Broken bag detection device for liquid material bag

Abstract

The invention relates to the technical field of liquid packaging bag liquid leakage detection, and particularly discloses a liquid bag breaking detection device which comprises a rack and an extrusion conveying mechanism, and the extrusion conveying mechanism comprises an upper conveying belt and a lower conveying belt; the device further comprises a visual detection system located at the output end of the extrusion conveying mechanism, the visual detection system comprises an obliquely-arranged detection channel, the detection channel comprises two parallel transparent plates, and the liquid material bag slides down from the detection channel between the two transparent plates under the action of gravity. The visual inspection system further comprises at least one image acquisition unit, the image acquisition unit is used for shooting the transparent plate to obtain image data of the transparent plate, the visual inspection system further comprises an image processing unit, and the image processing unit analyzes whether liquid material residues exist on the surface of the transparent plate or not in real time according to the image data. And an alarm signal is sent out when liquid material residual leakage is detected. The scheme is used for solving the problem that an existing detection device is not sensitive to micro-leakage detection.

Description

Technical Field

[0001] This invention relates to the field of liquid packaging bag leakage detection technology, and specifically to a device for detecting broken packaging of liquid bags. Background Technology

[0002] Currently, liquid products are typically packaged in the industry using three-side seal bags or roll film packaging, sealed with a heat sealer. However, it's common for finished products to have incomplete seals, pinholes, or tears during the manufacturing process. These issues often go undetected and leak into subsequent processes or into customers, causing serious negative impacts. The industry lacks effective methods for testing the seal of liquid bags. While significant leakage can be detected by weight checks, and insufficient seal strength can be tested by applying pressure, pinholes are difficult to detect. Furthermore, some products are the same color as the packaging bag, making it difficult to spot leaks even with the naked eye. This undoubtedly increases the difficulty of quality control throughout the entire production process.

[0003] In the prior art, Chinese patent publication number CN105883087A discloses a method and device for intelligent detection of sealed packaging bags. This method uses a compression conveyor belt to compress the packaging bag and utilizes a leakage sensor or pressure sensor to detect whether leakage has occurred. However, under this technical solution, the sensor detection method has limited sensitivity to micro-leakage or pinhole leakage, and is prone to missing detection, especially when the leakage amount is extremely small. Summary of the Invention

[0004] The present invention aims to provide a device for detecting broken packaging of liquid bags, so as to solve the problem that existing detection devices are not sensitive enough to detect micro-leakage.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A device for detecting the breakage of liquid bags includes a frame and a compression conveying mechanism mounted on the frame. The compression conveying mechanism includes an upper conveyor belt and a lower conveyor belt arranged in parallel, and the distance between the upper conveyor belt and the lower conveyor belt can be adjusted. It also includes a vision inspection system located at the output end of the extrusion conveying mechanism. The vision inspection system includes an inclined detection channel with two parallel transparent plates. The liquid bag slides down the detection channel between the two transparent plates under the action of gravity. The vision inspection system also includes at least one image acquisition unit, which is used to take pictures of the transparent plates to obtain image data of the transparent plates. The vision inspection system also includes an image processing unit, which analyzes in real time whether there is liquid residue on the surface of the transparent plates based on the image data, and issues an alarm signal when liquid leakage is detected.

[0006] The principle and advantages of this scheme are as follows: This scheme uses a compression conveying mechanism with upper and lower conveyor belts to compress the liquid bag during transport, causing liquid to seep out from any breaks in the bag. The liquid bag then slides through a detection channel composed of inclined transparent plates. If there is a leak, the liquid will adhere to the surface of the transparent plates. The image acquisition unit continuously captures images of the transparent plates, and the image processing unit compares and analyzes these images, accurately identifying subtle color or texture changes to determine if a leak has occurred. This method transforms leak detection into the identification of foreign objects against a high-contrast transparent background, greatly reducing reliance on changes in the weight of the leak or the color of the leaked liquid, and improving the detection rate of micro-leaks and pinhole leaks. Simultaneously, the inclined slide design allows for automatic transport of the liquid bag, enabling continuous detection without stopping the machine.

[0007] Preferably, as an improvement, the detection channel is installed inside a light-shielding protective cover, and an exposure lamp is installed inside the protective cover, so that the image acquisition unit can acquire high-quality image data while avoiding light pollution caused by the exposure lamp.

[0008] Preferably, as an improvement, each of the transparent plates is mounted on a movable sliding frame, with at least two transparent plates mounted side-by-side on each sliding frame. The sliding frame can move the transparent plates on it to switch between the inspection station and the standby station. This solution allows, when a transparent plate at the inspection station is identified as having liquid attached, a clean standby transparent plate can be quickly switched to the inspection station inside the protective cover by driving the sliding frame, thereby achieving rapid replacement of the inspection interface without stopping the machine, ensuring production continuity and inspection efficiency.

[0009] Preferably, as an improvement, the spare workstation is located outside the protective cover to facilitate cleaning of the transparent plate at the spare workstation.

[0010] Preferably, as an improvement, it also includes a horn-shaped feeding channel disposed between the output end of the extrusion conveying mechanism and the input end of the detection channel. The bottom surface of the horn-shaped feeding channel is arc-shaped and smoothly connected to the bottom transparent plate of the detection channel, so as to facilitate the liquid bag output by the extrusion conveying mechanism to slide accurately along the arc-shaped surface of the horn-shaped feeding channel into the detection channel.

[0011] Preferably, as an improvement, it also includes a discharge conveyor installed at the output end of the detection channel, the discharge conveyor being equipped with an end rejection mechanism, the rejection plate of the end rejection mechanism being able to push the liquid bag on the discharge conveyor to the outside of the discharge conveyor.

[0012] Preferably, as an improvement, it also includes an arc-shaped guide plate disposed between the output end of the detection channel and the discharge conveyor line. The arc-shaped guide plate causes the liquid bag to slide down the arc-shaped guide plate and then fall onto the discharge conveyor line, thereby reducing the contact impact intensity between the liquid bag and the discharge conveyor line.

[0013] Preferably, as an improvement, it also includes a weighing conveyor line set at the input end of the extrusion conveying mechanism. The weighing conveyor line includes a weighing conveying section and an auxiliary conveying section. Above the auxiliary conveying section is a first-end rejection mechanism that can reject the liquid bags on the auxiliary conveying section. This allows the first-end rejection mechanism to remove the unqualified liquid bags from the auxiliary conveying section when the weight measured by the weighing conveyor line exceeds the set range, thus preventing the unqualified liquid bags from flowing into the extrusion conveying mechanism.

[0014] Preferably, as an improvement, to ensure the accuracy of weighing, a windproof cover is installed above the weighing conveyor section to reduce the impact of airflow on the accuracy of weighing.

[0015] Preferably, as an improvement, the upper conveyor belt is supported by a total of multiple pressure sensors at both ends. When a liquid bag passes between the two conveyor belts and is under pressure, the pressure sensors will detect the pressure change. If the sealing quality of the liquid bag is poor and leakage occurs, the pressure will decrease significantly, and the sealing quality problem can be identified.

[0016] Preferably, as an improvement, each pressure sensor is connected to a height adjustment support column at its bottom. This allows the support height of the pressure sensor on the upper conveyor belt to be adjusted by adjusting the height adjustment support column after the capacity of the liquid bag changes, thereby adjusting the distance between the upper and lower conveyor belts and adapting to the squeezing pressure requirements of different liquid bags during conveying.

[0017] Preferably, as an improvement, the extrusion conveying mechanism further includes self-cleaning rollers, with both the upper and lower conveyor belts having corresponding self-cleaning rollers. The self-cleaning rollers can clean the conveying surface of the conveyor belts by contacting the conveying surface. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present invention.

[0019] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure after the angle has been adjusted.

[0020] Figure 3 for Figure 1 The main view.

[0021] Figure 4 for Figure 3 The middle section is a partial front sectional view showing the structure of the extrusion conveying mechanism and the vision inspection system.

[0022] Figure 5 for Figure 2 The three-dimensional structural diagram of the sliding frame includes one without a transparent plate and one with two transparent plates installed.

[0023] Figure 6 This is a three-dimensional structural diagram of the height-adjustable support column in this invention.

[0024] Figure 7 for Figure 6 A schematic diagram of the axial section.

[0025] The reference numerals in the accompanying drawings include: frame 100, weighing conveyor line 1, weighing conveyor section 11, windproof cover 111, auxiliary conveyor section 12, first end rejection mechanism 121, extrusion conveyor mechanism 2, upper conveyor belt 21, lower conveyor belt 22, pressure sensor 23, height adjustment support column 24, support cylinder 241, support column 242, locking nut 243, self-cleaning roller 25, vision inspection system 3, inspection channel 31, transparent plate 311, protective cover 32, image acquisition unit 33, sliding frame 34, horn feed channel 35, arc surface 351, arc guide plate 36, discharge conveyor line 4, end rejection mechanism 41, rejection plate 411, linear actuator 412. Detailed Implementation

[0026] The following detailed description illustrates the specific implementation method: The basic implementation examples are as follows: Figures 1 to 7 As shown.

[0027] A device for detecting broken liquid bags includes a frame 100 and a weighing conveyor line 1, a compression conveyor mechanism 2, a vision inspection system 3, and a discharge conveyor line 4 arranged sequentially. The weighing conveyor line 1 includes a weighing conveyor section 11 and an auxiliary conveyor section 12, which are independent belt conveyors. A head rejection mechanism 121 is provided above the auxiliary conveyor section 12 to reject liquid bags on the auxiliary conveyor section 12. This allows the head rejection mechanism 121 to remove unqualified liquid bags from the auxiliary conveyor section 12 when the weight measured by the weighing conveyor line 1 exceeds a set range, thus preventing unqualified liquid bags from flowing into the compression conveyor mechanism 2.

[0028] To ensure the accuracy of weighing on the weighing conveyor line 1, a windproof cover 111 is installed above the weighing conveyor section 11 to reduce the impact of airflow on the weighing accuracy.

[0029] The input end of the extrusion conveyor 2 is immediately connected to the output end of the weighing conveyor line 1. The extrusion conveyor 2 includes an upper conveyor belt 21 and a lower conveyor belt 22, which are arranged parallel to each other and have independent power sources. The distance between the upper conveyor belt 21 and the lower conveyor belt 22 is adjustable. Specifically, the upper conveyor belt 21 is supported by a total of four pressure sensors 23 at its two corners. Each pressure sensor 23 is connected to a height adjustment support column 24 at its bottom. When a liquid bag passes between the two conveyor belts and is subjected to pressure, the pressure sensor 23 will detect the pressure change. If the liquid bag is poorly sealed and leaks, the pressure will decrease significantly, indicating a sealing quality problem. When the capacity of the liquid bag changes, the support height of the pressure sensor 23 on the upper conveyor belt 21 is adjusted by adjusting the height adjustment support column 242, thereby adjusting the distance between the upper and lower conveyor belts 22 to adapt to the extrusion pressure requirements of different liquid bags during conveying. The drive power source of the upper conveyor belt 21 is installed above the upper conveyor belt 21 to increase its weight.

[0030] The specific height-adjustable support column 24 includes a support cylinder 241, a support column 242, and a locking nut 243. The top of the support cylinder 241 is fixedly connected to the pressure sensor 23, and the upper conveyor belt 21 is fixedly connected to the pressure sensor 23. The support column 242 is threaded inside the support cylinder 241, and the locking nut 243 is threaded on the outer periphery of the support column 242. After the support column 242 is screwed into position relative to the support cylinder 241, the relative height between the support cylinder 241 and the support column 242 is locked by the locking nut 243. The bottom of the support column 242 is tapered, and the tapered head is placed on the upper surface of the support of the lower conveyor belt 22.

[0031] To clean the upper and lower conveyor belts 22 in a timely manner, the extrusion conveyor mechanism 2 also includes self-cleaning rollers 25. Both the upper conveyor belt 21 and the lower conveyor belt 22 are equipped with self-cleaning rollers 25. The self-cleaning rollers 25 can clean the conveyor surface by contacting it.

[0032] The visual inspection system 3 is located at the output end of the extrusion conveying mechanism 2. The visual inspection system 3 includes an inclined inspection channel 31. The inspection channel 31 includes two parallel transparent plates 311. In this embodiment, the transparent plates 311 are transparent glass plates. The liquid bag slides down from the inspection channel 31 between the two transparent plates 311 under the action of gravity. The inspection channel 31 is installed inside a light-shielding protective cover 32. An exposure lamp is installed inside the protective cover 32 so that the image acquisition unit 33 can acquire high-quality image data while avoiding light pollution caused by the exposure lamp.

[0033] The visual inspection system 3 also includes an image acquisition unit 33, which is used to capture images of the transparent plate 311 to obtain image data of the transparent plate 311. In this embodiment, there is an image acquisition unit 33 corresponding to both the upper and lower transparent plates 311. The image acquisition unit 33 in this embodiment is a camera. The visual inspection system 3 also includes an image processing unit, which analyzes the image data in real time to determine whether there is any liquid residue on the surface of the transparent plate 311, and issues an alarm signal when liquid leakage is detected.

[0034] Each transparent plate 311 is mounted on a movable sliding frame 34. At least two transparent plates 311 are mounted side by side on each sliding frame 34. The sliding frame 34 can move the transparent plates 311 on it to switch between the inspection station and the standby station. The standby station is located outside the protective cover 32 to facilitate cleaning of the transparent plates 311 at the standby station. In this embodiment, each sliding frame 34 has two transparent plates 311 arranged side by side.

[0035] It also includes a horn-shaped feeding channel 35 disposed between the output end of the extrusion conveying mechanism 2 and the input end of the detection channel 31. The bottom surface of the horn-shaped feeding channel 35 is an arc-shaped surface 351, which is smoothly connected to the bottom transparent plate 311 of the detection channel 31.

[0036] It also includes an arc-shaped guide plate 36 set between the output end of the detection channel 31 and the discharge conveyor line 4. The arc-shaped guide plate 36 causes the liquid bag to slide down the arc-shaped guide plate 36 and then fall onto the discharge conveyor line 4, so as to reduce the contact impact intensity between the liquid bag and the discharge conveyor line 4.

[0037] An end rejection mechanism 41 is installed on the discharge conveyor line 4. The rejection plate 411 of the end rejection mechanism 41 can push the liquid bag on the discharge conveyor line 4 to the outside of the discharge conveyor line 4.

[0038] In this embodiment, both the first rejection mechanism 121 and the last rejection mechanism 41 can be rejection plates 411 that can move vertically along the conveyor line (the rejection plates 411 are installed at the output end of the linear driver 412, and the linear driver 412 operates according to the control system command to drive the rejection plates 411 to move along the width direction of the corresponding conveyor line). The rejection plates 411 remove unqualified liquid bags from the corresponding conveyor line.

[0039] The specific detection process in this embodiment is as follows: The produced liquid bags are weighed and tested on the weighing conveyor section 11. The checkweigher in the weighing conveyor section 11 compares the actual weight with the target weight to determine whether it is qualified. If the seal is not sealed properly, the liquid leakage will definitely cause weight abnormality and can be directly rejected.

[0040] The liquid bags that meet the weight requirements continue to be sent to the extrusion conveying mechanism 2 via the auxiliary conveying section 12. The control system judges whether leakage has occurred based on the pressure (the pressure sensed by the pressure sensor 23) of the liquid bags under continuous pressure.

[0041] After being pressurized, the liquid bag enters the vision inspection system 3. After the liquid bag passes through the inspection channel 31 composed of transparent plates 311, the image processing unit of the vision inspection system 3 analyzes the image data in real time to see if there is any liquid residue on the surface of the transparent plates 311. When liquid leakage is detected, an alarm signal is issued. For liquid bags with liquid residue detected, the control system controls the end rejection mechanism 41 to reject the liquid bag on the discharge conveyor line 4. If no liquid residue is detected, the liquid bag is considered a qualified product, and the qualified product continues to be conveyed to the next process from the discharge conveyor line 4.

[0042] This embodiment encompasses three parts: weight detection, pressure detection, and visual inspection. Weight detection primarily uses the weighing conveyor line 1 to determine the weight after sealing. For cases of significant leakage, weight alone can effectively identify the problem. The second part involves pressure detection via the extrusion conveyor mechanism 2. Pressure detection mainly inspects the sealing quality. If the sealing quality is poor and leakage occurs, there will be a noticeable decrease in pressure, indicating a sealing quality issue. However, for cases with pinholes in the packaging bag, the pressure decrease feedback may be less significant, and pressure feedback alone may not be sufficient for diagnosis. In this case, the visual inspection system 3 passes the compressed liquid bag between two transparent plates 311. A camera then takes a picture to check for any discolored residue on the glass. If discolored residue is found, it indicates that the liquid bag experienced a pinhole-like leak after pressure was applied in the pressure detection section. Based on the judgment result, the control system activates the end-of-line rejection mechanism 41 to remove the leaking liquid bag, thus completing a package breakage detection process.

[0043] In this embodiment, to avoid affecting production efficiency, the rejection mechanism is divided into two parts. One is the initial rejection mechanism 121 for cases of weight non-compliance, and the other is the final rejection mechanism 41 after pressure and visual inspection. Simultaneously, in the pressure detection section, self-cleaning rollers 25 are installed on the pressure belts. If any liquid material leaks, the residual liquid on the belt is quickly cleaned by the self-cleaning rollers 25, preventing it from affecting subsequent normal liquid material bags. Similarly, a sliding frame 34, serving as a quick-switching device, is designed on the transparent plate 311 of the detection channel 31. After one set of transparent plates 311 becomes contaminated, a spare set of transparent plates 311 can be quickly switched to continue production. The switched-off set of transparent plates 311, after cleaning, can be used as a spare transparent plate 311 for the next switch.

[0044] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A device for detecting the breakage of liquid bags, comprising a frame and a compression conveying mechanism mounted on the frame, the compression conveying mechanism including an upper conveyor belt and a lower conveyor belt arranged parallel to each other, the distance between the upper conveyor belt and the lower conveyor belt being adjustable; characterized in that: It also includes a vision inspection system located at the output end of the extrusion conveying mechanism. The vision inspection system includes an inclined detection channel with two parallel transparent plates. The liquid bag slides down the detection channel between the two transparent plates under the action of gravity. The vision inspection system also includes at least one image acquisition unit, which is used to take pictures of the transparent plates to obtain image data of the transparent plates. The vision inspection system also includes an image processing unit, which analyzes in real time whether there is liquid residue on the surface of the transparent plates based on the image data, and issues an alarm signal when liquid leakage is detected.

2. The device for detecting breakage of liquid bags according to claim 1, characterized in that: The detection channel is installed inside a light-shielding protective cover, and an exposure lamp is installed inside the protective cover.

3. The device for detecting breakage of liquid bags according to claim 2, characterized in that: Each of the transparent panels is mounted on a movable sliding frame, with at least two transparent panels mounted side by side on each sliding frame. The sliding frame can move the transparent panels on it to switch between the inspection station and the standby station.

4. The device for detecting breakage of liquid bags according to claim 3, characterized in that: The backup workstation is located outside the protective cover.

5. The device for detecting breakage of liquid bags according to claim 3, characterized in that: It also includes a horn-shaped feeding channel located between the output end of the extrusion conveying mechanism and the input end of the detection channel. The bottom surface of the horn-shaped feeding channel is arc-shaped and smoothly connected to the bottom transparent plate of the detection channel.

6. The device for detecting breakage of liquid bags according to claim 3, characterized in that: It also includes a discharge conveyor line installed at the output end of the detection channel, which is equipped with an end rejection mechanism. The rejection plate of the end rejection mechanism can push the liquid bag on the discharge conveyor line to the outside of the discharge conveyor line.

7. The device for detecting breakage of liquid bags according to claim 6, characterized in that: It also includes an arc-shaped guide plate installed between the output end of the detection channel and the discharge conveyor line.

8. A device for detecting the breakage of liquid bags according to any one of claims 1-7, characterized in that: It also includes a weighing conveyor line installed at the input end of the extrusion conveyor mechanism. The weighing conveyor line includes a weighing conveyor section and an auxiliary conveyor section. Above the auxiliary conveyor section is a head rejection mechanism that can reject the liquid bags on the auxiliary conveyor section.

9. A device for detecting the breakage of liquid bags according to any one of claims 1-7, characterized in that: The upper conveyor belt is supported by a total of multiple pressure sensors at both ends.

10. A device for detecting the breakage of liquid bags according to any one of claims 1-7, characterized in that: The extrusion conveying mechanism also includes self-cleaning rollers. Both the upper and lower conveyor belts have corresponding self-cleaning rollers, and the self-cleaning rollers can abut against the conveying surface of the conveyor belts.

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