A beef jerky packaging positioning and empty package intelligent detection device and method based on industrial vision

Abstract

The application belongs to the technical field of packaging equipment, and particularly relates to a beef jerky packaging positioning and empty package intelligent detection device and method based on industrial vision, which comprises a transmission base, a filling and detection turntable mechanism and a vacuum and heat sealing turntable mechanism; and a transfer mechanism arranged in a transition area between the filling station and the vacuum chamber. The transfer mechanism comprises a V-shaped scraping clamp used for scraping and folding the bag opening edge when the packaging bag moves; and elastic tensioning clamping jaws arranged on both sides of the vacuum chamber inlet and used for clamping the two sides of the bag opening and applying radial tension before heat sealing of the packaging bag. The bag opening of the packaging bag is first flattened and clamped by the tapered guide of the V-shaped scraping clamp, and then seamlessly enters the clamping range of the elastic tensioning clamping jaws and is locked, and the bag opening is tensioned to both sides before heat sealing. The application can flatten the packaging bag after filling, tension the bag opening before heat sealing, and simultaneously provide an empty package detection method with reliable detection principle and strong anti-interference capability.

Description

Technical Field

[0001] This invention belongs to the field of packaging equipment technology, specifically relating to a device and method for intelligent positioning and empty package detection of beef jerky packaging based on industrial vision. Background Technology

[0002] The beef jerky vacuum packaging machine is a commercial piece of equipment used for vacuum packaging of food, especially suitable for packaging snack foods such as beef jerky. Its working principle is to use a vacuum pump to extract the air from the packaging bag and perform heat sealing in a vacuum environment.

[0003] Problems with existing technology: Existing equipment tends to cause the bag opening edge to fold outwards and wrinkle after filling, resulting in low sealing strength and easy air leakage; the negative pressure inside the bag during vacuuming causes the bag opening to contract inwards, and the unsecured bag opening folds, leading to heat sealing failure or skewed sealing; existing equipment lacks a pre-shaping and tensioning mechanism for the bag opening, and the sealing quality relies heavily on the operator's experience to adjust, resulting in low production efficiency and high scrap rate. Existing equipment only uses visual devices for empty package detection. Visual detection technology is easily affected by the reflection and fog formed by beef fat inside the packaging bag, which can lead to camera misjudgment. It is also affected by the wrinkles and changes in the transparency of the packaging bag, which can interfere with the image recognition algorithm. The detection dimension is limited and it cannot distinguish abnormal states such as missing packages or broken bags. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for intelligent positioning and empty package detection of beef jerky packaging based on industrial vision. It can flatten the packaging bag after filling and tighten the bag opening before heat sealing. At the same time, it provides an empty package detection method with reliable detection principle and strong anti-interference ability.

[0005] The specific technical solution adopted by this invention is as follows: An intelligent detection device for positioning and empty packages of beef jerky based on industrial vision includes a transmission base, a filling and detection turntable mechanism and a vacuum and heat sealing turntable mechanism rotatably arranged on the transmission base, a plurality of filling stations for carrying packaging bags distributed circumferentially along the filling and detection turntable mechanism, and a plurality of vacuum chambers for vacuuming and heat sealing distributed circumferentially along the vacuum and heat sealing turntable mechanism. A transfer mechanism is set in the transition area between the filling station and the vacuum chamber. The transfer mechanism includes a V-shaped flattening clamp. The opening width of the V-shaped flattening clamp gradually decreases along the direction of the movement of the packaging bag with the turntable. It is used to flatten and gather the edge of the bag opening when the packaging bag moves. Elastic tensioning grippers are provided on both sides of the vacuum chamber inlet. The elastic tensioning grippers have an elastic pre-tightening force that closes inward, and are used to clamp the two sides of the bag opening and apply radial tension force before the packaging bag is heat-sealed. The V-shaped flattening clamp and the clamping inlet of the elastic tensioning claw are sequentially connected on the movement trajectory of the packaging bag, so that the bag opening is first flattened and clamped by the gradually shrinking guide of the V-shaped flattening clamp, and then seamlessly enters the clamping range of the elastic tensioning claw and is locked, and the bag opening is tensioned to both sides before heat sealing.

[0006] The transfer mechanism also includes a transfer arm, and a cylinder is fixedly installed at the top of the transfer arm. A wheel frame is assembled at the output end of the cylinder. The V-shaped leveling clamp is assembled on the housing of one output end of the cylinder, and the V-shaped leveling clamp consists of a fixed clamping plate and a movable clamping plate. The cylinder controls the wheel frame to roll along the outer wall of the movable clamping plate, controlling the V-shaped scraping clamp to gradually close from the tip to the open end.

[0007] The vacuum chamber includes a chamber shell. A chamber door is assembled on the front of the chamber shell via a top hinge frame. A connecting rod is connected to the end of the hinge frame. A connecting arm is hinged to the bottom of the back of the chamber shell, and the end of the connecting arm is connected to the connecting rod. A stop wheel is assembled on the outer wall of the middle part of the connecting arm.

[0008] The surface of the transmission base is fixedly installed with a door trigger guide. The outer wall of the door trigger guide and the sequential connection between the V-shaped flat clamp and the elastic tensioning claw, as well as the unloading station, are all set as bottom groove sections. The outer wall of the door trigger guide, excluding the bottom groove section, is set as top groove section. As the abutment wheel on the outer wall of the connecting arm moves from the top groove section to the bottom groove section along the smooth slope, the connecting arm deflects and opens the compartment door by being pulled and rotated by the connecting rod.

[0009] The two sides inside the casing are rotatably assembled with bag clamping rods. The bottom end of one of the bag clamping rods is fixedly connected to a connecting arm 2. One end of the connecting arm 2 is connected to the bottom end of the other bag clamping rod through a connecting rod 2. The other end of the connecting arm 2 is rotatably assembled with a stop wheel 2.

[0010] A bag clamp triggering guide is fixedly installed on the surface of the transmission base. The bag clamp triggering guide consists of an arc-shaped frame and irregularly shaped frames distributed at the sequential connection points and the unloading station. The edge of the curved frame is set as a rounded edge segment in the shape of an arc, the irregular frame has a comma-shaped structure, the edge of the irregular frame is provided with a deep groove segment, and the tail extension end of the irregular frame forms a shallow protrusion segment. When the second abutment wheel moves along the circular edge section, the elastic tensioning claw is in the unfolded state; the circular edge section and the deep groove section are sequentially connected on the movement trajectory of the second abutment wheel, and when the second abutment wheel moves along the deep groove section, the elastic tensioning claw is in the closing process; and when the second abutment wheel moves along the shallow protrusion section, the elastic tensioning claw is in the slightly open process.

[0011] A set of elastic tensioning grippers includes a first gripper arm and a second gripper arm. The first gripper arm is fixedly installed on the top of the corresponding bag gripper rod, and a clamping plate seat is slidably assembled at the end of the first gripper arm. An arc-shaped clamping plate is detachably assembled on the side wall of the clamping plate seat near the second gripper arm.

[0012] The inner walls on both sides of the hull are fixedly installed with bases, the second clamping arm is slidably assembled on the top of the corresponding base, and the side wall of the second clamping arm near the clamping plate seat is detachably assembled with an arc-shaped clamping plate. The bottom end of the heat-sealing plate is fixedly assembled with a strip plate, and both sides of the strip plate are hinged with strip arms, and the ends of the strip arms are connected to the corresponding arc-shaped clamps. As the heat-sealing plate approaches the opening of the packaging bag, the elastic tensioning jaws driven by the belt arm clamp the opening of the bag and tension it to both sides.

[0013] A smart detection method for empty beef jerky packaging based on industrial vision, the specific steps of which are as follows: When the position encoder detects that the vacuum chamber has reached the vacuuming station and the mold is closed, it triggers the vacuum pump group to start. At the same time, the high-frequency pressure sensor collects the pressure-time sequence within a preset time window and transmits it to the main controller. The main controller performs a moving average filter on the sequence, calculates the first derivative to extract the absolute value of the maximum pressure drop rate, and calculates the second derivative to detect whether there is a gas release inflection point that changes from negative to positive. The main controller compares the maximum pressure drop rate with a preset threshold. If it is greater than the threshold and no gas release inflection point is detected, it is determined to be an empty package and an empty package status code is written into the internal shift register. The preset threshold is dynamically calculated based on the average value and standard deviation of the maximum pressure drop rate of historical real packages. The shift register shifts synchronously with the pulse of the position encoder. When the station corresponding to the empty package status code reaches the sealing station, the main controller shields the heating sealing signal. When it reaches the unloading station, the main controller triggers the high-pressure blowing valve to blow out the empty package.

[0014] A computer device includes: a memory and a processor, the memory and the processor being connected via a bus; the memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, characterized in that: when the computer programs / instructions are executed by the processor, an intelligent method for detecting empty packets is implemented.

[0015] The technical effects achieved by this invention are as follows: The V-shaped flattening clamp used in this invention reduces and closes from one end to the other, forcibly gathering and flattening the edge of the packaging bag opening, ensuring that the bag opening is fully open and flat before entering the next work station.

[0016] When the vacuum chamber is transported to the sequential connection point, the chamber door opens completely by itself, and the elastic tensioning jaws close automatically and clamp the packaging bag sent into the vacuum chamber. Neither of these actions requires additional electrical equipment for control, and the actions are fully automated while reducing energy consumption.

[0017] After the packaging bag is vacuumed in the corresponding vacuum chamber and before heat sealing, the elastic tensioning claws on both sides move in opposite directions, which can make the bag opening tighten to both sides at the same time. This lateral tension keeps the bag opening in a slightly tense state, ensuring that the bag opening fits flat against the heat sealing plate and preventing the bag opening from loosening and wrinkling during heat sealing.

[0018] Based on visual inspection, this invention also provides a method for detecting empty packages by analyzing vacuum pumping curves. It distinguishes empty packages from full packages by utilizing the essential physical differences in "gas volume" and "gas release characteristics". The detection principle is reliable, accurately identifies abnormalities such as missing packages and broken bags, has strong anti-interference ability, and is not affected by beef fat, color, packaging bag wrinkles, transparency, etc. Moreover, the detection process is completely synchronized with the vacuuming process, without adding extra processing time; it does not change the core components such as the turntable and vacuum chamber, and the modification cycle is short. Attached Figure Description

[0019] Figure 1 This is a front view structural diagram of the packaging positioning and detection device provided in an embodiment of the present invention; Figure 2 This is a rear view structural diagram of the packaging positioning and detection device provided in an embodiment of the present invention; Figure 3 yes Figure 1 A magnified view of the structure at point A in the middle; Figure 4 This is a structural diagram of the transfer mechanism provided in an embodiment of the present invention; Figure 5 This is a partial structural diagram of the door trigger guide and the bag clamp trigger guide provided in an embodiment of the present invention; Figure 6 This is a structural diagram of a single vacuum chamber provided in an embodiment of the present invention; Figure 7 This is a rear view structural diagram of the vacuum chamber provided in an embodiment of the present invention; Figure 8 This is a bottom view of the vacuum chamber provided in an embodiment of the present invention; Figure 9 This is a cross-sectional view of the vacuum chamber provided in an embodiment of the present invention; Figure 10 yes Figure 9 A magnified view of the structure at point B in the middle; Figure 11 This is a flowchart of the intelligent empty packet detection method provided in an embodiment of the present invention.

[0020] The attached diagram lists the components represented by each number as follows: 1. Transmission base; 2. Packaging bag supply mechanism; 3. Filling and inspection turntable mechanism; 301. Mechanical gripper; 4. Spreading frame mechanism; 5. Inspection frame; 501. Guide rod; 502. Industrial vision camera; 6. Transfer mechanism; 601. Support frame; 602. Transfer arm; 603. Servo motor; 604. Cylinder 1; 605. Fixed clamping plate; 606. Movable clamping plate; 607. Wheel frame; 7. Vacuum and heat sealing turntable mechanism; 8. Vacuum chamber; 801. Chamber shell; 802. Hinge frame; 803. Chamber door; 804. Connecting rod 1; 805. Connecting arm 1; 806. Abutment wheel 1; 807. Air pump connection pipe; 808. Bag clamp contact rod; 809. Connecting arm 2; 810. Connecting rod 2; 811. Abutment wheel 2; 812. Clamping arm 1; 813. Clamping plate seat; 814. Slider; 815. Spring; 816. Arc-shaped clamping plate 1; 817. Base; 818. Clamping arm 2; 819. Arc-shaped clamping plate 2; 820. Cylinder 2; 821. Heat sealing plate; 822. Belt plate; 823. Belt arm; 824. High-frequency pressure sensor; 9. Door trigger guide; 901. Top groove section; 902. Bottom groove section; 10. Bag clamp trigger guide; 1001. Arc-bending frame; 1002. Irregular frame; 1003. Round edge section; 1004. Deep groove section; 1005. Shallow protrusion section; 11. Discharge conveying mechanism; 12. Main controller. Detailed Implementation

[0021] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention.

[0022] like Figures 1-10 As shown, a beef jerky packaging positioning and empty package intelligent detection device based on industrial vision includes a transmission base 1, a filling and detection turntable mechanism 3 and a vacuum and heat sealing turntable mechanism 7 rotatably mounted on the transmission base 1, and multiple filling stations for carrying packaging bags distributed circumferentially along the filling and detection turntable mechanism 3. A packaging bag supply mechanism 2 for replenishing packaging bags into each filling station is provided on one side of the surface of the transmission base 1. Each filling station of the filling and detection turntable mechanism 3 is equipped with a mechanical claw 301 for clamping the packaging bag, and an opening frame mechanism 4 for opening the bag opening of the corresponding filling station is provided on the surface of the transmission base 1 at the beef jerky filling position. A detection frame 5 is provided on the surface of the transmission base 1 along the direction of movement of the packaging bag with the filling and detection turntable mechanism 3 and near the transfer mechanism 6. A guide rod 501 and an industrial vision camera 502 are respectively installed on both sides of the top end of the detection frame 5. When the packaging bag moves in contact with the guide rod 501, the industrial vision camera 502 completes visual inspection. Multiple vacuum chambers 8 for vacuuming and heat sealing are distributed circumferentially along the vacuum and heat sealing turntable mechanism 7. Each vacuum chamber 8 includes a chamber shell 801. A gas pump pipe 807 for connecting to a vacuum pump is provided on one side of the back of the chamber shell 801. A cylinder 820 is fixedly installed at the top of the back of the chamber shell 801. The output end of the cylinder 820 extends into the interior of the chamber shell 801 and is fitted with a heat sealing plate 821. A high-frequency pressure sensor 824 for detecting the internal air pressure is installed on one side of the top of the chamber shell 801 to collect the absolute pressure value inside the vacuum chamber 8 in real time. The transmission base 1 is equipped with a material discharge and conveying mechanism 11 and a high-pressure air pipe with a solenoid valve at the unloading station of the vacuum and heat sealing turntable mechanism 7. The main drive shafts of the filling and detection turntable mechanism 3 and the vacuum and heat sealing turntable mechanism 7 are equipped with position encoders to output the angular displacement signal of the turntable in real time, and to provide the main controller 12 with precise synchronous trigger signals for each station. The main controller 12 is internally equipped with a data acquisition module, a feature extraction module, a logic determination module, and a shift register, which are used to process pressure data and output control commands.

[0023] According to the above structure, the packaging bags are successively replenished into each filling station of the filling and detection turntable mechanism 3 by the packaging bag supply mechanism 2. When the packaging bags move to the beef jerky filling station along the movement direction of the filling and detection turntable mechanism 3, the packaging bags at each filling station are opened by the support frame mechanism 4, and beef jerky is injected into the packaging bags through the filling mechanism. The visual detection station continues to move with the turntable. When the packaging bags move in conjunction with the guide rod 501, the industrial vision camera 502 completes the visual detection to observe whether each packaging bag is properly filled. The above process is all existing technology and will not be described in detail here.

[0024] Example 1: like Figure 2 and Figure 4 As shown, the transfer mechanism 6 is located in the transition area between the filling station and the vacuum chamber 8. The transfer mechanism 6 includes a V-shaped flattening clamp. The opening width of the V-shaped flattening clamp gradually decreases along the direction of the bag's movement with the turntable. It is used to flatten and gather the bag opening edge when the bag moves. The transfer mechanism 6 also includes a support frame 601 fixedly installed on the surface of the transmission base 1. The end of the support frame 601 is mechanically hinged to a transfer arm 602 via a servo motor 603. A cylinder 604 is fixedly installed at the top of the transfer arm 602. A V-shaped leveling clamp is assembled on the housing at the output end of the cylinder 604. The V-shaped leveling clamp consists of a fixed clamping plate 605 fixedly installed on the housing at the output end of the cylinder 604 and a movable clamping plate 606 hinged to the fixed clamping plate 605. A wheel frame 607 is assembled at the output end of the cylinder 604. The cylinder 604 controls the wheel frame 607 to roll along the outer wall of the movable clamping plate 606, and controls the V-shaped leveling clamp to gradually close from the tip to the open end.

[0025] According to the above structure, when the packaging bag moves to the transfer mechanism 6 along the direction of the filling and detection turntable mechanism 3, the bag opening automatically enters through the opening of the V-shaped flattening clamp. The cylinder 604 then starts and controls the wheel frame 607 to roll along the outer wall of the movable clamp 606. The movable clamp 606 gradually approaches the fixed clamp 605 from the hinge end to the other end until the V-shaped flattening clamp is completely closed and clamps the packaging bag. Since the V-shaped flattening clamp closes from one end to the other, the edge of the packaging bag opening is forcibly gathered and flattened to ensure that the bag opening is fully open and flat before entering the next station. Then the servo motor 603 starts and the transfer arm 602 rotates, and the packaging bag is then sent into the corresponding vacuum chamber 8.

[0026] like Figures 5-7 As shown, the front of the shell 801 is equipped with a door 803 that can be opened and closed via a top hinge frame 802. The end of the hinge frame 802 is connected to a connecting rod 804. The bottom of the back of the shell 801 is hinged to a connecting arm 805, and the end of the connecting arm 805 is connected to the connecting rod 804. The outer wall of the middle part of the connecting arm 805 is equipped with a stop wheel 806. A door trigger guide 9 is fixedly installed on the surface of the transmission base 1 and around the vacuum and heat sealing turntable mechanism 7. The outer wall of the door trigger guide 9 is set as a bottom groove section 902 at the sequential connection of the V-shaped scraping clamp and the elastic tensioning claw and at the unloading station. The outer wall of the door trigger guide 9, excluding the bottom groove section 902, is set as a top groove section 901. The horizontal height of the bottom surface of the bottom groove section 902 is lower than the horizontal height of the bottom surface of the top groove section 901, and the junction of the bottom groove section 902 and the top groove section 901 adopts a smooth slope transition design. According to the above structure, during the process of a vacuum chamber 8 moving along the direction of motion of the vacuum and heat sealing turntable mechanism 7 to the sequential connection point, the abutment wheel 806 on the outer wall of the connecting arm 805 is moving from the top groove section 901 along the smooth slope to the bottom groove section 902. The connecting arm 805 deflects and opens the chamber door 803 by the pull of the connecting rod 804, and the packaging bag is then sent into the vacuum chamber 8. When the abutment wheel 806 leaves the bottom groove section 902 and re-enters the top groove section 901, the chamber door 803 closes.

[0027] like Figure 5 , Figures 8-10 As shown, elastic tensioning claws are arranged on both sides of the inlet of vacuum chamber 8. The elastic tensioning claws have an elastic pre-tightening force that closes inward, which is used to clamp the two sides of the bag opening and apply radial tension before the packaging bag is heat-sealed. Bag clamping contact rods 808 are rotatably assembled through both sides inside the chamber shell 801. The bottom end of one bag clamping contact rod 808 is fixedly connected to a connecting arm 809. One end of the connecting arm 809 is connected to the bottom end of the other bag clamping contact rod 808 through a connecting rod 810. The other end of the connecting arm 809 is rotatably assembled with a stop wheel 811. A bag clamp trigger guide 10 is fixedly installed on the surface of the transmission base 1 and around the vacuum and heat-sealing turntable mechanism 7. The bag clamp trigger guide 10 consists of an arc-shaped frame 1001 and irregularly shaped frames 1002 distributed at the sequential connection points and unloading stations. The edge of the arc-shaped frame 1001 is set as a rounded edge section 1003. The irregularly shaped frame 1002 has a comma-shaped structure. The edge of the irregularly shaped frame 1002 is provided with a deep groove section 1004, and the tail extension end of the irregularly shaped frame 1002 forms a shallow protrusion section 1005. When the second abutment 811 moves along the rounded edge section 1003, the elastic tensioning jaws are in the unfolded state; the rounded edge section 1003 and the deep groove section 1004 are sequentially connected on the movement trajectory of the second abutment 811, and when the second abutment 811 moves along the deep groove section 1004, the elastic tensioning jaws are in the closing process, and when the second abutment 811 moves along the shallow protrusion section 1005, the elastic tensioning jaws are in the slightly open process.

[0028] like Figures 9-10 As shown, a set of elastic tensioning grippers includes a first gripper arm 812 and a second gripper arm 818. The first gripper arm 812 is fixedly installed on the top of the corresponding bag clamp contact rod 808, and a clamping plate seat 813 is slidably assembled at the end of the first gripper arm 812. A slider 814 is installed at the bottom of the clamping plate seat 813, which forms a sliding assembly relationship with the first gripper arm 812. A spring 815 is connected between the slider 814 and the outer wall of the first gripper arm 812. An arc-shaped clamping plate 816 is detachably assembled on the side wall of the clamping plate seat 813 near the second gripper arm 818. Bases 817 are fixedly installed on the inner walls of both sides of the shell 801. Clamping arms 818 are slidably assembled on the top of the corresponding bases 817. Arc-shaped clamping plates 819 are detachably assembled on the side wall of clamping arms 818 near clamping plate seats 813. A belt plate 822 is fixedly assembled on the bottom end of the heat-sealing plate 821. Belt arms 823 are hinged on both sides of the belt plate 822, and the ends of the belt arms 823 are connected to the corresponding arc-shaped clamping plates 819.

[0029] According to the above structure, when the door 803 of a vacuum chamber 8 is opened at the sequential connection point, the abutment wheel 811 at the bottom of a bag clamping rod 808 inside moves along the deep groove section 1004. At this time, the elastic tensioning claw begins to close. Specifically, the bag clamping rod 808 will rotate. Since the connecting rod 810 connects two bag clamping rods 808 at the same time, the other bag clamping rod 808 rotates in the opposite direction at the same time. Therefore, the two arc-shaped clamping plates 816 approach the corresponding arc-shaped clamping plates 819 at the same time and complete the clamping of the packaging bag. After the door 803 is closed, when the abutment wheel 811 moves along the shallow protrusion section 1005, the elastic tensioning claw is in a slightly open process. The packaging bag is then supported in the vacuum chamber 8. The purpose of this slightly open packaging bag is to facilitate the easy release of air inside the packaging bag. After the vacuuming is completed, the clamping is restored. After the vacuuming process is completed, cylinder 820 pushes heat sealing plate 821 to press tightly against the opening of the packaging bag. Belt plate 822 moves accordingly, and via belt arm 823, clamping arms 818 on both sides move in the opposite direction. Under the squeezing contact of the arc-shaped clamping plate 816 and the arc-shaped clamping plate 819, the clamping plate seat 813 adjacent to clamping arm 818 moves accordingly and squeezes spring 815. At this time, the opening of the packaging bag simultaneously tightens to both sides. This lateral tension keeps the opening of the bag in a slightly tense state, ensuring that the opening of the bag is flatly attached to heat sealing plate 821, preventing the opening of the bag from loosening and wrinkling during heat sealing.

[0030] The working principle of this invention is as follows: the clamping inlets of the V-shaped flattening clamp and the elastic tensioning claw are sequentially connected on the movement trajectory of the packaging bag, so that the bag opening is first flattened and clamped by the gradually narrowing guide of the V-shaped flattening clamp, and then seamlessly enters the clamping range of the elastic tensioning claw inside the corresponding vacuum chamber 8 through the transfer mechanism 6 and is locked. After the vacuuming work is completed, the cylinder 820 pushes the heat sealing plate 821 close to the bag opening. The bag opening is simultaneously stretched to both sides before heat sealing. After heat sealing is completed, it falls into the discharge conveyor mechanism 11 and is sent out.

[0031] Example 2: like Figure 11 As shown, a smart detection method for empty beef jerky packaging based on industrial vision is described, and the specific steps are as follows: Step S1: Workstation Synchronization and High-Frequency Data Acquisition When the position encoder detects that the target vacuum chamber 8 rotates with the turntable to the "vacuuming station" and completes the mold closing and sealing, the main controller 12 receives the mold closing position signal and sends an opening command to the vacuum pump control valve at the same time. At the instant the vacuum pump control valve opens (t=0), the main controller 12 triggers the high-frequency pressure sensor 824 to begin collecting pressure data, setting the collection time window to [value missing]. Alternatively, a pressure threshold can be set to trigger a stop. Furthermore, the high-frequency pressure sensor 824 converts the analog signal into a digital signal, forming a discrete pressure-time series. The data is transmitted in real time to the data acquisition module of the main controller 12.

[0032] Step S2: Data Preprocessing and Noise Reduction Because high-frequency noise is generated by airflow pulsation and mechanical vibration in the initial stage of air extraction, the main controller 12 uses a moving average filtering algorithm or a Kalman filtering algorithm to process the original sequence. The process involves processing the stress sequence, specifically using a moving average filter with a window size of N to smooth it. ; Smoothed negative pressure suction output This eliminates glitch and provides a reliable data foundation for subsequent calculus calculations.

[0033] Step S3: Multidimensional negative pressure feature extraction The feature extraction module of the main controller 12 extracts the smoothed curve. Perform feature calculations in the following three dimensions: Feature 1: Initial maximum voltage drop rate Calculate the first derivative of the curve Extract the absolute value of the maximum voltage drop rate within the acquisition window. Because the air volume inside the empty package is large and the resistance is small, Significantly larger than the actual package; Feature 2: Pressure drop time integral Calculate pressure from initial atmospheric pressure Reduce to target pressure Time required And calculate the area of ​​the pressure curve integral during that time period. This reflects the overall work difference in the pumping process; Feature 3: Pore gas release inflection point Calculate the second derivative of the curve Detect whether it exists within the collection window The zero-crossing point (i.e., the inflection point) from negative to positive reflects that when the beef in the solid package contains moisture and tiny pores, it will release internal gas when the negative pressure reaches a certain level, causing the pressure drop rate to slow down, and a clear "gas release inflection point" will appear on the curve; while the empty package shows a smooth exponential decay and does not have this inflection point.

[0034] Step S4: Logical decision and status marking The main controller 12 will extract the feature vector X=[ , The inflection point state is input into the preset judgment model, and the specific judgment rules are as follows: like > , If the preset empty package pressure drop rate threshold is not met and no gas release inflection point is detected, the current packaging bag is determined to be empty. like ≤ If a gas release inflection point is detected, it is determined to be a normal solid package; like If the pressure is extremely low or cannot be reduced, it is determined that the vacuum chamber 8 is poorly sealed or the packaging bag is damaged. Based on the judgment result, the main controller 12 writes a status code to the workstation address corresponding to the vacuum chamber 8 in its internal shift register. Specifically, 00 represents an empty package, 01 represents a full package, and 10 represents a broken bag.

[0035] Step S5: Closed-loop control and elimination based on shift registers As the dual turntables rotate, the position encoder continuously sends pulses, and the shift register in the main controller 12 shifts synchronously according to the pulses to ensure that the status code is strictly consistent with the position of the physical vacuum chamber 8. Furthermore, when the station with status code 00 rotates to the "heat sealing station", the main controller 12 blocks the heating and pressing output signals of the station; at this time, the vacuum chamber 8 opens, and the empty bag remains unsealed to prevent the packaging material from being heat-sealed and to facilitate subsequent recycling.

[0036] Furthermore, when the station continues to rotate to the "discharge / unloading station", the main controller 12 reads status code 00 and triggers the high-pressure blowing solenoid valve set at the station. The high-pressure airflow blows the unsealed empty bag into the waste collection trough. If 01 is read, the mechanical gripper is controlled to open normally and the full bag falls into the finished product conveyor belt.

[0037] Step S6: Adaptive Benchmark Update To overcome curve drift caused by changes in ambient air pressure and aging of the vacuum pump, the system includes an adaptive update mechanism, specifically: The main controller 12 counts the M most recent feature vectors that have been identified as "real packets" and calculates their... average and standard deviation Dynamically adjust the empty packet threshold, i.e. ,in, The confidence coefficient is used; the updated threshold automatically overwrites the original threshold, enabling the system to learn automatically without maintenance.

[0038] This method distinguishes empty and full packages by utilizing the essential physical differences in "gas volume" and "gas release characteristics". The detection principle is reliable, has strong anti-interference ability, and is not affected by beef fat, color, packaging bag wrinkles, transparency, etc. The detection process is completely synchronized with the vacuuming process, without adding extra process time; it does not change the core components such as turntable and vacuum chamber, and the modification cycle is short.

[0039] The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained in this invention are implemented according to conventional methods in the art unless otherwise specified or limited.

Claims

1. A beef jerky packaging positioning and empty package intelligent detection device based on industrial vision, comprising a transmission base (1), a filling and detection turntable mechanism (3) and a vacuum and heat sealing turntable mechanism (7) rotatably disposed on the transmission base (1), a plurality of filling stations for carrying packaging bags distributed circumferentially along the filling and detection turntable mechanism (3), and a plurality of vacuum chambers (8) for vacuuming and heat sealing distributed circumferentially along the vacuum and heat sealing turntable mechanism (7), characterized in that: The transfer mechanism (6) is located in the transition area between the filling station and the vacuum chamber (8). The transfer mechanism (6) includes a V-shaped flattening clamp. The opening width of the V-shaped flattening clamp gradually decreases along the direction of the movement of the packaging bag with the turntable. It is used to flatten and gather the edge of the bag opening when the packaging bag moves. Elastic tensioning grippers are provided on both sides of the inlet of the vacuum chamber (8). The elastic tensioning grippers have an elastic pre-tightening force that closes inward and are used to clamp the two sides of the bag opening and apply radial tension before the packaging bag is heat-sealed. The V-shaped flattening clamp and the clamping inlet of the elastic tensioning claw are sequentially connected on the movement trajectory of the packaging bag, so that the bag opening is first flattened and clamped by the gradually shrinking guide of the V-shaped flattening clamp, and then seamlessly enters the clamping range of the elastic tensioning claw and is locked, and the bag opening is tensioned to both sides before heat sealing.

2. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 1, characterized in that: The transfer mechanism (6) also includes a transfer arm (602), and a cylinder (604) is fixedly installed at the top of the transfer arm (602). A wheel frame (607) is assembled at the output end of the cylinder (604). The V-shaped leveling clamp is assembled on the housing at the output end of cylinder one (604), and the V-shaped leveling clamp consists of a fixed clamping plate (605) and a movable clamping plate (606); The cylinder (604) controls the wheel frame (607) to roll along the outer wall of the movable clamp (606), and controls the V-shaped scraper clamp to gradually close from the tip to the open end.

3. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 1, characterized in that: The vacuum chamber (8) includes a chamber shell (801). The front of the chamber shell (801) is equipped with a door (803) that can be opened and closed through a top hinge frame (802). The end of the hinge frame (802) is connected to a connecting rod (804). The bottom of the back of the chamber shell (801) is hinged to a connecting arm (805), and the end of the connecting arm (805) is connected to the connecting rod (804). The outer wall of the middle part of the connecting arm (805) is equipped with a stop wheel (806).

4. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 3, characterized in that: The transmission base (1) is fixedly installed with a door trigger guide (9). The outer wall of the door trigger guide (9) and the area located at the sequential connection and the unloading station are both set as bottom groove section (902). The area of ​​the outer wall of the door trigger guide (9) excluding the bottom groove section (902) is set as top groove section (901). As the abutment wheel 1 (806) on the outer wall of the connecting arm 1 (805) moves from the top groove section (901) along the smooth slope to the bottom groove section (902), the connecting arm 1 (805) deflects and opens the compartment door (803) by the pulling and rotating of the connecting rod 1 (804).

5. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 4, characterized in that: The two sides inside the housing (801) are rotatably assembled with bag clamping rods (808). The bottom end of one of the bag clamping rods (808) is fixedly connected to a connecting arm (809). One end of the connecting arm (809) is connected to the bottom end of the other bag clamping rod (808) through a connecting rod (810). The other end of the connecting arm (809) is rotatably assembled with a stop wheel (811).

6. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 5, characterized in that: The transmission base (1) is fixedly mounted with a bag clamp trigger guide (10), which is composed of an arc-shaped frame (1001) and irregularly shaped frames (1002) distributed at the sequential connection and unloading station. The edge of the curved frame (1001) is set as a rounded edge segment (1003) in the shape of an arc, the irregular frame (1002) has a comma-shaped structure, the edge of the irregular frame (1002) is provided with a deep groove segment (1004), and the tail extension end of the irregular frame (1002) is formed with a shallow protrusion segment (1005). When the second abutment (811) moves along the rounded edge section (1003), the elastic tensioning jaws are in an unfolded state; the rounded edge section (1003) and the deep groove section (1004) are sequentially connected on the movement trajectory of the second abutment (811), and when the second abutment (811) moves along the deep groove section (1004), the elastic tensioning jaws are in a closing process; and when the second abutment (811) moves along the shallow protrusion section (1005), the elastic tensioning jaws are in a slightly open process.

7. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 5, characterized in that: A set of elastic tensioning grippers includes a first gripper arm (812) and a second gripper arm (818). The first gripper arm (812) is fixedly installed on the top of the corresponding bag clamping contact rod (808), and a clamping plate seat (813) is slidably assembled at the end of the first gripper arm (812). An arc-shaped clamping plate (816) is detachably assembled on the side wall of the clamping plate seat (813) near the second gripper arm (818).

8. The intelligent detection device for beef jerky packaging positioning and empty packages based on industrial vision according to claim 7, characterized in that: The inner walls on both sides of the housing (801) are fixedly installed with bases (817), and the second clamping arm (818) is slidably assembled on the top of the corresponding base (817). The second clamping arm (818) is detachably assembled with an arc-shaped clamping plate (819) on the side wall near the clamping plate seat (813). The bottom end of the heat-sealing plate (821) is fixedly assembled with a strip plate (822), and both sides of the strip plate (822) are hinged with strip arms (823), and the ends of the strip arms (823) are connected to the corresponding arc-shaped clamping plate (819). As the heat-sealing plate (821) approaches the opening of the packaging bag, the elastic tensioning jaws driven by the belt arm (823) clamp the opening of the bag to both sides and tighten it.

9. A method for intelligent detection of empty packages in beef jerky packaging based on industrial vision, using the beef jerky packaging positioning and empty package intelligent detection device as described in any one of claims 1-8, characterized in that, The specific steps are as follows: When the position encoder detects that the vacuum chamber (8) has reached the vacuum pumping station and the mold is closed, it triggers the vacuum pump group to start. At the same time, the high-frequency pressure sensor (824) collects the pressure-time sequence within the preset time window and transmits it to the main controller (12). The main controller (12) performs a moving average filter on the sequence, calculates the first derivative to extract the absolute value of the maximum pressure drop rate, and calculates the second derivative to detect whether there is a gas release inflection point that changes from negative to positive. The main controller (12) compares the maximum pressure drop rate with the preset threshold. If it is greater than the threshold and no gas release inflection point is detected, it is determined to be an empty package and writes the empty package status code into the internal shift register. The preset threshold is dynamically calculated based on the average value and standard deviation of the maximum pressure drop rate of historical real packages. The shift register shifts synchronously with the pulse of the position encoder. When the station corresponding to the empty package status code reaches the sealing station, the main controller (12) shields the heating sealing signal. When it reaches the unloading station, the main controller (12) triggers the high-pressure blowing valve to blow out the empty package.

10. A computer device, comprising: A memory and a processor, the memory and the processor being connected via a bus; The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions, characterized in that: when the computer programs / instructions are executed by the processor, they implement the empty packet intelligent detection method of claim 9.

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