A system and method for detecting heat seal performance of a food composite film

Abstract

The present application belongs to the technical field of food composite film production, and particularly relates to a heat sealing performance detection system and method for food composite film, which comprises a rotary film loading assembly, a heat sealing assembly, a qualitative detection assembly for air tightness and peeling performance, and a qualitative detection assembly for compression resistance. The present application integrates air tightness, peeling resistance and compression resistance into one through a multi-station rotary structure. Meanwhile, the film loading plate made of the same material as the to-be-detected packaging object can simulate the actual heat sealing working conditions of containers made of different materials, and realize differentiated scene detection. During detection, all items can be detected through single clamping, and multi-dimensional qualitative detection can be completed through air pressure monitoring, friction peeling and free fall impact, so that the process is simple and efficient. The present application fills the technical gap of single detection dimension and poor material adaptability, and the detection result is consistent with the actual application scene, which can effectively optimize the heat sealing process of composite film, reduce production loss, and meet the batch quality inspection demand of food packaging.

Description

Technical Field

[0001] This invention belongs to the field of food composite film production technology, specifically relating to a heat-sealing performance testing system and method for food composite films. Background Technology

[0002] Food composite films, with their lightweight, flexibility, excellent barrier properties, and superior sealing performance, are indispensable packaging materials in the modern food industry. The heat-sealing performance of composite films is a key indicator of the reliability of food packaging seals, storage and transportation stability, and product shelf life. The quality of the heat seal directly affects whether food products experience leaks, moisture absorption, spoilage, or seepage, and is a crucial foundation for ensuring the safety of food storage, transportation, and sales. Therefore, comprehensive testing of the heat-sealing performance of food composite films is a critical step in food packaging production quality control, process optimization, and product compliance testing, and is of significant practical importance for improving food packaging quality, mitigating food safety risks, and reducing production losses for enterprises.

[0003] Existing heat-sealing performance testing systems for food composite films have several shortcomings. First, they are limited in function and cannot achieve integrated testing of airtightness, peel resistance, and compressive strength. The testing process requires multiple equipment changes, sample re-clamping, and parameter adjustments, resulting in cumbersome procedures and low overall testing efficiency. Second, they cannot simulate the differentiated testing conditions of food composite films after heat sealing with containers of different materials.

[0004] In summary, current testing equipment for the heat-sealing performance of food composite films suffers from fragmented functions, low testing efficiency, poor material compatibility, and limited testing dimensions, making it difficult to meet the industry's demand for integrated, precise, and systematic testing of composite film heat-sealing performance. Therefore, developing a food composite film heat-sealing performance testing system and method that integrates multiple tests such as airtightness, pressure resistance, and peel strength, and is adaptable to the testing needs of heat-sealing containers made of different materials, is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned problems in the prior art and to provide a system and method for testing the heat-sealing performance of food composite films.

[0006] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution: A heat-sealing performance testing system for a food composite film includes a reusable film assembly, a heat-sealing assembly, a qualitative testing assembly for air tightness and peel performance, and a qualitative testing assembly for compressive strength. The reusable film assembly is provided with a feeding station, a heat-sealing station, a qualitative testing station for air tightness and peel performance, a qualitative testing station for compressive strength, and a discharging station along its circumferential direction. The recirculating film loading assembly includes a rotating base plate, a fixed support tube, a movable support tube, a lower turntable, an upper turntable, a rotating drive motor, a drive gear, a film carrier plate, a toggle motor, and a toggle gear. The movable support tube is movably supported on the upper side of the rotating base plate via the fixed support tube. The rotating drive motor is mounted on the upper side of the rotating base plate, and a drive gear is mounted on the output end of the rotating drive motor. A rotating tooth groove that meshes with the drive gear is opened on the inner side of the movable support tube. The lower turntable is fixed to the upper end of the movable support tube. The upper turntable is mounted on the upper side of the lower turntable, and together with the upper turntable, several film carrier plates capable of radial displacement are clamped and restricted. The toggle motor is mounted on the lower side of the lower turntable, and a toggle gear is mounted on the output end of the toggle motor. The film carrier plate has stepped film carrier holes for easy reception of food composite film, and a toggle tooth groove that meshes with the toggle gear is opened on the side of the film carrier plate. The heat-sealing assembly is positioned above the heat-sealing station and is used to heat-seal and fix the food composite film onto the carrier plate of the recycle film assembly. The air tightness and peel performance qualitative testing component is set close to the air tightness and peel performance qualitative testing station and is used to perform air tightness and peel performance qualitative testing on the food composite film heat-sealed on the carrier film plate. The qualitative testing component for compressive strength is positioned above the qualitative testing station for compressive strength and is used to perform qualitative testing on the compressive strength of the food composite film heat-sealed on the carrier film plate.

[0007] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the food composite film is composed of a base layer, a functional layer, and a heat-sealing layer from the outside to the inside. The base layer mainly provides mechanical strength and dimensional stability, and common materials include polyester and nylon. The functional layer gives the composite film specific functions, such as blocking oxygen and water vapor, and commonly used materials include aluminum foil and aluminized film. The heat-sealing layer is used to achieve heat sealing of the film and generally uses materials such as polyethylene and polypropylene.

[0008] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the lower and upper turntables have several radial grooves along their circumferential direction on their mating surfaces. The lower and upper turntables also have testing windows at the radial grooves that match the stepped film carrier hole specifications. Next to the radial grooves, the lower and upper turntables have gear grooves that mate with a gear mechanism. The stepped film carrier hole has a structure that is wider at the top and narrower at the bottom, with the annular stepped surface area serving as the heat-sealing zone of the food composite film. An annular sealing groove is formed around the stepped film carrier hole on the lower side of the film carrier plate, and the material of the film carrier plate is the same as that of the object to be packaged.

[0009] Furthermore, in the above-mentioned heat-sealing performance testing system for food composite films, the heat-sealing assembly includes a heat-sealing substrate, a lifting push rod, a mounting plate, and an annular heat-sealing pressure plate. The heat-sealing substrate is supported by the lifting push rod and the mounting plate is supported by the mounting plate. An annular heat-sealing pressure plate that matches the specifications of the heat-sealing area is installed on the lower side of the mounting plate.

[0010] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the airtightness and peel performance qualitative testing component includes a vertical substrate, a horizontal push rod, a grooved carrier plate, a first lead screw motor, a first lead screw, an airtightness performance qualitative testing mechanism, a second lead screw motor, a second lead screw, and a peel performance qualitative testing mechanism. The vertical substrate is supported by the grooved carrier plate via the horizontal push rod. The first lead screw motor is mounted on the lower side plate of the grooved carrier plate, and a first lead screw is mounted on the output end of the first lead screw motor. The airtightness performance qualitative testing mechanism is sleeved on the outer side of the first lead screw. The second lead screw motor is mounted on the upper side plate of the grooved carrier plate, and a second lead screw is mounted on the output end of the second lead screw motor. The peel performance qualitative testing mechanism is sleeved on the outer side of the second lead screw.

[0011] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the airtightness qualitative testing mechanism includes a first carrier plate. The first carrier plate has a screw groove that cooperates with a first screw. One end of the first carrier plate slides against the web of the grooved carrier plate. A sealing protrusion is installed on the inner side of the first carrier plate. The outer end face of the sealing protrusion is provided with an annular sealing protrusion that cooperates with an annular sealing groove. An air pump is installed on the outer side of the first carrier plate. The air outlet of the air pump is connected to the inner cavity of the sealing protrusion via an air inlet pipe. A pressure sensor is embedded in the first carrier plate within the sealing protrusion.

[0012] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the qualitative testing mechanism for peel performance includes a second carrier plate. The second carrier plate has a screw groove that cooperates with a second screw. One end of the second carrier plate slides against the web of the grooved carrier plate. A peeling motor and a gear box are installed on the outer side of the second carrier plate. The output shaft of the peeling motor is connected to a vertical shaft via a steering gear set placed in the gear box. A sliding sleeve is fitted on the lower outer side of the vertical shaft, and a spring is fitted on the middle outer side of the vertical shaft. The two ends of the spring abut against the second carrier plate and the sliding sleeve, respectively. A scraper is installed at the bottom end of the sliding sleeve, and a peeling friction layer is installed on the outer side of the scraper.

[0013] Furthermore, in the aforementioned food composite film heat-sealing performance testing system, the qualitative testing component for compressive strength includes a cylindrical tube, a third lead screw motor, a third lead screw, a guide rod, an electromagnet, a pressure ring, a weight, a hammer rod, and an annular support plate. A third lead screw motor is installed on the outer side of the upper end plate of the cylindrical tube. A third lead screw extending into the inner cavity of the cylindrical tube is installed at the output end of the third lead screw motor. Several guide rods are installed between the upper and lower end plates of the cylindrical tube. An electromagnet is installed at the top of the inner cavity of the cylindrical tube. A pressure ring is installed at the bottom of the inner cavity of the cylindrical tube. A weight and an annular support plate are jointly fitted onto the outer sides of the third lead screw and guide rods. A hammer rod is installed at the bottom end of the weight. A hammer hole that mates with the hammer rod is opened on the lower end plate of the cylindrical tube.

[0014] Furthermore, in the aforementioned heat-sealing performance testing system for food composite films, the electromagnet and the weight each have clearance holes for avoiding the third lead screw and the guide rod. The third lead screw and the guide rod are located within the inner circumference of the pressure ring. The outer diameter of the annular support plate is smaller than the inner diameter of the pressure ring, the inner diameter of the annular support plate is larger than the diameter of the hammer hole, the thickness of the annular support plate is smaller than the thickness of the pressure ring, and the annular support plate has a lead screw groove that mates with the third lead screw and a guide sliding hole that mates with the guide rod.

[0015] This invention also provides a method for testing the heat-sealing performance of a food composite film, based on the aforementioned system for testing the heat-sealing performance of a food composite film, comprising the following steps: S1. Cut the composite film of the food to be tested into round samples of uniform specifications; drive the turntable to rotate through the rotary drive motor and gear meshing transmission, and rotate the empty carrier film plate to the loading station, and lay the sample flat on the stepped carrier film hole heat sealing area of ​​the carrier film plate; drive the carrier film plate to radially align and calibrate by the motor, and then rotate the carrier film plate with the sample to the heat sealing station, and use the heat sealing assembly to perform constant temperature and pressure heat sealing on the heat sealing area of ​​the sample, so that the sample is firmly attached to the carrier film plate. S2. After heat sealing, the sample is rotated to the airtightness and peel performance qualitative testing station with the turntable; the position of the testing mechanism is adjusted by the horizontal push rod so that the airtightness performance qualitative testing mechanism is aligned with the annular sealing groove at the bottom of the carrier film plate; the sealing convex tube is driven by the first lead screw motor to engage with the sealing groove to form a sealed testing chamber; the air pump is started to inflate the chamber to the preset air pressure and then turned off; the pressure sensor monitors the air pressure change in real time within the preset time period, and the airtightness of the heat-sealed part of the sample is determined according to the air pressure decay; no significant decay means that the airtightness is qualified. S3. After the airtightness test is completed, keep the work position unchanged, and drive the peeling test mechanism to move down through the second lead screw motor so that the scraper friction layer is in contact with the heat-sealed edge of the sample; start the peeling motor, and drive the scraper to horizontally reciprocate to peel off the heat-sealed edge through gear transmission, and rely on the spring to achieve elastic pressing and adhesion; by observing whether the heat-sealed edge shows delamination, cracking or falling off, the peel resistance performance of the heat-sealed structure is qualitatively determined. If there is no damage during peeling, the performance is qualified. S4. After the peel test is completed, the sample is transferred to the compression test station. The ring support plate is moved up by the third lead screw motor, and the weight moves up with it. The weight is fixed by electromagnet adsorption. Then the ring support plate is moved down to hide inside the pressure ring. The electromagnet is de-energized, and the weight falls freely, causing the hammer to vertically impact the heat-sealed area of ​​the sample. After the impact, observe whether there are any problems such as cracking, desealing, or air leakage at the heat-sealed area to determine the compression resistance of the sample after heat sealing. S5. After all test items for a single sample are completed, each test component is reset and the sample is transferred to the unloading station. The carrier film plate is moved radially outward by the motor to remove the tested sample, thus completing a single test process.

[0016] The beneficial effects of this invention are: 1. This invention innovatively integrates qualitative testing of airtightness, qualitative testing of peel resistance, and qualitative testing of compressive strength into a single testing system. Utilizing the multi-station rotating design of the reusable film assembly, it can sequentially complete the entire process of sample loading, heat sealing, multi-item testing, and unloading. Compared to the cumbersome operation of traditional testing equipment that requires multiple equipment changes, repeated sample clamping, and repeated parameter adjustments, this invention eliminates the need for secondary clamping and equipment switching. A single clamping operation can complete all three performance tests, greatly simplifying the testing process, effectively shortening testing time, and significantly improving the overall testing efficiency of the heat-sealing performance of food composite films. This meets the needs of enterprises for batch quality inspection and rapid process verification.

[0017] 2. This invention, by setting the material of the carrier film to be consistent with the material of the object to be packaged, can simulate the actual heat-sealing conditions of food composite films with different packaging containers, and realize the heat-sealing performance testing of differentiated materials. It can realistically reproduce the heat-sealing stability of composite films under different packaging scenarios, making the test results more consistent with actual production and food packaging applications, and providing data support for composite film material selection and heat-sealing process optimization.

[0018] Of course, any product implementing this invention does not necessarily need to achieve all of the above advantages at the same time. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the recirculating membrane assembly in this invention; Figure 3 This is a half-sectional schematic diagram of the recirculating membrane assembly in this invention; Figure 4 This is a schematic diagram of the structure of the carrier film plate at one angle in this invention; Figure 5 This is a schematic diagram of the carrier film plate from another angle in this invention; Figure 6 This is a schematic diagram of the structure of the lower and upper turntables in this invention; Figure 7 This is a schematic diagram of the heat-sealing assembly in this invention; Figure 8 This is a schematic diagram of the airtightness and peeling performance qualitative testing component in this invention; Figure 9 This is a schematic diagram of the airtightness qualitative testing mechanism in this invention; Figure 10 This is a front view schematic diagram of the airtightness performance qualitative testing mechanism in this invention; Figure 11 This is a schematic diagram of the structure of the qualitative testing mechanism for peel performance in this invention; Figure 12 This is a front view schematic diagram of the qualitative testing mechanism for peel performance in this invention; Figure 13 This is a schematic diagram of the structure of the qualitative testing component for compressive strength in this invention; In the attached diagram, the components represented by each number are as follows: 1-Return film transfer assembly, 101-Return base plate, 102-Fixed support tube, 103-Modible support tube, 104-Rotary locking structure, 105-Lower turntable, 106-Upper turntable, 107-Return drive motor, 108-Drive gear, 109-Return tooth groove, 110-Carrier film plate, 111-Stepped carrier film hole, 112-Actuating tooth groove, 113-Actuating motor, 114-Actuating gear, 115-Radial slide groove, 116-Detection window, 117-Gear groove, 118-Annular sealing groove; 2-Heat-sealing assembly, 201-Heat-sealing substrate, 202-Lifting push rod, 203-Mounting plate, 204-Annular heat-sealing pressure plate; 3-Qualitative testing component for air tightness and peel performance; 31-Vertical substrate; 32-Horizontal push rod; 33-Slotted carrier plate; 34-First lead screw motor; 35-First lead screw; 36-Qualitative testing mechanism for air tightness; 361-First carrier plate; 362-Sealing protrusion; 363-Annular sealing protrusion; 364-Air pump; 365-Air inflator; 366-Pressure sensor; 37-Second lead screw motor; 38-Second lead screw; 39-Qualitative testing mechanism for peel performance; 391-Second carrier plate; 392-Peeling motor; 393-Gear box; 394-Vertical shaft; 395-Sliding sleeve; 396-Spring; 397-Scraper; 398-Peeling friction layer; 4-Qualitative testing components for compressive strength, 401-Cylindrical cylinder, 402-Third lead screw motor, 403-Third lead screw, 404-Guide rod, 405-Electromagnet, 406-Pressure ring, 407-Weight block, 408-Hammer rod, 409-Annular support plate, 410-Hammer hole; 5-Food composite film. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figure 1 As shown, this embodiment provides a heat-sealing performance testing system for food composite films, including a reusable film loading assembly 1, a heat-sealing assembly 2, an airtightness and peel performance qualitative testing assembly 3, and a compressive strength qualitative testing assembly 4. The reusable film loading assembly 1 is circumferentially equipped with a feeding station, a heat-sealing station, an airtightness and peel performance qualitative testing station, a compressive strength qualitative testing station, and a feeding station. The heat-sealing assembly 2 is positioned above the heat-sealing station and is used to heat-seal and fix the food composite film 5 onto the film carrier plate of the reusable film loading assembly 1. The airtightness and peel performance qualitative testing assembly 3 is positioned near the airtightness and peel performance qualitative testing station and is used to perform airtightness and peel performance qualitative testing on the food composite film 5 heat-sealed on the film carrier plate. The compressive strength qualitative testing assembly 4 is positioned above the compressive strength qualitative testing station and is used to perform compressive strength qualitative testing on the food composite film 5 heat-sealed on the film carrier plate.

[0023] In this embodiment, the food composite film 5 is composed of a base layer, a functional layer and a heat-sealing layer from the outside to the inside. The base layer mainly provides mechanical strength and dimensional stability, and common materials include polyester and nylon. The functional layer gives the composite film specific functions, such as blocking oxygen and water vapor, and commonly used materials include aluminum foil and aluminized film. The heat-sealing layer is used to achieve heat sealing of the film and generally uses materials such as polyethylene and polypropylene.

[0024] like Figures 2-6 As shown, the recirculating film transfer assembly 1 includes a rotating base plate 101, a fixed support tube 102, a movable support tube 103, a lower turntable 105, an upper turntable 106, a rotating drive motor 107, a drive gear 108, a film carrier plate 110, a toggle motor 113, and a toggle gear 114. The movable support tube 103 is movably supported on the upper side of the rotating base plate 101 via the fixed support tube 102, and a rotating engagement structure 104 is formed between the fixed support tube 102 and the movable support tube 103. A rotary drive motor 107 is mounted on the upper side of the rotary base plate 101. A drive gear 108 is mounted on the output end of the rotary drive motor 107. A rotary tooth groove 109 that meshes with the drive gear 108 is opened on the inner side of the movable support tube 103. A lower turntable 105 is fixed to the upper end of the movable support tube 103. An upper turntable 106 is mounted on the upper side of the lower turntable 105. The lower turntable 105 and the upper turntable 106 together clamp and restrict several carrier film plates 110 that can be radially displaced. A toggle motor 113 is mounted on the lower side of the lower turntable 105. A toggle gear 114 is mounted on the output end of the toggle motor 113. A stepped carrier film hole 111 is opened on the carrier film plate 110 to facilitate receiving the food composite film 5. A toggle tooth groove 112 that meshes with the toggle gear 114 is opened on the side of the carrier film plate 110.

[0025] In this embodiment, the lower turntable 105 and the upper turntable 106 are provided with a plurality of radial grooves 115 along the circumferential direction on the mating surface. The lower turntable 105 and the upper turntable 106 are provided with detection windows 116 at the radial grooves 115 that match the specifications of the stepped film-carrying holes 111. The lower turntable 105 and the upper turntable 106 are provided with gear grooves 117 next to the radial grooves 115 that match the actuating gear 114.

[0026] In this embodiment, the stepped carrier film hole 111 has a structure that is wider at the top and narrower at the bottom, and the annular stepped surface area serves as the heat-sealing area of ​​the food composite film; an annular sealing groove 118 is provided on the lower side of the carrier film plate 110 around the stepped carrier film hole 111, and the material of the carrier film plate 110 is the same as the material of the object to be packaged.

[0027] The recirculating film transfer assembly 1 is the system's transfer and support component, mainly realizing the switching, alignment, and stable support of the sample, providing basic support for each process operation. Its working principle is as follows: the rotating base plate 101 and the fixed support tube 102 form an integral fixed support structure. The fixed support tube 102 movably supports the stably rotatable moving support tube 103. The rotating drive motor 107 drives the drive gear 108 to rotate. Through the meshing transmission between the drive gear 108 and the rotating tooth groove 109 on the inner side of the moving support tube 103, the moving support tube 103 and the lower turntable 105 and upper turntable 106 fixed at the top are driven to rotate circumferentially, realizing the automatic rotation and switching of the film transfer plate 110 between multiple stations such as loading, heat sealing, testing, and unloading; the lower turntable 105 and upper turntable 106... The 6 components clamp each other to form a limiting structure. The radial groove 115 on the mating surface provides a radial sliding trajectory for the carrier plate 110. The actuating motor 113 drives the actuating gear 114 to rotate. Through the meshing transmission between the actuating gear 114 and the actuating tooth groove 112 on the side of the carrier plate 110, the carrier plate 110 is driven to move radially, completing the sample alignment calibration and disassembly avoidance. The stepped carrier hole 111 of the carrier plate 110, which is wider at the top and narrower at the bottom, can limit the heat sealing range of the composite film. The bottom annular sealing groove 118 can be docked with the airtightness testing mechanism to form a sealed testing space. The carrier plate 110 can be replaced with different materials to simulate various packaging container conditions. The testing window 116 on the turntable can avoid structural obstruction and ensure the smooth operation of each process.

[0028] like Figure 7 As shown, the heat sealing assembly 2 includes a heat sealing substrate 201, a lifting push rod 202, a mounting plate 203, and an annular heat sealing pressure plate 204. The heat sealing substrate 201 is supported by the mounting plate 203 via the lifting push rod 202, and an annular heat sealing pressure plate 204 that matches the specifications of the heat sealing area is installed on the lower side of the mounting plate 203.

[0029] The heat-sealing assembly 2 is used to heat-seal and fix the food composite film sample onto the carrier plate 110 at a constant temperature and pressure, simulating the actual production heat-sealing process to prepare standardized test samples. Its working principle is as follows: the heat-sealing substrate 201 is a fixed support base, and the lifting push rod 202 is a power component that can drive the mounting plate 203 and the annular heat-sealing pressure plate 204 at the bottom to rise and fall vertically. When the carrier plate 110 carrying the sample moves to the heat-sealing station, the lifting push rod 202 extends and drives the annular heat-sealing pressure plate 204 to press against the annular stepped heat-sealing area of ​​the carrier plate 110. The composite film heat-sealing operation is completed based on the preset constant temperature and pressure parameters of the equipment, so that the composite film heat-sealing layer is firmly bonded to the carrier plate 110, ensuring that the heat-sealing temperature, pressure and area parameters of each group of samples are uniform, eliminating the interference of process differences on the test results. After the heat-sealing is completed, the lifting push rod 202 is reset, waiting for the next station to move on to the next operation.

[0030] like Figure 8As shown, the airtightness and peel performance qualitative testing assembly 3 includes a vertical base plate 31, a horizontal push rod 32, a grooved carrier plate 33, a first lead screw motor 34, a first lead screw 35, an airtightness performance qualitative testing mechanism 36, a second lead screw motor 37, a second lead screw 38, and a peel performance qualitative testing mechanism 39. The vertical base plate 31 is supported by the grooved carrier plate 33 via the horizontal push rod 32. The first lead screw motor 34 is mounted on the lower side plate of the grooved carrier plate 33, and the first lead screw 35 is mounted on the output end of the first lead screw motor 34. The airtightness performance qualitative testing mechanism 36 is sleeved on the outer side of the first lead screw 35. The second lead screw motor 37 is mounted on the upper side plate of the grooved carrier plate 33, and the second lead screw 38 is mounted on the output end of the second lead screw motor 37. The peel performance qualitative testing mechanism 39 is sleeved on the outer side of the second lead screw 38.

[0031] like Figures 9-10 As shown, the airtightness performance qualitative testing mechanism 36 includes a first carrier plate 361. The first carrier plate 361 has a screw groove that mates with a first screw 35. One end of the first carrier plate 361 slides against the web of the grooved carrier plate 33. A sealing protrusion 362 is installed on the inner side of the first carrier plate 361. The outer end face of the sealing protrusion 362 has an annular sealing protrusion 363 that mates with an annular sealing groove 118. An air pump 364 is installed on the outer side of the first carrier plate 361. The air outlet of the air pump 364 is connected to the inner cavity of the sealing protrusion 362 via an air inlet pipe 365. A pressure sensor 366 is embedded in the first carrier plate 361 within the sealing protrusion 362.

[0032] like Figures 11-12 As shown, the qualitative testing mechanism 39 for peel performance includes a second carrier plate 391. The second carrier plate 391 has a screw groove that cooperates with the second screw 38. One end of the second carrier plate 391 slides against the web of the grooved carrier plate 33. A peeling motor 392 and a gear box 393 are installed on the outer side of the second carrier plate 391. The output shaft of the peeling motor 392 is connected to the vertical shaft 394 via a steering gear set placed in the gear box 393. A sliding sleeve 395 is sleeved on the lower outer side of the vertical shaft 394, and a spring 396 is sleeved on the middle outer side of the vertical shaft 394. The two ends of the spring 396 abut against the second carrier plate 391 and the sliding sleeve 395, respectively. A scraper 397 is installed at the bottom end of the sliding sleeve 395, and a peeling friction layer 398 is installed on the outer side of the scraper 397.

[0033] The airtightness and peel resistance qualitative testing component 3 integrates airtightness and peel resistance testing functions, enabling the completion of two qualitative performance tests at the same workstation without sample change. Its working principle is as follows: the vertical substrate 31 serves as a fixed base, and the horizontal push rod 32 drives the entire grooved carrier plate 33 to move horizontally, aligning the testing mechanism with the carrier film plate 110 and eliminating workstation deviations; the first lead screw motor 34 and the first lead screw 35 on the lower side of the grooved carrier plate 33 drive the airtightness qualitative testing mechanism 36 to move vertically, causing the annular sealing protrusion 363 at the end of the sealing protrusion 362 on the first carrier plate 361 to engage with and embed into the annular sealing groove 118 of the carrier film plate 110, forming a sealed testing chamber. The air pump 364 inflates the chamber to a preset pressure through the air inflator 365 and then stops. The pressure sensor 366 then... The air pressure decay is monitored over a preset time period to qualitatively determine whether the air tightness of the composite film heat seal is up to standard. After the air tightness test is completed, the second lead screw motor 37 and the second lead screw 38 on the upper side of the grooved carrier plate 33 drive the peel performance qualitative test mechanism 39 to move down, so that the peel friction layer 398 on the outer side of the scraper 397 at the bottom of the second carrier plate 391 adheres to the heat seal edge of the composite film. The peel motor 392 drives the vertical shaft 394 and the sliding sleeve 395 through the steering gear set inside the gear box 393 to drive the scraper 397 to horizontally reciprocate and rub peel. The spring 396 continuously provides elastic clamping force to ensure the adhesion stability. By observing whether there are defects such as delamination, cracking, or falling off at the heat seal edge, it can be qualitatively determined whether the peel resistance performance of the heat seal structure meets the standard. The two test mechanisms are driven independently and do not interfere with each other.

[0034] like Figure 13 As shown, the qualitative testing component 4 for compressive strength includes a cylindrical cylinder 401, a third lead screw motor 402, a third lead screw 403, guide rods 404, an electromagnet 405, a pressure ring 406, a weight 407, a hammer rod 408, and an annular support plate 409. The third lead screw motor 402 is mounted on the outer side of the upper end plate of the cylindrical cylinder 401. The output end of the third lead screw motor 402 is fitted with a third lead screw 403 that extends into the inner cavity of the cylindrical cylinder 401. Several guide rods 404 are installed between the upper and lower end plates of the cylindrical cylinder 401. An electromagnet 405 is installed at the top of the inner cavity of the cylindrical tube 401, and a pressure ring 406 is installed at the bottom of the inner cavity of the cylindrical tube 401. A weight 407 and an annular support plate 409 are sleeved on the outer side of the third lead screw 403 and the guide rod 404. A hammer rod 408 is installed at the bottom end of the weight 407, and a hammer hole 410 that mates with the hammer rod 408 is opened on the lower end plate of the cylindrical tube 401.

[0035] In this embodiment, the electromagnet 405 and the weight 407 each have clearance holes for avoiding the third lead screw 403 and the guide rod 404. The third lead screw 403 and the guide rod 404 are located within the inner circumference of the pressure ring 406. The outer diameter of the annular support plate 409 is smaller than the inner diameter of the pressure ring 406, the inner diameter of the annular support plate 409 is larger than the diameter of the hammer hole 410, the thickness of the annular support plate 409 is smaller than the thickness of the pressure ring 406, and the annular support plate 409 has a lead screw groove that mates with the third lead screw 403 and a guide sliding hole that mates with the guide rod 404.

[0036] The pressure resistance qualitative testing component 4 simulates packaging and storage impact loads through controlled free-fall impact to test the pressure resistance of the composite film heat-sealing structure. Its working principle is as follows: the cylindrical cylinder 401 serves as the overall protective support base; the third lead screw motor 402, the third lead screw 403, and the guide rod 404 form a lifting and adjusting structure. In the initial state, it can drive the annular support plate 409 and the weight 407 to move smoothly upwards, causing the weight 407 to be attracted and fixed by the electromagnet 405 at the top of the inner cavity of the cylindrical cylinder 401, completing the impact force storage; after the force storage is completed, the third lead screw motor 402 reverses... Driven by the upward movement, the annular support plate 409 moves downward and hides inside the pressure ring 406, releasing the support and limiting position of the weight 407. Subsequently, the electromagnet 405 is de-energized and loses its magnetism, and the weight 407 falls vertically and freely along the guide rod 404, driving the bottom hammer rod 408 through the hammer hole 410 of the lower end plate of the cylindrical tube 401, and vertically impacting the heat-sealing area of ​​the composite film. By observing whether there are problems such as cracking, desealing, damage, or air leakage at the heat-sealed area, it is qualitatively determined whether the compressive strength of the composite film after heat sealing meets the standard. The guide rod 404 limits and guides throughout the entire process, effectively avoiding detection errors caused by impact deviation.

[0037] This embodiment also provides a method for testing the heat-sealing performance of a food composite film, including the following steps: S1. Select the food composite film 5 to be tested, cut it into uniform circular samples, start the rotary drive motor 107, and drive the dynamic support tube 103, lower turntable 105, and upper turntable 106 to rotate through the meshing of the drive gear 108 and the rotary tooth groove 109, rotating the empty carrier plate 110 to the loading station; place the food composite film 5 sample flat on the stepped heat sealing area of ​​the stepped carrier plate hole 111, and then start the actuation motor 113. The carrier plate 110 is driven to move inward along the radial groove 115 by the gear 114, so that the stepped carrier hole 111 of the carrier plate 110 is aligned with the loading reference position; the rotary drive motor 107 is started again, driving the carrier plate 110 loaded with the sample to rotate to the heat sealing station, and the annular stepped heat sealing area of ​​the stepped carrier hole 111 is subjected to constant temperature and constant pressure heat sealing treatment by the heat sealing assembly 2, so that the food composite film 5 is stably heat-sealed and bonded to the carrier plate 110. S2. After heat sealing, the return film assembly 1 drives the sample to the airtightness and peel performance qualitative testing station. First, the horizontal push rod 32 is started to push the grooved carrier plate 33 to move, so that the airtightness performance qualitative testing mechanism 36 is aligned with the annular sealing groove 118 at the bottom of the carrier plate 110. The first lead screw motor 34 drives the first lead screw 35 to rotate, which drives the first carrier plate 361 to move vertically, so that the annular sealing protrusion 363 of the sealing protrusion tube 362 is engaged and embedded in the annular sealing groove 118 to form a sealed testing cavity. Then, the air pump 364 is started to inflate the sealing protrusion tube 362 and the inside of the composite film. After reaching the preset air pressure, the air pump 364 is turned off. The pressure sensor 366 collects the air pressure value in the cavity in real time and continuously monitors the preset testing time. The airtightness of the composite film heat seal is qualitatively judged according to the amount of air pressure attenuation. If there is no obvious air pressure attenuation, the airtightness is judged to be qualified; otherwise, the airtightness is judged to be defective. S3. After the airtightness test is completed, keep the sample position unchanged, start the second lead screw motor 37 to drive the second lead screw 38 to rotate, and drive the second carrier plate 391 to move vertically downward, so that the peeling friction layer 398 of the scraper 397 adheres to the heat-sealed edge area of ​​the food composite film 5; start the peeling motor 392, and drive the vertical shaft 394 through the steering gear set and gear box 393 to drive the sliding sleeve 395 and scraper 397 to move horizontally back and forth. With the elastic pressing action of the spring 396, the peeling friction layer 398 continuously rubs and peels the heat-sealed edge of the composite film. By observing whether the heat-sealed edge shows delamination, cracking, peeling and falling off, the peel resistance of the composite film heat-sealed structure is qualitatively determined. If there is no peeling damage, the peel resistance is qualified. S4. After the peel test is completed, the retractable film assembly 1 rotates the tested sample to the qualitative test station for compressive strength. The third lead screw motor 402 drives the third lead screw 403 to rotate, causing the annular support plate 409 and the weight 407 to move vertically upward along the guide rod 404. The electromagnet 405 is energized to attract and fix the weight 407. Then, the third lead screw motor 402 drives the third lead screw 403 to rotate in the opposite direction, causing the annular support plate 409 to move downward and be hidden inside the pressure ring 406. The electromagnet 405 is de-energized, the weight 407 is released from the attraction and falls freely along the guide rod 404, causing the hammer rod 408 to pass through the hammer hole 410 and vertically impact the heat-sealed area of ​​the food composite film 5. After the impact, observe whether there is cracking, air leakage, damage, or desealing at the heat-sealed area of ​​the composite film to qualitatively determine the compressive strength of the composite film after heat sealing. S5. After all the test items of a single sample are completed, each test component is reset, the return film assembly 1 drives the sample to the unloading station, the toggle motor 113 is started, and the toggle gear 114 drives the film plate 110 to move outward along the radial slide groove 115 to remove the tested sample.

[0038] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A heat-sealing performance testing system for food composite films, characterized in that, It includes a reusable film assembly, a heat sealing assembly, a qualitative testing assembly for air tightness and peel performance, and a qualitative testing assembly for compressive strength. The reusable film assembly is provided with a feeding station, a heat sealing station, a qualitative testing station for air tightness and peel performance, a qualitative testing station for compressive strength, and a discharging station along the circumferential direction. The recirculating film loading assembly includes a rotating base plate, a fixed support tube, a movable support tube, a lower turntable, an upper turntable, a rotating drive motor, a drive gear, a film carrier plate, a toggle motor, and a toggle gear. The movable support tube is movably supported on the upper side of the rotating base plate via the fixed support tube. The rotating drive motor is mounted on the upper side of the rotating base plate, and a drive gear is mounted on the output end of the rotating drive motor. A rotating tooth groove that meshes with the drive gear is opened on the inner side of the movable support tube. The lower turntable is fixed to the upper end of the movable support tube. The upper turntable is mounted on the upper side of the lower turntable, and together with the upper turntable, several film carrier plates capable of radial displacement are clamped and restricted. The toggle motor is mounted on the lower side of the lower turntable, and a toggle gear is mounted on the output end of the toggle motor. The film carrier plate has stepped film carrier holes for easy reception of food composite film, and a toggle tooth groove that meshes with the toggle gear is opened on the side of the film carrier plate. The heat-sealing assembly is positioned above the heat-sealing station and is used to heat-seal and fix the food composite film onto the carrier plate of the recycle film assembly. The airtightness and peel performance qualitative testing component is located near the airtightness and peel performance qualitative testing station and is used to perform airtightness and peel performance qualitative testing on the food composite film heat-sealed on the carrier film plate. The airtightness and peel performance qualitative testing component includes a vertical base plate, a horizontal push rod, a grooved carrier plate, a first lead screw motor, a first lead screw, an airtightness performance qualitative testing mechanism, a second lead screw motor, a second lead screw, and a peel performance qualitative testing mechanism. The vertical base plate is supported by the horizontal push rod on the grooved carrier plate. The first lead screw motor is installed on the lower side plate of the grooved carrier plate. The first lead screw motor is installed at the output end of the first lead screw motor. The airtightness performance qualitative testing mechanism is sleeved on the outside of the first lead screw. The second lead screw motor is installed on the upper side plate of the grooved carrier plate. The second lead screw motor is installed at the output end of the second lead screw motor. The peel performance qualitative testing mechanism is sleeved on the outside of the second lead screw. The qualitative testing component for compressive strength is positioned above the qualitative testing station for compressive strength and is used to perform qualitative testing on the compressive strength of the food composite film heat-sealed on the carrier film plate.

2. The heat-sealing performance testing system for a food composite film according to claim 1, characterized in that, The food composite film consists of a base layer, a functional layer, and a heat-sealing layer from the outside to the inside.

3. The heat-sealing performance testing system for a food composite film according to claim 2, characterized in that, The lower and upper turntables have several radial grooves along their circumferential surfaces at their mating surfaces. The lower and upper turntables also have inspection windows at the radial grooves that mate with the stepped carrier film aperture specifications. Next to the radial grooves, the lower and upper turntables have gear grooves that mate with the actuating gear. The stepped carrier film aperture has a structure that is wider at the top and narrower at the bottom, with the annular stepped surface area serving as the heat-sealing zone for the food composite film. An annular sealing groove is formed around the stepped carrier film aperture on the lower side of the carrier plate. The material of the carrier plate is the same as that of the object to be packaged.

4. The heat-sealing performance testing system for a food composite film according to claim 3, characterized in that, The heat sealing assembly includes a heat sealing substrate, a lifting push rod, a mounting plate, and an annular heat sealing pressure plate. The heat sealing substrate is supported by the lifting push rod and the mounting plate is mounted on the lower side of the mounting plate. An annular heat sealing pressure plate that matches the specifications of the heat sealing area is mounted on the lower side of the mounting plate.

5. The heat-sealing performance testing system for a food composite film according to claim 4, characterized in that, The airtightness performance qualitative testing mechanism includes a first carrier plate, which has a screw groove that cooperates with a first screw. One end of the first carrier plate slides against the web of the grooved carrier plate. A sealing protrusion is installed on the inner side of the first carrier plate. The outer end face of the sealing protrusion is provided with an annular sealing protrusion that cooperates with an annular sealing groove. An air pump is installed on the outer side of the first carrier plate. The air outlet of the air pump is connected to the inner cavity of the sealing protrusion through an air inlet pipe. A pressure sensor is embedded in the first carrier plate inside the sealing protrusion.

6. The heat-sealing performance testing system for a food composite film according to claim 5, characterized in that, The qualitative testing mechanism for peeling performance includes a second carrier plate with a screw groove that mates with a second screw. One end of the second carrier plate slides against the web of the grooved carrier plate. A peeling motor and a gearbox are mounted on the outer side of the second carrier plate. The output shaft of the peeling motor is connected to a vertical shaft via a steering gear set placed in the gearbox. A sliding sleeve is fitted on the lower outer side of the vertical shaft, and a spring is fitted on the middle outer side of the vertical shaft. The two ends of the spring abut against the second carrier plate and the sliding sleeve, respectively. A scraper is mounted on the bottom end of the sliding sleeve, and a peeling friction layer is mounted on the outer side of the scraper.

7. The heat-sealing performance testing system for a food composite film according to claim 6, characterized in that, The qualitative testing component for compressive strength includes a cylindrical tube, a third lead screw motor, a third lead screw, a guide rod, an electromagnet, a pressure ring, a weight, a hammer rod, and an annular support plate. A third lead screw motor is installed on the outer side of the upper end plate of the cylindrical tube. A third lead screw extending into the inner cavity of the cylindrical tube is installed at the output end of the third lead screw motor. Several guide rods are installed between the upper and lower end plates of the cylindrical tube. An electromagnet is installed at the top of the inner cavity of the cylindrical tube. A pressure ring is installed at the bottom of the inner cavity of the cylindrical tube. A weight and an annular support plate are fitted together on the outer side of the third lead screw and guide rods. A hammer rod is installed at the bottom end of the weight. A hammer hole is formed on the lower end plate of the cylindrical tube to mate with the hammer rod.

8. The heat-sealing performance testing system for a food composite film according to claim 7, characterized in that, The electromagnet and the weight each have clearance holes for avoiding the third lead screw and the guide rod. The third lead screw and the guide rod are located inside the pressure ring. The outer diameter of the annular support plate is smaller than the inner diameter of the pressure ring. The inner diameter of the annular support plate is larger than the diameter of the hammer hole. The thickness of the annular support plate is smaller than the thickness of the pressure ring. The annular support plate has a lead screw groove that mates with the third lead screw and a guide sliding hole that mates with the guide rod.

9. A method for testing the heat-sealing performance of a food composite film, implemented based on the heat-sealing performance testing system for a food composite film as described in claim 8, characterized in that, Includes the following steps: S1. Cut the composite film of the food to be tested into round samples of uniform specifications; drive the turntable to rotate through the rotary drive motor and gear meshing transmission, and rotate the empty carrier film plate to the loading station, and lay the sample flat on the stepped carrier film hole heat sealing area of ​​the carrier film plate; drive the carrier film plate to radially align and calibrate by the motor, and then rotate the carrier film plate with the sample to the heat sealing station, and use the heat sealing assembly to perform constant temperature and pressure heat sealing on the heat sealing area of ​​the sample, so that the sample is firmly attached to the carrier film plate. S2. After heat sealing, the sample is rotated to the airtightness and peel test station by the turntable; the position of the test mechanism is adjusted by the horizontal push rod so that the airtightness performance qualitative test mechanism is aligned with the annular sealing groove at the bottom of the carrier film plate; the sealing convex tube is driven by the first lead screw motor to engage with the sealing groove to form a sealed test chamber; the air pump is started to inflate the chamber to the preset air pressure and then turned off; the pressure sensor monitors the air pressure change in real time within the preset time period, and the airtightness of the heat-sealed part of the sample is determined according to the air pressure decay; no significant decay means that the airtightness is qualified. S3. After the airtightness test is completed, keep the work position unchanged, and drive the peeling test mechanism to move down through the second lead screw motor so that the scraper friction layer is in contact with the heat-sealed edge of the sample; start the peeling motor, and drive the scraper to horizontally reciprocate to peel off the heat-sealed edge through gear transmission, and rely on the spring to achieve elastic pressing and adhesion; by observing whether the heat-sealed edge shows delamination, cracking or falling off, the peel resistance performance of the heat-sealed structure is qualitatively determined. If there is no damage during peeling, the performance is qualified. S4. After the peel test is completed, the sample is transferred to the compression test station. The ring support plate is moved up by the third lead screw motor, and the weight moves up with it. The weight is fixed by electromagnet adsorption. Then the ring support plate is moved down to hide inside the pressure ring. The electromagnet is de-energized, and the weight falls freely, causing the hammer to vertically impact the heat-sealed area of ​​the sample. After the impact, observe whether there are cracks, desealing, or air leakage at the heat-sealed area to determine the compression resistance of the sample after heat sealing. S5. After all test items for a single sample are completed, each test component is reset and the sample is transferred to the unloading station. The carrier film plate is moved radially outward by the motor to remove the tested sample, thus completing a single test process.

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