these two directions, thus approximating the position of the true central axis. This can avoid the blind spots of single-view information and supplement the tilt information in all dimensions. If the first central axis is directly taken as the true central axis, the information of the bottle's forward and backward tilt will be completely ignored. If the second central axis is directly taken, the tilt angle calculation will be biased due to the superposition of left, right, forward and backward information from a 45° perspective. However, connecting the midpoints can simultaneously integrate the effective information of the two views. The first central axis provides the basic trend of left and right tilt, and the second central axis provides the supplementary trend of forward and backward tilt. The line connecting the midpoints can cover both left, right, forward and backward tilt dimensions and avoid the information loss of a single view. For example, when the bottle tilts to the left and forward at the same time, the first central axis is offset to the left, and the second central axis is offset to the forward. The line connecting the midpoints can simultaneously reflect these two tilt directions, forming a complete 3D tilt trend.

[0029] Specifically, the mode determination unit determines the gas injection mode as low-pressure gas injection followed by high-pressure gas injection based on the comparison result of the tilt characterization parameter being less than the preset tilt characterization parameter, and determines the gas injection mode as constant-pressure gas injection based on the comparison result of the tilt characterization parameter being greater than or equal to the preset tilt characterization parameter.

[0030] Specifically, the injection pressure is the real-time pressure value of the gas inside the bottle. The specific operation process of the injection mode of low-pressure injection followed by high-pressure injection is as follows: inject gas into the bottle, hold it for 3-4 seconds when the gas pressure inside the bottle reaches 0.3MPa, and then continue to inject gas until it reaches 0.5MPa before entering the pressure holding process. Record the rate of decrease of the gas pressure inside the bottle during the pressure holding process to determine the airtightness of the bottle based on the rate of decrease. The constant pressure injection mode is to directly inject gas into the bottle until the gas pressure inside the bottle reaches 0.5MPa, and then enter the pressure holding process.

[0031] Specifically, the preset tilt characterization parameter is set to a value range of [87°, 90°], and 88° is preferred in this embodiment of the invention.

[0032] Please see Figure 5 As shown, it is a flowchart for determining whether the position of the gas injection port is qualified according to an embodiment of the present invention.

[0033] Specifically, in the corresponding gas injection mode, the positioning unit determines that the position of the gas injection port 2 is unqualified based on the comparison result that the centering deviation is greater than the first preset deviation, and determines that the position of the gas injection port 2 is qualified based on the comparison result that the centering deviation is less than or equal to the first preset deviation.

[0034] Specifically, the alignment deviation between the gas injection port 2 and the bottle mouth 3 refers to the horizontal distance between the central axis of the gas injection port 2 and the central axis of the bottle mouth 3. The first preset deviation is set to a range of [0.5mm, 1.5mm], and is preferably 1mm in this embodiment of the invention.

[0035] It is understandable that the greater the centering deviation, that is, the lower the degree of centering between the bottle mouth 3 and the air inlet 2, the worse the sealing performance of the sealing gasket and the bottle mouth 3.

[0036] Specifically, when the position of the gas inlet 2 is determined to be unqualified, the bottle detection unit determines the spacing of several bottle inlets 3 to determine the spacing standard deviation based on the comparison result that the coaxiality deviation between the bottle mouth 3 and the bottle body 4 is less than or equal to the second preset deviation, and discards the bottle body based on the comparison result that the coaxiality deviation is greater than the second preset deviation.

[0037] Specifically, the coaxiality deviation between the bottle mouth 3 and the bottle body 4 refers to the horizontal distance between the central axis of the bottle body 4 and the central axis of the bottle mouth 3. The value range of the second preset deviation is set to [1.6mm, 3mm], and 2mm is preferred in this embodiment of the invention.

[0038] Specifically, the bottle detection unit determines the injection position of the injection port 2 based on the comparison result that the standard deviation of the spacing is less than or equal to the preset standard deviation.

[0039] Specifically, the standard deviation of the spacing between bottle openings 3 refers to the standard deviation of the horizontal distance between the central axes of adjacent bottle openings 3. The preset standard deviation range is set to [0.2mm, 0.5mm], and in this embodiment of the invention, 0.3mm is preferred.

[0040] Specifically, a smaller standard deviation of the spacing indicates a smaller dispersion in the distance between the bottle openings 3, and the alignment can be improved by adjusting the position of the gas injection port 2.

[0041] Specifically, the bottle detection unit determines the moving distance of the injection position based on the average of several alignment deviations between the bottle mouth 3 and the injection port 2, after determining the injection position of the injection port 2.

[0042] Specifically, the process for determining the mean centering deviation is as follows: taking the central axis of the bottle mouth 3 as a reference, the position of the central axis of the gas injection port 2 is determined. If the position of the central axis of the gas injection port 2 falls to the left of the central axis of the bottle mouth 3, the centering deviation is determined to be a positive value. If the position of the central axis of the gas injection port 2 falls to the right of the central axis of the bottle mouth 3, the centering deviation is determined to be a negative value. The sum of several centering deviations and the quotient of the number of centering deviations are determined as the mean centering deviation.

[0043] Specifically, a pre-set correspondence between the average centering deviation and the moving distance of the gas injection position is established. The moving distance of the gas injection port 2 can be determined based on the average centering deviation. The moving direction is determined by the sign of the average centering deviation. If it is positive, the position of the gas injection port 2 is moved to the left of the central axis of the bottle mouth 3 by a corresponding moving distance. If it is negative, the position of the gas injection port 2 is moved to the right of the central axis of the bottle mouth 3 by a corresponding moving distance. The position of the gas injection port 2 is moved by the hydraulic rod 1 driven by the gear 9 on the chain track 8.

[0044] Specifically, the gas injection correction unit determines that the bottle opening 3 is not completely sealed based on a comparison result where the rising rate is less than or equal to a first preset rate, and determines that the bottle opening 3 is completely sealed based on a comparison result where the rising rate is greater than the first preset rate.

[0045] Specifically, the range of the first preset rate is set to [0.05MPa / s, 0.1MPa / s], and in this embodiment of the invention, 0.08MPa / s is preferred.

[0046] Specifically, when the gas injection correction unit determines that the bottle opening 3 is not completely sealed, it sets a number of pressure adjustment coefficients according to the first rate difference between the first preset rate and the rising rate to increase the contact pressure.

[0047] Specifically, the gas injection correction unit determines to increase the contact pressure by a first pressure adjustment coefficient based on a comparison result that the first rate difference is greater than a preset rate difference; Based on the comparison result that the first rate difference is less than or equal to the preset rate difference, the contact pressure is increased by a second pressure adjustment coefficient.

[0048] Specifically, the preset rate difference value range is set to [0.007MPa / s, 0.015MPa / s], and preferably 0.01MPa / s in this embodiment of the invention; the first pressure adjustment coefficient range is set to [1.05, 1.08], and preferably 1.06 in this embodiment of the invention; the second pressure adjustment coefficient range is set to [1.01, 1.04], and preferably 1.03 in this embodiment of the invention.

[0049] Specifically, the airtightness determination unit determines that the airtightness of the bottle is unqualified based on the comparison result of the descent rate being greater than the second preset rate, and determines that the airtightness of the bottle is qualified based on the comparison result of the descent rate being less than or equal to the second preset rate.

[0050] Specifically, the second preset rate is the rate at which the gas inside the standard bottle falls during the pressure holding process, and the value range is set to [0.003MPa / s, 0.005MPa / s]. In this embodiment of the invention, 0.003MPa / s is preferred. The standard bottle is a bottle that has passed the airtightness test.

[0051] Specifically, the airtightness determination unit determines the correction of the descent rate based on a comparison result where the ambient humidity is greater than the preset humidity, after determining that the airtightness of the bottle is qualified. Based on the comparison results of the ambient humidity being less than or equal to the preset humidity, it is determined that the rate of decrease will not be corrected.

[0052] Specifically, the preset humidity value range is set to [60%, 80%], and 70% is preferred in this embodiment of the invention.

[0053] Specifically, the airtightness determination unit, under the condition of determining the correction of the descent rate, determines to increase the descent rate by a first rate correction coefficient based on the comparison result that the laser reflectivity is greater than the preset reflectivity; Based on the comparison result that the laser reflectivity is less than or equal to the preset reflectivity, the descent rate is increased by a second rate correction coefficient.

[0054] Specifically, the preset reflectivity is set to a range of [8%, 12%], preferably 10% in this embodiment of the invention; the first rate correction coefficient is set to a range of [1.2, 1.4], preferably 1.3 in this embodiment of the invention; and the second rate correction coefficient is set to a range of [1.05, 1.19], preferably 1.15 in this embodiment of the invention.

[0055] Understandably, when ambient humidity is high, the water vapor content in the air is high, and some water vapor will enter the bottle along with the test gas during the injection process. The walls of rigid plastic bottles have a certain adsorption capacity for water vapor. Under high humidity, the bottle walls will adsorb more water vapor and form a tiny water film. This water film will hinder gas leakage. If there is a tiny leak point (such as a 0.01mm pinhole) in the bottle, gas can leak normally through the leak point in a dry environment, which is considered unqualified. However, under high humidity, water vapor easily condenses into tiny water droplets at the leak point, or the water film adsorbed on the bottle wall blocks the leak point through capillary action, resulting in a reduced gas leakage rate, and the system mistakenly judges it as airtight. Furthermore, the optical reflection / refraction characteristics and dielectric constant of the water film on the bottle body differ significantly from those of a dry bottle body. The laser reflectivity of the surface of a dry rigid plastic bottle is approximately 4%-8%, while the water film, due to its smooth surface and different refractive index compared to plastic, will form a specular reflection component, increasing the reflectivity. Therefore, the thickness of the water film can be determined based on the reflectivity value, and the descent rate can be increased accordingly to improve the accuracy of airtightness testing.

[0056] Specifically, the airtightness determination unit determines that the airtightness of the bottle is unqualified based on the comparison result that the corrected descent rate is greater than the second preset rate, and determines that the airtightness of the bottle is qualified based on the comparison result that the corrected descent rate is less than or equal to the second preset rate.

[0057] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. An intelligent sensing system for bottle tightness detection, characterized in that, The method comprises: a data acquisition module comprising an image collector configured to acquire a plurality of images of a bottle body during airtightness detection, and a pressure sensor configured to acquire a pressure of the bottle body; an airtightness detection module connected to the data acquisition module, comprising, a mode determination unit configured to determine a tilt representation parameter based on the plurality of images of the bottle body, and determine a gas injection mode as low-pressure gas injection followed by high-pressure gas injection or as constant-pressure gas injection according to the tilt representation parameter; a positioning unit configured to determine a centering deviation of a gas injection port and a bottle mouth based on the plurality of images, and determine whether the position of the gas injection port is qualified according to a comparison result of the centering deviation and a first preset deviation; a bottle body detection unit configured to, under the condition that the position of the gas injection port is determined to be unqualified, determine a distance between a plurality of bottle mouths based on a comparison result of a coaxiality deviation of the bottle mouth and the bottle body and a second preset deviation, and adjust a gas injection position of the gas injection port or a pulse frequency of a motor according to a standard deviation of the distance between the plurality of bottle mouths; a gas injection correction unit configured to determine whether the bottle mouth is completely sealed based on a rising rate of the pressure of the bottle body during gas injection, and increase a contact pressure of a sealing gasket of the gas injection port and the bottle mouth under the condition that it is determined that the bottle mouth is not completely sealed; an airtightness determination unit configured to determine whether the airtightness of the bottle body is qualified based on a falling rate of the pressure of the bottle body during pressure maintenance.

2. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 1, wherein, The tilt representation parameter is determined based on a first view and a second view of the bottle body; wherein the collection directions of the first view and the second view form an included angle of 45°.

3. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 2, wherein, The mode determination unit determines the gas injection mode as low-pressure gas injection followed by high-pressure gas injection based on a comparison result that the tilt representation parameter is less than a preset tilt representation parameter; determines the gas injection mode as constant-pressure gas injection based on a comparison result that the tilt representation parameter is greater than or equal to the preset tilt representation parameter.

4. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 3, wherein, The positioning unit determines that the position of the gas injection port is unqualified based on a comparison result that the centering deviation is greater than the first preset deviation under the corresponding gas injection mode; determines that the position of the gas injection port is qualified based on a comparison result that the centering deviation is less than or equal to the first preset deviation.

5. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 4, wherein, The bottle body detection unit, under the condition that the position of the gas injection port is determined to be unqualified, determines the distance between the plurality of bottle mouths based on a comparison result that the coaxiality deviation of the bottle mouth and the bottle body is less than or equal to the second preset deviation, and determines a standard deviation of the distance.

6. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 5, wherein, The bottle body detection unit adjusts the gas injection position of the gas injection port based on a comparison result that the standard deviation of the distance is less than or equal to a preset standard deviation.

7. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 6, wherein, The bottle body detection unit, under the condition that the gas injection position of the gas injection port is adjusted, determines a moving distance of the gas injection position based on a mean value of the centering deviation of the plurality of bottle mouths and the gas injection port.

8. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 7, wherein, The gas injection correction unit determines that the bottle mouth is not completely sealed based on a comparison result that the rising rate is less than or equal to a first preset rate.

9. The intelligent sensing system for bottle tightness detection as claimed in claim 8 wherein, The gas injection correction unit, under the condition that the bottle mouth is determined to be not completely sealed, sets a plurality of pressure adjustment coefficients according to a first rate difference between the first preset rate and the rising rate to increase the contact pressure.

10. The intelligent sensing system for airtightness testing of a bottle as claimed in claim 9, wherein, The airtightness determination unit determines that the airtightness of the bottle body is unqualified based on a comparison result that the descending rate is greater than a second preset rate; The airtightness determination unit determines that the airtightness of the bottle body is qualified based on a comparison result that the descending rate is less than or equal to the second preset rate.

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