A food packaging bag heat sealing device

Abstract

The utility model discloses a kind of food packaging bag hot-pressing sealing device, belong to food packaging machinery technical field, by conveying, pre-flattening, negative pressure adsorption, the sequential cooperation of compacting to heat sealing, realize the full automation efficient production of food packaging bag sealing;Its original "pre-flattening-negative pressure adsorption-mechanical compacting" multistage progressive flattening mechanism, can systematically eliminate the macroscopic and microscopic fold of packaging bag, fundamentally ensure the absolute flatness of sealing area, significantly improve sealing quality and product qualification rate;Meanwhile, compacting and heat sealing mechanism share mounting frame and the design that upper heat sealing strip can pass through compacting strip, make equipment layout extremely compact;In addition, the configuration of double conveying belt independent drive also endows the device with stronger adaptability to different products, the utility model has the effect of actively flattening and stably keeping the sealing area of packaging bag before heat sealing, fundamentally eliminates the problem of leakage caused by wrinkle and not tight sealing.

Description

Technical Field

[0001] This utility model belongs to the field of food packaging machinery technology, and more specifically it relates to a heat-sealing device for food packaging bags. Background Technology

[0002] In the food packaging industry, especially for soft, thin plastic or composite film packaging bags, heat sealing is a key process to ensure product airtightness and extend shelf life. In existing technology, common heat sealing devices usually consist of two heat sealing blades (or heat sealing rods), which press the sealing area of ​​the packaging bag together through relative movement, using heat and pressure to fuse them together.

[0003] However, such devices have a significant technical drawback: during the transport and positioning process, the sealing area of ​​flexible packaging bags is highly susceptible to wrinkles due to uneven tension, inaccurate guidance, or the inherent properties of the material. When the wrinkled sealing area enters the hot-pressing station, the upper and lower heat-sealing blades directly press the wrinkles together. Because the wrinkled area consists of multiple layers of material with air gaps, it cannot receive uniform and effective heating and pressure, resulting in insufficient fusion and the formation of microscopic leakage channels. This not only affects the shelf life of food but also easily leads to leakage when packaging liquids or oily foods, causing product quality problems and economic losses. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a heat-sealing device for food packaging bags, which has the advantages of actively flattening and stabilizing the sealing area of ​​the packaging bag before heat sealing, thereby fundamentally eliminating the problems of poor sealing and leakage caused by wrinkles.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A heat sealing device for food packaging bags includes a frame, a conveying mechanism, a pre-flattening mechanism, a pressing mechanism, a negative pressure adsorption mechanism, a heat sealing mechanism, and a control system. The conveying mechanism includes a first conveyor belt and a second conveyor belt arranged parallel to each other along the conveying direction. The two conveyor belts are mounted on the frame through their respective support frames. The first conveyor belt and the second conveyor belt are driven by independent motors one and two, and a heat sealing station gap is formed between them. The pre-flattening mechanism is located above the exit end of the first conveyor belt. It includes a mounting frame, an electric telescopic rod, a mounting plate, a flattening roller, and a motor. The mounting frame is located on the top of the support frame. The electric telescopic rod is located inside the top of the mounting frame. The mounting plate is fixed to the bottom of the output end of the electric telescopic rod. The flattening roller is rotatably connected to the mounting plate through a bearing and is driven by the motor to achieve reverse rotation. The clamping mechanism is located at the gap of the heat sealing station. It includes a second mounting frame, multiple second electric telescopic rods, a clamping strip, and a rectangular hole. The second mounting frame is fixed to the top of the support frame. The multiple second electric telescopic rods are located inside the top of the second mounting frame. The clamping strip is located at the bottom end of the second electric telescopic rod. The rectangular hole is opened in the middle of the clamping strip. The negative pressure adsorption mechanism includes an adsorption strip, which is fixedly installed at the gap of the heat sealing station. A vacuum chamber is opened inside the strip, and several adsorption holes communicating with the vacuum chamber are provided on the top. The vacuum chamber is connected to the negative pressure generator through a pipe. The heat sealing mechanism includes multiple electric telescopic rods, an upper heat sealing strip, and a lower heat sealing seat. The electric telescopic rods are located on the top of the mounting frame and their output ends pass through the top of the mounting frame and are fixedly connected to the upper heat sealing strip. The upper heat sealing strip is located above the pressing strip and its pressing position corresponds to the rectangular hole. The lower heat sealing seat is located at the gap between the heat sealing positions and corresponds to the upper heat sealing strip above it. The control system is electrically connected to motor one, motor two, pre-flattening mechanism, pressing mechanism, negative pressure adsorption mechanism and heat sealing mechanism, and is used to control the sequential operation of each mechanism.

[0006] The advantages of this solution are at least as follows: It achieves full automation of food packaging bag sealing through a sequential process of conveying, pre-flattening, negative pressure adsorption, pressing, and heat sealing, significantly improving production efficiency. It uniquely integrates the "pre-flattening," "negative pressure adsorption," and "pressing" functions in stages and collaboratively before heat sealing. First, the pre-flattening mechanism initially eliminates large-area wrinkles caused by long-distance conveying. Then, the negative pressure adsorption mechanism tightly adsorbs and flattens the packaging bag at the sealing station, precisely eliminating minor wrinkles in the sealing area. Finally, the pressing mechanism provides final fixation. This multi-level, progressive flattening and positioning mechanism fundamentally ensures the absolute flatness of the sealing area, effectively avoiding problems such as missed sealing and incomplete sealing caused by wrinkles, and greatly improving sealing quality and product qualification rate. The pressing mechanism and the heat sealing mechanism share the same mounting frame 2, and the upper heat sealing strip is designed with a rectangular hole that can pass through the pressing strip, making the structure of the entire heat sealing station very compact, reducing the size of the equipment, while ensuring the independence and coordination of the actions of each mechanism. The first and second conveyor belts are driven independently and can be flexibly adjusted to operate synchronously or differentially according to the size and material of the packaging bag, enhancing the adaptability of the device to different products.

[0007] The present invention is further configured such that the rotational linear velocity of the flattening roller driven by the motor is opposite to the conveying direction of the packaging bag, and its rotational linear velocity is greater than the conveying speed of the conveying mechanism.

[0008] The advantages of this scheme are at least as follows: by making the flattening roller rotate in the opposite direction and at high speed, an active frictional force opposite to the conveying direction is applied to the surface of the packaging bag, which can more effectively unfold and smooth out the wrinkles generated during forward conveying. Its flattening effect is far superior to that of passively rotating or co-rotating rollers.

[0009] The present invention is further configured such that a high-temperature resistant elastic layer is provided at the bottom of the pressing strip.

[0010] The advantages of this solution are at least as follows: the high-temperature resistant elastic layer (such as silicone) can adapt to the slight unevenness of the packaging bag surface during compression, forming a good sealing area and preventing air bubbles from forming due to internal air residue during heat sealing. At the same time, its elasticity provides cushioning, preventing excessive compression force from damaging or breaking the soft packaging bag; and because it is adjacent to the upper heat-sealing strip, its high-temperature resistance ensures that the compression strip itself will not be damaged by high temperatures, extending its service life.

[0011] The present invention is further configured such that: a plurality of adsorption holes on the adsorption strip are evenly arranged along its length, and the adsorption holes are conical holes with the larger opening end facing the packaging bag.

[0012] The advantages of this scheme are at least as follows: the uniform arrangement of the adsorption holes ensures the consistent distribution of adsorption force along the entire length of the seal, avoiding wrinkling due to insufficient adsorption force in certain areas; the larger opening of the conical hole can better fit the packaging bag, forming an effective negative pressure sealing area, which improves the reliability and efficiency of adsorption.

[0013] The present invention is further configured such that the surface of the flattening roller is covered with an elastic material layer.

[0014] The advantages of this solution are at least as follows: the elastic material layer (such as rubber) increases the coefficient of friction between the flattening roller and the surface of the packaging bag, ensuring that the reverse rotation can effectively unfold the wrinkles and prevent flattening failure caused by slippage; the elastic material is relatively soft and will not cause scratches or wear to the surface of the packaging bag during high-speed reverse rotation, thus protecting the appearance of the product.

[0015] The present invention is further configured such that: guide rails for lateral positioning of the packaging bag are provided on both sides of the conveying mechanism.

[0016] The advantages of this solution are at least as follows: the guide rails can laterally limit the packaging bags, preventing them from deviating during transport and ensuring that the packaging bags can accurately enter the heat sealing station, making the sealing line uniform and aesthetically pleasing; it reduces poor sealing or equipment jamming caused by positional deviations, and ensures the continuity and stability of the automated production process. Attached Figure Description

[0017] Figure 1This is a schematic diagram of a preferred embodiment of the present invention; Figure 2 This is a three-dimensional sectional view of the present invention; Figure 3 This is a partial cross-sectional view of the structure of this utility model; Figure 4 This is a right-side sectional view of the present invention.

[0018] Reference numerals: 1. Frame; 2. Conveying mechanism; 201. First conveyor belt; 202. Second conveyor belt; 203. Motor 1; 204. Motor 2; 3. Pre-flattening mechanism; 301. Mounting frame 1; 302. Electric telescopic rod 1; 303. Mounting plate; 304. Flattening roller; 305. Motor 3; 4. Pressing mechanism; 401. Mounting frame 2; 402. Electric telescopic rod 2; 403. Pressing strip; 404. Rectangular hole; 5. Negative pressure adsorption mechanism; 51. Adsorption strip; 511. Vacuum chamber; 512. Adsorption hole; 513. Negative pressure generator; 6. Heat sealing mechanism; 601. Electric telescopic rod 3; 602. Upper heat sealing strip; 603. Lower heat sealing seat; 7. Guide rail; 8. Packaging bag. Detailed Implementation

[0019] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the following description, in conjunction with specific illustrations, further elaborates on this utility model.

[0020] A heat-sealing device for food packaging bags, such as Figure 1 As shown, it includes a frame 1, a conveying mechanism 2, a pre-flattening mechanism 3, a pressing mechanism 4, a negative pressure adsorption mechanism 5, a heat sealing mechanism 6, and a control system. The conveying mechanism 2 includes a first conveyor belt 201 and a second conveyor belt 202 arranged parallel to each other along the conveying direction. The two are installed on the frame 1 through their respective support frames. The first conveyor belt 201 and the second conveyor belt 202 are both driven by independent motor 1 203 and motor 204, and a heat sealing station gap is formed between them. The pre-flattening mechanism 3 is located above the exit end of the first conveyor belt 201. It includes a mounting frame 301, an electric telescopic rod 302, a mounting plate 303, a flattening roller 304, and a motor 305. The mounting frame 301 is located on the top of the support frame. The electric telescopic rod 302 is located inside the top of the mounting frame 301. The mounting plate 303 is fixed to the bottom of the output end of the electric telescopic rod 302. The flattening roller 304 is rotatably connected to the mounting plate 303 through a bearing and is driven by the motor 305 to achieve reverse rotation. The clamping mechanism 4 is set at the gap of the heat sealing station. It includes a second mounting frame 401, multiple electric telescopic rods 402, a clamping strip 403 and a rectangular hole 404. The second mounting frame 401 is fixed to the top of the support frame. The multiple electric telescopic rods 402 are set inside the top of the second mounting frame 401. The clamping strip 403 is set at the bottom of the electric telescopic rods 402. A rectangular hole 404 is opened in the middle of the clamping strip 403. The negative pressure adsorption mechanism 5 includes an adsorption strip 51, which is fixedly installed at the gap of the heat sealing station, and has a vacuum chamber 511 inside (see reference). Figure 2 The top is provided with several adsorption holes 512 that communicate with the vacuum chamber 511. The vacuum chamber 511 is connected to the negative pressure generator 513 (see reference) through a pipe. Figure 2 )connect; The heat sealing mechanism 6 includes multiple electric telescopic rods 601, an upper heat sealing strip 602, and a lower heat sealing seat 603. The electric telescopic rods 601 are set on the top of the mounting frame 401 and the output end passes through the top of the mounting frame 401 and is fixedly connected to the upper heat sealing strip 602. The upper heat sealing strip 602 is located above the pressing strip 403, and its pressing position corresponds to the rectangular hole 404. The lower heat sealing seat 603 is set at the gap of the heat sealing position and corresponds to the upper heat sealing strip 602 above it. The control system is electrically connected to motor 1 (203), motor 2 (204), pre-flattening mechanism 3, pressing mechanism 4, negative pressure adsorption mechanism 5, and heat sealing mechanism 6 to control the sequential operation of each mechanism. Through the sequential coordinated operation of conveying, pre-flattening, negative pressure adsorption, pressing, and heat sealing, the fully automated and efficient production of sealing food packaging bags 8 is realized. Its unique multi-stage progressive flattening mechanism of "pre-flattening-negative pressure adsorption-mechanical pressing" can systematically eliminate macroscopic and microscopic wrinkles of packaging bags 8, fundamentally ensuring the absolute flatness of the sealing area and significantly improving sealing quality and product qualification rate. At the same time, the design of the pressing and heat sealing mechanisms 6 sharing the mounting frame and the upper heat sealing strip 602 passing through the pressing strip 403 makes the equipment layout extremely compact. In addition, the configuration of dual conveyor belts with independent drive also gives the device stronger adaptability to different products.

[0021] like Figure 3 As shown, the linear velocity of the flattening roller 304 driven by motor 305 is opposite to the conveying direction of the packaging bag 8, and its linear velocity is greater than the conveying speed of the conveying mechanism 2. By making the flattening roller 304 rotate in the opposite direction and at high speed, an active frictional force opposite to the conveying direction is applied to the surface of the packaging bag 8, which can more effectively unfold and smooth out the wrinkles generated during forward conveying. Its flattening effect is far superior to that of passively rotating or co-rotating rollers.

[0022] like Figure 2As shown, a high-temperature resistant elastic layer is provided at the bottom of the compression strip 403. This high-temperature resistant elastic layer (such as silicone) adapts to minor unevenness on the surface of the packaging bag 8 during compression, forming a good sealing area and preventing air bubbles from forming due to internal air residue during heat sealing. Simultaneously, its elasticity provides cushioning, preventing excessive compression force from damaging or breaking the soft packaging bag 8. Because it is adjacent to the upper heat-sealing strip 602, its high-temperature resistance ensures that the compression strip 403 itself will not be damaged by high temperatures, extending its service life.

[0023] like Figure 2 As shown, several adsorption holes 512 on the adsorption strip 51 are evenly arranged along its length, and the adsorption holes 512 are conical holes with the larger opening facing the packaging bag 8. The even arrangement of the adsorption holes 512 ensures the uniform distribution of adsorption force along the entire sealing length, avoiding wrinkling due to insufficient adsorption force in some areas; the larger opening of the conical hole can better fit with the packaging bag 8, forming an effective negative pressure sealing area, improving the reliability and efficiency of adsorption.

[0024] like Figure 3 As shown, the surface of the flattening roller 304 is covered with an elastic material layer. The elastic material layer (such as rubber) increases the coefficient of friction between the flattening roller 304 and the surface of the packaging bag 8, ensuring that the pleats can be effectively unfolded during reverse rotation and preventing flattening failure caused by slippage; the elastic material is relatively soft and will not cause scratches or wear to the surface of the packaging bag 8 during high-speed reverse rotation, thus protecting the appearance of the product.

[0025] like Figure 1 As shown, guide rails 7 are provided on both sides of the conveying mechanism 2 for lateral positioning of the packaging bag 8. The guide rails 7 can laterally limit the packaging bag 8 to prevent it from deviating during the conveying process, ensuring that the packaging bag 8 can accurately enter the heat sealing station, making the sealing line uniform and beautiful; reducing poor sealing or equipment jamming caused by positional deviation, and ensuring the continuity and stability of the automated production process.

[0026] The working process and beneficial effects of this utility model are as follows: The packaging bag 8 is placed on the first conveyor belt 201 of the conveying mechanism 2 by upstream equipment or manually. Motor 1 203 and Motor 2 204 operate synchronously, driving the first and second conveyor belts 202 to transport the sealing part of the packaging bag 8 to the heat sealing station gap. When the front end of the packaging bag 8 reaches the outlet end of the first conveyor belt 201, the pre-flattening mechanism 3 is activated. The electric telescopic rod 1 302 pushes the mounting plate 303 and the flattening roller 304 down to make them contact the surface of the packaging bag 8. Motor 3 305 drives the flattening roller 304 to rotate in the opposite direction with a faster linear speed. After pre-flattening, the sealing part of the packaging bag 8 is just transported to the position of the adsorption strip 51 above the heat sealing station gap. The negative pressure generator 513 is activated, generating negative pressure in the vacuum chamber 511 inside the adsorption strip 51 through the pipeline. The negative pressure acts on the surface of the packaging bag 8 through the evenly arranged conical adsorption holes 512 at the top, tightly adsorbing it onto the adsorption strip 51. After the packaging bag 8 is fixed by negative pressure adsorption, the pressing mechanism 4 immediately activates, and multiple electric telescopic rods 402 press down synchronously, driving the pressing strip 403 to move downwards. The pressing strip 403 presses onto the packaging bag 8, located on both sides of the future heat-sealing line, forming a reliable sealing contact area with the packaging bag 8 and the supporting surface below. The pressing action helps to expel air from the heat-sealing area and prevent air bubbles from forming inside the seal. After the pressing mechanism 4 has pressed and fixed the packaging bag 8, the heat-sealing mechanism 6 starts to work. Multiple electric telescopic rods 601 drive the upper heat-sealing strip 602 to move downwards. The upper heat-sealing strip 602 precisely passes through the rectangular hole 404 in the middle of the pressing strip 403 and presses down onto the adsorbed and pressed packaging bag 8. The packaging bag 8 is pressed between the upper heat-sealing strip 602 and the lower heat-sealing seat 603, and the heat-sealing is completed under the set temperature, pressure, and time. After the heat sealing time is reached, each mechanism resets in sequence. The electric telescopic rod 3 601 drives the upper heat sealing strip 602 to rise and retract to above the rectangular hole 404. The electric telescopic rod 2 402 drives the pressing strip 403 to rise and release the pressing. The negative pressure generator 513 stops working and the negative pressure adsorption is released. Finally, the motors 1 203 and 204 of the conveying mechanism 2 are restarted, and the sealed packaging bag 8 is sent out of the heat sealing station through the second conveyor belt 202 to enter the next stage.

[0027] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the design concept of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A heat-sealing device for food packaging bags, comprising a frame (1), a conveying mechanism (2), a pre-flattening mechanism (3), a pressing mechanism (4), a negative pressure adsorption mechanism (5), a heat-sealing mechanism (6), and a control system, characterized in that: The conveying mechanism (2) includes a first conveyor belt (201) and a second conveyor belt (202) arranged parallel to each other along the conveying direction. The two are installed on the frame (1) through their respective support frames. The first conveyor belt (201) and the second conveyor belt (202) are both driven by independent motor one (203) and motor two (204), and a heat sealing station gap is formed between them. The pre-flattening mechanism (3) is located above the outlet end of the first conveyor belt (201). It includes a mounting frame (301), an electric telescopic rod (302), a mounting plate (303), a flattening roller (304), and a motor (305). The mounting frame (301) is located on the top of the support frame. The electric telescopic rod (302) is located inside the top of the mounting frame (301). The mounting plate (303) is fixed to the bottom of the output end of the electric telescopic rod (302). The flattening roller (304) is rotatably connected to the mounting plate (303) through a bearing and is driven by the motor (305) to achieve reverse rotation. The pressing mechanism (4) is located at the gap of the heat sealing station. It includes a second mounting frame (401), multiple electric telescopic rods (402), a pressing strip (403), and a rectangular hole (404). The second mounting frame (401) is fixed to the top of the support frame. The multiple electric telescopic rods (402) are located at the top inside the second mounting frame (401). The pressing strip (403) is located at the bottom of the electric telescopic rods (402). The rectangular hole (404) is opened in the middle of the pressing strip (403). The negative pressure adsorption mechanism (5) includes an adsorption strip (51), which is fixedly installed at the gap of the heat sealing station. A vacuum chamber (511) is opened inside it, and several adsorption holes (512) communicating with the vacuum chamber (511) are provided on the top. The vacuum chamber (511) is connected to the negative pressure generator (513) through a pipe. The heat sealing mechanism (6) includes multiple electric telescopic rods (601), an upper heat sealing strip (602), and a lower heat sealing seat (603). The electric telescopic rods (601) are set on the top of the mounting frame (401) and the output end passes through the top of the mounting frame (401) and is fixedly connected to the upper heat sealing strip (602). The upper heat sealing strip (602) is located above the pressing strip (403), and its pressing position corresponds to the rectangular hole (404). The lower heat sealing seat (603) is set at the gap of the heat sealing position and corresponds to the upper heat sealing strip (602) above. The control system is electrically connected to motor one (203), motor two (204), pre-flattening mechanism (3), pressing mechanism (4), negative pressure adsorption mechanism (5) and heat sealing mechanism (6) to control the sequential operation of each mechanism.

2. The heat-sealing device for food packaging bags according to claim 1, characterized in that: The direction of the rotational linear velocity of the flattening roller (304) driven by the motor (305) is opposite to the conveying direction of the packaging bag (8), and its rotational linear velocity is greater than the conveying speed of the conveying mechanism (2).

3. The heat-sealing device for food packaging bags according to claim 1, characterized in that: The bottom of the clamping strip (403) is provided with a high-temperature resistant elastic layer.

4. The heat-sealing device for food packaging bags according to claim 1, characterized in that: The adsorption strip (51) has several adsorption holes (512) evenly arranged along its length, and the adsorption holes (512) are conical holes with the larger opening facing the packaging bag (8).

5. The heat-sealing device for food packaging bags according to claim 1, characterized in that: The surface of the flattening roller (304) is covered with an elastic material layer.

6. The heat-sealing device for food packaging bags according to claim 1, characterized in that: The conveying mechanism (2) is provided with guide rails (7) on both sides for lateral positioning of the packaging bag (8).

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