A three-side sealed microwave exhaust bag and a heat sealing cutter thereof

Abstract

This utility model relates to a three-side-seal microwave venting bag and its heat-sealing tool. The microwave venting bag has a reinforced heat-sealing zone and a weakened heat-sealing zone on the bottom edge. The latter includes an arc-shaped structure protruding into the bag, with a vent formed on the concave side. Stress is dispersed through the cooperation of the guiding zone and the tension-reducing zone, and the heat-sealing width of the vent is reduced by a notch. An easy-tear opening and directional markings are provided on the side for auxiliary use. The heat-sealing tool uses a reinforced heat-sealing zone tool and a weakened heat-sealing zone tool, with their processing areas overlapping at the ends. The tool includes a hollow structure to adapt to the tension-reducing zone, and a multi-curvature arc structure to ensure a gradient in heat-sealing strength. When the bag is microwave-heated, it expands, creating a height difference between the front and rear membranes. Gravity concentrates the contents in the front membrane, causing the weakened heat-sealing zone to fail preferentially as a stress concentration point, achieving directional and efficient venting and reducing the risk of splashing.

Description

Technical Field

[0001] This utility model relates to the field of food packaging technology, specifically to a three-side seal microwave venting bag and its heat sealing tool. Background Technology

[0002] Microwave venting bags are food packaging containers specifically designed for microwave heating. Their core function is to release steam generated during heating through pre-designed venting channels, preventing excessive internal pressure that could cause the packaging to rupture or contents to spill. Traditional microwave venting bags often use a three-side seal structure, where the three edges of the bag are heat-sealed to form a flat bag shape. While this design simplifies the production process and reduces costs, the bag cannot stand upright on its own and must be placed flat inside the microwave oven. However, when the bag is lying flat, the large contact area with the microwave oven platform restricts the steam escape path, easily leading to insufficient venting efficiency or localized overheating. This can cause problems such as contents splashing and spillage, posing safety hazards and affecting heating uniformity.

[0003] Current solutions to the above problems include using other items to help adjust the exhaust path of the microwave exhaust bag. For example, place the microwave exhaust bag in a bowl with the exhaust port facing upwards, and then put the whole thing into the microwave oven for heating.

[0004] The utility model patent application with publication number CN113427872A provides a PP / PE easy-peel film material that can achieve different heat-sealing strengths under different temperature and pressure conditions. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a three-side sealed microwave exhaust bag that can automatically exhaust microwave gas without any assistance.

[0006] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0007] A three-side sealed microwave venting bag is formed by three sides that are integrally connected through heat-sealing areas at the edges and have a receiving cavity. The venting bag includes a front membrane and a rear membrane. The left and right edges of the front membrane overlap with the left and right edges of the rear membrane. A reinforced heat-sealing area is provided between the bottom edge of the venting bag and the left and right sides. A weakened heat-sealing area is provided on the bottom edge of the rear membrane towards the inside of the bag. The weakened heat-sealing area includes an arc shape that protrudes towards the inside of the venting bag, and the concave side of the arc shape is the vent.

[0008] As a preferred technical solution, the enhanced heat-sealing area includes a guide area that extends to the left and right sides along the bottom edge of the front membrane and is inclined.

[0009] As a preferred technical solution, a tension-reducing area is left between the guide area and the corner of the exhaust bag, and the tension-reducing area is a non-heat-sealed area.

[0010] As a preferred technical solution, a notch is provided at the bottom edge connection between the rear membrane and the front membrane, and the notch reduces the width of the heat-sealing area on the exhaust port side.

[0011] As a preferred technical solution, the front and rear films are provided with easy-tear openings on the sides away from the bottom heat-sealing area.

[0012] As a preferred technical solution, the rear membrane and / or the front membrane are provided with directional markings.

[0013] For a three-side sealed microwave exhaust bag having any one or more of the above-mentioned technical features, this utility model also provides a heat-sealing tool for the microwave exhaust bag, including a tool for reinforcing the heat-sealing area and a tool for weakening the heat-sealing area. The shapes of the two tools correspond to the reinforcing heat-sealing area and the weakening heat-sealing area, respectively, and the end portions of the processing areas of the tool for reinforcing the heat-sealing area and the tool for weakening the heat-sealing area overlap.

[0014] As a preferred technical solution, the tool for the enhanced heat-sealing zone is an isosceles triangle arranged symmetrically on both sides.

[0015] As a preferred technical solution, the tool in the enhanced heat-sealing zone has a hollow structure that is compatible with the tension-reducing zone.

[0016] As a preferred technical solution, the tool for reducing heat sealing area is arranged symmetrically on both sides and has multiple arc structures with different radii of curvature.

[0017] The advantages and beneficial effects of this utility model are as follows: When the front membrane is placed downward in the microwave oven, the steam generated inside the vent bag during microwave heating causes the vent bag to inflate, creating a height difference between the upper and lower sides of the front and rear membranes. The heat-sealing area at the bottom of the bag has a strength difference, which will act as a stress concentration point and cause heat-sealing failure first, thereby achieving venting. At the same time, since the height difference occurs before heat-sealing failure, the contents are concentrated on the front membrane due to gravity, reducing the risk of contents splashing out of the vent hole during venting.

[0018] This utility model also provides a corresponding heat-sealing tool. The pressure and temperature of the tool in the heat-sealing zone are different from those of the tool in the heat-sealing zone, which makes the exhaust port relatively easy to fail to heat seal. Attached Figure Description

[0019] Figure 1 This is one of the structural schematic diagrams of the microwave exhaust bag of this utility model;

[0020] Figure 2 This is the second schematic diagram of the structure of the microwave exhaust bag of this utility model;

[0021] Figure 3 This is a schematic diagram of the structure of the tool for strengthening the heat-sealing zone of this utility model;

[0022] Figure 4 This is a schematic diagram of the structure of the tool for reducing heat sealing zone according to this utility model;

[0023] Reference numerals: 1-Heat-sealing area, 2-Front membrane, 3-Rear membrane, 4-Reinforced heat-sealing area, 5-Reduced heat-sealing area, 6-Arc shape, 7-Exhaust port, 8-Guiding area, 9-Tension reduction area, 10-Notch, 11-Easy-tear opening, 12-Reinforced heat-sealing area cutter, 13-Reduced heat-sealing area cutter, 14-Hollow structure, 15-Circular arc structure. Detailed Implementation

[0024] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0025] Example 1

[0026] Please see Figures 1-2 This embodiment provides a three-side sealed microwave venting bag, which is formed by three sides enclosing and integrally connected by heat-sealing areas 1 at the edges to form a receiving cavity. The microwave venting bag includes a front membrane 2 and a rear membrane 3, wherein the left and right edges of the front membrane 2 coincide with the left and right edges of the rear membrane 3. A reinforced heat-sealing area 4 is provided between the bottom edge of the bag and the left and right sides. A weakened heat-sealing area 5 is provided on the bottom edge of the rear membrane 3 towards the inside of the bag. The weakened heat-sealing area 5 includes an arc 6 protruding towards the inside of the venting bag, and the concave side of the arc directly forms the vent 7. According to the utility model description, when the bag is in use, the front membrane 2 is placed downwards in the microwave oven. The internal steam causes the bag to inflate, and a height difference is formed between the front membrane 2 and the rear membrane 3. Due to the difference in strength, the weakened heat-sealing area 5 preferentially fails to seal, thus achieving directional venting.

[0027] Example 2

[0028] Based on Example 1, the reinforced heat-sealing area 4 at the bottom of the bag includes guide areas 8 extending to the left and right sides along the bottom edge of the front membrane 2 and arranged at an angle. A tension-reducing area 9 is provided between the guide area 8 and the corner of the venting bag. The tension-reducing area 9 is a non-heat-sealing area to reduce stress concentration. By dispersing the heat-sealing stress through the guide area 8, and using the tension-reducing area 9 as a buffer zone in conjunction with the venting process, it ensures that the height difference of the front membrane 2 occurs preferentially during microwave heating, and the contents are concentrated in the front membrane 2 due to gravity, effectively reducing the risk of venting splashes.

[0029] Example 3

[0030] Based on Example 2, a notch 10 is provided at the bottom edge connection between the rear film 3 and the front film 2. The notch 10 reduces the width of the heat-sealed area on one side of the vent 7 to promote venting failure. An easy-tear opening 11 is provided on the side of the front film 2 and the rear film 3 away from the bottom heat-sealed area to facilitate opening the bag. At the same time, directional markings (such as "this side up") are provided on the rear film 3 or the front film 2 to guide correct placement. By adjusting the heat-sealing strength gradient through the notch 10, combined with the user-friendly feature of the easy-tear opening 11, accurate venting is achieved when the bag stands upright on its own. The directional markings ensure that the user keeps the bag with the vent 7 facing upwards inside the microwave oven during use.

[0031] Example 4

[0032] Please see Figures 3-4 This embodiment provides a heat-sealing tool adapted to embodiments 1-3. The tool includes a reinforcing heat-sealing area tool 12 and a weakening heat-sealing area tool 13, whose shapes correspond to the reinforcing heat-sealing area 4 and the weakening heat-sealing area 5 of the bag body, respectively, and their ends overlap. The reinforcing heat-sealing area tool 12 is an isosceles triangle arranged symmetrically on both sides and has a hollow structure 14 that matches the tension-reducing area 9. The weakening heat-sealing area tool 13 is arranged symmetrically on both sides and has multiple arc structures 15 with different radii of curvature. The reinforcing heat-sealing area tool 12 uses a heat-sealing temperature of 150℃ and a pressure of 0.5MPa, while the weakening heat-sealing area tool 13 uses a hot air temperature of 130℃ and a pressure of 0.3MPa alternately to complete the heat-sealing structure.

[0033] The working principle of this utility model is that the three-side sealed microwave venting bag achieves autonomous venting through a structural heat-sealing strength gradient: when the bag is placed in the microwave oven with the front membrane 2 facing down according to the direction markings, the steam generated by heating causes the bag to inflate. Due to gravity, a height difference is formed between the front membrane 2 and the rear membrane 3. At this time, the weakened heat-sealing zone 5 at the bottom edge fails due to stress concentration, while the strengthened heat-sealing zone 4 maintains structural stability. At the same time, the height difference causes the contents to accumulate on the front membrane 2 under gravity, and the vent 7 directionally discharges steam, avoiding splashing of the contents. The special heat-sealing tool forms the strength gradient during the manufacturing stage through differentiated temperature and pressure control, ensuring reliable venting.

[0034] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A three-seal microwave exhaust bag characterized by, The microwave exhaust bag is formed by three sides enclosing and integrally connected by the heat-sealing area (1) at the edge to form a receiving cavity. The microwave exhaust bag includes a front membrane (2) and a rear membrane (3). The left and right edges of the front membrane (2) coincide with the left and right edges of the rear membrane (3). A reinforced heat-sealing area (4) is provided between the bottom edge and the left and right sides. A weakened heat-sealing area (5) is provided on the bottom edge of the rear membrane (3) towards the inside of the bag. The weakened heat-sealing area (5) includes an arc (6) protruding towards the inside of the exhaust bag. The concave side of the arc forms an exhaust port (7).

2. The three-side-sealed microwave exhaust bag according to claim 1, characterized in that, The enhanced heat-sealing area (4) includes a guide area (8) that extends to the left and right sides along the bottom edge of the front membrane (2) and is inclined.

3. The three-side-sealed microwave exhaust bag according to claim 2, characterized in that, A tension-reducing area (9) is left between the guide area (8) and the corner of the exhaust bag, and the tension-reducing area (9) is a non-heat-sealed area.

4. The three-side-sealed microwave exhaust bag according to claim 2, characterized in that, The rear membrane (3) and the front membrane (2) are connected at the bottom edge with a notch (10), which is used to reduce the width of the heat-sealing area on one side of the exhaust port (7).

5. The three-side-sealed microwave exhaust bag according to claim 2, characterized in that, The front membrane (2) and the rear membrane (3) have easy-tear openings (11) on their sides away from the bottom heat-sealing area.

6. The three-side-sealed microwave exhaust bag according to claim 1, characterized in that, The rear membrane (3) and / or the front membrane (2) are provided with orientation markings.

7. A heat-sealing tool for a three-side-sealed microwave exhaust bag according to any one of claims 1 to 6, characterized in that, It includes a heat-sealing area tool (12) and a heat-sealing area tool (13), the shape of which corresponds to the heat-sealing area (4) of the microwave exhaust bag, and the shape of which corresponds to the heat-sealing area (5), and the end portions of the processing areas of the heat-sealing area tool (12) and the heat-sealing area tool (13) overlap.

8. The heat-sealing tool according to claim 7, characterized in that, The enhanced heat-sealing zone cutter (12) is an isosceles triangle arranged symmetrically on the left and right.

9. The heat-sealing tool according to claim 7, characterized in that, The heat-sealing zone cutter (12) has a hollow structure (14) that is compatible with the tension-reducing zone (9).

10. The heat-sealing tool according to claim 7, characterized in that, The heat-sealing zone weakening tool (13) is arranged symmetrically on the left and right, and has multiple arc structures (15) with different radii of curvature.

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