Plastic bag production equipment based on multi-point concentrated hot melting process

Abstract

According to the plastic bag production equipment based on the multi-point concentrated hot melting technology, by arranging a roller-shaped heat sealing cutter, when air cylinders drive the heat sealing cutter to move downwards, only a small part of the area of the bottom of the roller-shaped heat sealing cutter makes contact with a plastic bag, and the other air cylinder drives the heat sealing cutter to do horizontal linear motion; and the intelligent control motor drives the heat sealing cutter to roll, so that the roller-shaped heat sealing cutter linearly moves to extrude the plastic bag and rolls to extrude the plastic bag at the same time, air in the plastic bag is pressed away, and the amount of bubbles at the heat sealing position of the plastic bag is reduced. Meanwhile, the arc-shaped electric heating plate is arranged at the bottom of the roller-shaped heat sealing cutter, the electric heating plate only heats the part, about to be in rolling contact with the plastic bag, of the heat sealing cutter, the part, away from the electric heating plate in a rolling mode, of the heat sealing cutter does not make close contact with the electric heating plate any more, and the heat sealing cutter is not in a high-heat state for a long time; and the heat-sealing cutter is not in a low-temperature state with large temperature difference even under the influence of internal hot air, so that the service life of the heat-sealing cutter is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of plastic production, and in particular to a plastic bag production device based on a multi-point centralized hot-melt process. Background Art

[0002] In the process of producing and processing plastic bags, it is necessary to use a multi-point centralized hot-melt device to process the parts of the plastic bags that need hot-melt welding. The main method is to set up a frame according to the parts of the plastic bags that need hot-melt welding, and bolt a heat-sealing knife on the frame. The plastic bags that have not been cut are transported through a conveyor so that the part of the plastic bag to be welded is moved to the bottom of the heat-sealing knife. The heat-sealing knife is pushed down by the cylinder above the heat-sealing knife so that the bottom end of the heat-sealing knife is squeezed on the plastic bag, and the plastic bag is quickly hot-melt welded. Then, the cylinder is pulled up by the cylinder, and the plastic bag is transported to the bottom of the next heat-sealing knife through the conveyor.

[0003] During this process, the heat sealing knife is quickly heated to the hot melt temperature (the specific temperature is adjusted according to actual needs, generally between 120 and 150 degrees) by an electric heating device such as an internally connected electric heating tube, and the contact time with the plastic bag is about one to three seconds. The bottom end of the existing heat sealing knife is mostly a flat structure, which means that when the heat sealing knife presses down the plastic bag, the entire bottom surface is pressed on the plastic bag at the same time, which can easily lead to the air trapped between the plastic bags being unable to be discharged, resulting in bubbles of different sizes appearing in the heat-sealed area. The wider the heat seal, the denser the bubbles.

[0004] After the heat sealing knife melts the plastic bag, it needs to wait for the hot-melt plastic tape to cool down and solidify. If the heat sealing knife is lifted up to allow the hot-melt part to contact the air for natural cooling and solidification, the required cooling time will be longer, especially in the case of large-area heat sealing. This natural cooling time will be further increased. If an external cooling air system is used for cooling, a large number of air cooling equipment will be required, which will increase the cost. Both of these methods will keep the heat sealing knife in a continuous high temperature state, which will undoubtedly shorten the service life of the heat sealing knife. Some high-precision heat sealing knives have built-in liquid cooling systems. After the heat sealing is completed, the liquid cooling system is started to quickly cool the heat sealing knife, and this cooling is transmitted to the plastic bag hot-melt equipment for rapid cooling and solidification. However, this precise control will increase the cost of the equipment, and the heat sealing knife is quickly heated and cooled for a long time, and the temperature difference is too large, which can easily shorten the life of the heat sealing knife. Summary of the invention

[0005] The present application proposes a plastic bag production equipment based on a multi-point centralized hot-melt process, which is equipped with a roller-shaped heat-sealing knife for rolling and heat-sealing plastic bags. The roller-shaped heat-sealing knife squeezes out the air between the plastic belts when rolling, and only the part of the roller-shaped heat-sealing knife that is about to contact the plastic bag is in a high-temperature state. The rotation of the heat-sealing knife cooperates with the elastic force of spring I to make the high-temperature resistant magnet block I reciprocate, and the reciprocating high-temperature resistant magnet block I constantly changes the suction force on the high-temperature resistant magnet block II to make the high-temperature resistant magnet block II move up and down. The high-temperature resistant magnet block II that moves up and down forces the elastic rubber layer to deform to form an airflow to cool the heat-sealed part, so as to solve the problems that the gas between the plastics cannot be discharged during heat sealing with the existing heat-sealing knife to form bubbles, and the heat-sealing knife has a poor cooling and curing effect on the hot air part and a high cost.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: a plastic bag production equipment based on a multi-point centralized hot-melt process, comprising a fixed seat, symmetrical clamps are arranged on both sides of the bottom end of the fixed seat, a heat sealing knife is arranged below the fixed seat, and the two ends of the heat sealing knife are respectively movably sleeved in the clamps at the two ends; a storage cavity is opened in the heat sealing knife, an electric heating plate is placed in the storage cavity, an electric heating seat is arranged at one end of the electric heating plate, and the electric heating seat is sleeved in one of the clamps; a transmission roller is arranged at the center of one end of the heat sealing knife away from the electric heating seat, and an intelligent control motor is arranged on the side of the top end of the fixed seat away from the electric heating seat, and the output end of the intelligent control motor is connected to the transmission roller for controlling the heat sealing knife to rotate.

[0007] Preferably, the cross-section of the electric heating plate is arc-shaped, the angle of the arc-shaped electric heating plate is between ninety degrees and one hundred and ten degrees, the top end of the arc-shaped electric heating plate is close to the middle of the heat sealing knife, and the bottom end of the arc-shaped electric heating plate is close to the bottom of the heat sealing knife, which is used to heat the part of the heat sealing knife that is about to contact the plastic bag.

[0008] Preferably, an arc-shaped limit plate is provided at the bottom end of the electric heating plate, a high-temperature resistant magnet block I is provided between the outer wall of the limit plate and the inner wall of the storage cavity, and a spring I is provided between the high-temperature resistant magnet block I and the electric heating plate to limit the movement direction of the high-temperature resistant magnet block I.

[0009] Preferably, evenly distributed rough areas are arranged on the inner wall of the storage cavity, and a smooth area is formed at a position of the inner wall of the storage cavity between adjacent rough areas.

[0010] Preferably, one side of the high temperature resistant magnet block I facing the inner wall of the storage cavity is in contact with the inner wall of the storage cavity, and one side of the high temperature resistant magnet block I facing the inner wall of the storage cavity is rough, so as to provide a force for movement to the high temperature resistant magnet block I.

[0011] Preferably, a bellows is provided on the outside of one side of the heat sealing knife away from the electric heating plate, a vertical fixing plate connected to a fixing seat is provided on the top of the bellows, and an air outlet is provided at the bottom of the bellows for discharging or inhaling cooling airflow.

[0012] Preferably, an opening is provided on the outer side of the top of the bellows, an elastic rubber layer is provided at the opening, a high temperature resistant magnet block II is provided at the end of the elastic rubber layer away from the heat sealing knife, a spring II is provided between the top of the high temperature resistant magnet block II and the fixed plate, and the high temperature resistant magnet block II and the opposite end of the high temperature resistant magnet block I are attracted to each other to drive the elastic rubber layer to deform.

[0013] Preferably, there is a gap between the outer wall of the electric heating plate and the inner wall of the storage cavity, and the distance of the gap is no more than two millimeters, so as to reduce direct contact wear and deformation of the heat sealing knife.

[0014] The present application provides a plastic bag production equipment based on a multi-point centralized hot-melt process. A drum-shaped heat-sealing knife is arranged so that when the cylinder drives the heat-sealing knife to move downward, only a small area at the bottom of the drum-shaped heat-sealing knife contacts the plastic bag. At this time, another cylinder drives the heat-sealing knife to move horizontally and linearly, and an intelligent control motor drives the heat-sealing knife to roll, so that the drum-shaped heat-sealing knife moves linearly and squeezes the plastic bag while rolling and squeezing the plastic bag, so that the air in the plastic bag is pressed away, reducing the amount of bubbles at the heat-sealed part of the plastic bag.

[0015] At the same time, by arranging an arc-shaped electric heating plate at the bottom of the drum-shaped heat-sealing knife, the electric heating plate will only heat the part of the heat-sealing knife that is about to roll and contact the plastic bag, and the part of the heat-sealing knife that rolls away from the electric heating plate will no longer be in close contact with the electric heating plate, thereby cooling down. However, due to the influence of the air heated by the electric heating plate in the storage cavity, this temperature drop will not be too large, and only the part of the heat-sealing knife far away from the electric heating plate will be in a relatively low temperature state compared with the part close to the electric heating plate, so that the heat-sealing knife will not be in a high temperature state for a long time, nor will it be in a low temperature state with a large temperature difference, thereby extending the service life of the heat-sealing knife.

[0016] At the same time, through the rolling of the heat sealing knife, the evenly distributed rough area on the inner wall of the heat sealing knife intermittently contacts the high temperature resistant magnet block I, rubs the high temperature resistant magnet block I, and pushes the high temperature resistant magnet block I to move upward, so that the high temperature resistant magnet block I and the high temperature resistant magnet block II are close to each other, and the suction force of the high temperature resistant magnet block I on the high temperature resistant magnet block II is enhanced, so that the high temperature resistant magnet block II presses the elastic rubber layer downward, and pushes the gas in the bellows to be ejected from the air outlet at the bottom, and the area exposed by the rolling of the heat sealing knife is jet-cooled. In the process of the movement of the high temperature resistant magnet block I, the spring I is pulled to store energy, so that the pulling force continues to increase, pulling the high temperature resistant magnet block I to resist The friction provided by the rough area is constantly increasing. Due to the continuous rotation of the heat sealing knife, the rough area will gradually separate from the high temperature resistant magnet block I. At this time, the spring I will pull the high temperature resistant magnet block I to reset, so that the high temperature resistant magnet block I and the high temperature resistant magnet block II are separated. The suction force of the high temperature resistant magnet block I on the high temperature resistant magnet block II is weakened, so that the energy-storing spring II pulls the high temperature resistant magnet block II upward to pull the rubber layer, increase the space in the bellows, and absorb the outside air through the air vent at the bottom of the bellows. A flowing airflow is formed in the area exposed by the heat sealing knife, and this area is cooled, thereby accelerating the cooling and solidification speed of the part of the plastic bag that is heat-sealed by the heat sealing knife. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute a part of the specification, illustrate embodiments disclosed in the present application and, together with the description, serve to explain the principles disclosed in the present application.

[0018] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0020] Figure 2 It is a schematic diagram of the structure of the fixing seat of the present invention;

[0021] Figure 3 It is a schematic diagram of the heat sealing knife and bellows structure position of the present invention;

[0022] Figure 4 This is a schematic diagram of the internal structure of the heat sealing knife of the present invention;

[0023] Figure 5 It is a schematic diagram of the structural distribution of the present invention.

[0024] Among them: 1. Fixed seat; 2. Clamp; 3. Intelligent control motor; 4. Heat sealing knife; 41. Storage cavity; 42. Smooth area; 43. Rough area; 5. Transmission roller; 6. Electric heating seat; 7. Electric heating plate; 8. Limiting plate; 9. High temperature resistant magnet block I; 10. Spring I; 11. Bellows; 12. Fixed plate; 13. Elastic rubber layer; 14. High temperature resistant magnet block II; 15. Spring II. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] Embodiment 1

[0027] See also Figure 1 , including a fixed seat 1, a cylinder I is fixedly arranged above the fixed seat 1 to drive the fixed seat 1 to move up and down, and the fixed seat 1 and the heat-sealing knife 4 are driven to move up and down by the cylinder I, so that the heat-sealing knife 4 is pressed downward on the plastic bag to perform heat sealing, and moves upward to leave the plastic bag after the heat sealing is completed, and a cylinder II is fixedly arranged on one side of the fixed seat 1 to drive the fixed seat 1 to perform horizontal linear movement, and the fixed seat 1 and the heat-sealing knife 4 are driven to perform horizontal linear movement by the cylinder II. When the heat-sealing knife 4 is pressed on the plastic bag, the heat-sealing knife 4 is driven to perform linear extrusion on the plastic bag, so that the heat-sealing knife 4 can perform heat sealing on the plastic bag over a large area, and can also push the gas in the plastic bag to move in the direction of the heat-sealing knife 4, so that the air It is discharged in advance from the heat-sealed area. When the heat sealing is completed, when cylinder I drives the heat-sealing knife to lift up, cylinder II will also drive the heat-sealing knife 4 to reset in a straight line. When facing the needs of heat-sealing surfaces of different sizes, the horizontal displacement distance of the heat-sealing knife 4 can be adjusted by cylinder II, thereby ensuring the needs of heat-sealing surfaces of different areas. When facing plastic bags of different thicknesses, the horizontal displacement speed of the heat-sealing knife 4 can be adjusted by cylinder II, thereby ensuring that sufficient heat-sealing time is provided for plastic bags of different thicknesses. Cylinders I and II are fixedly connected to the frame of the existing multi-point centralized hot-melt equipment, so that the fixing seat 1 can be fixed in position by cylinders I and II, and the heat-sealing knife 4 can be fixed in position by the fixing seat 1.

[0028] See also Figures 1 to 4Symmetrical clamps 2 are fixed by bolts on both sides of the top of the fixed seat 1, and a roller-shaped heat-sealing knife 4 is arranged under the fixed seat 1. The two ends of the heat-sealing knife 4 are movably sleeved in the clamps 2 at both ends, so that the heat-sealing knife 4 can follow the fixed seat 1 to move up and down and horizontally under the restriction of the clamp 2, and does not delay the rotation of the heat-sealing knife 4 in the clamp 2. A storage cavity 41 is opened in the heat-sealing knife 4, and one end of the storage cavity 41 is open. An electric heating seat 6 is fixedly sleeved in the clamp 2 near the opening of the storage cavity 41. One end of the storage cavity 41 in the electric heating seat 6 is fitted with the open end of the storage cavity 41, and the opening of the storage cavity 41 is closed by the electric heating seat 6 to avoid a large amount of heat loss in the storage cavity 41. An arc-shaped bottom of one end of the storage cavity 41 in the electric heating seat 6 is fixedly connected The electric heating plate 7, the angle of the arc-shaped electric heating plate 7 is between ninety degrees and one hundred and ten degrees, the top end of the arc-shaped electric heating plate 7 is close to the middle of the heat sealing knife 4, and the bottom end of the arc-shaped electric heating plate 7 is close to the bottom of the heat sealing knife 4, so that the electric heating plate 7 will only heat the part of the heat sealing knife 4 that is about to roll and contact the plastic bag, and the part of the heat sealing knife 4 that rolls away from the electric heating plate 7 will no longer be in close contact with the electric heating plate 7, thereby cooling down, but affected by the air heated by the electric heating plate 7 inside the storage cavity 41, this temperature drop will not be too large, and will only make the part of the heat sealing knife 4 away from the electric heating plate 7 compared with the part close to the electric heating plate 7 in a relatively low temperature state, so that the heat sealing knife 4 will not be in a high temperature state for a long time, nor will it be in a low temperature state with a large temperature difference, thereby extending the service life of the heat sealing knife 4.

[0029] See also Figure 1 to Figure 2 , Figure 4 A transmission roller 5 is welded at the center of one end of the heat sealing knife 4 away from the electric heating seat 6, and an intelligent control motor 3 is bolted to the side of the top of the fixed seat 1 away from the electric heating seat 6. The output end of the intelligent control motor 3 is transmission-connected with the transmission roller 5, and the transmission connection method can be a gear meshing connection, a chain transmission connection or a belt transmission connection, etc. The power is provided by the intelligent control motor 3, and the power is transmitted to the transmission roller 5 through the transmission device of the transmission connection, so that the transmission roller 5 drives the heat sealing knife 4 to rotate, constantly changing the heated part of the heat sealing knife 4 and the electric heating plate 7, and constantly changing the heat-sealing position of the heat sealing knife 4 and the plastic bag. By changing the rotation speed of the heat sealing knife 4 by the intelligent control motor 3, the time for the heat sealing knife 4 to pass the electric heating plate 7 can be changed, and the temperature of the heat sealing knife 4 passing the electric heating plate 7 can be changed, which is used to cope with heat sealing requirements of different temperatures.

[0030] Embodiment 2

[0031] See also Figure 5 On the basis of the first embodiment, evenly distributed rough areas 43 are provided on the inner wall of the placement cavity 41 , and a smooth area 42 is formed at a portion of the inner wall of the placement cavity 41 between adjacent rough areas 43 .

[0032] See also Figures 4 to 5 The bottom end of the electric heating plate 7 is fixedly connected with an arc-shaped limiting plate 8, and a high-temperature resistant magnet block Ⅰ9 is movably sleeved between the outer wall of the limiting plate 8 and the inner wall of the storage cavity 41. The side of the high-temperature resistant magnet block Ⅰ9 facing the inner wall of the storage cavity 41 is in contact with the inner wall of the storage cavity 41, and this side of the high-temperature resistant magnet block Ⅰ9 is rough, so that the limiting plate 8 can cooperate with the inner wall of the storage cavity 41 to limit the movement direction of the high-temperature resistant magnet block Ⅰ9, so that the high-temperature resistant magnet block Ⅰ9 can only keep in contact with the inner wall of the storage cavity 41 and rotate with the center of the heat sealing knife 4 as the center. The end of the high-temperature resistant magnet block Ⅰ9 facing the electric heating plate 7 is fixedly connected with a spring Ⅰ10, and the spring Ⅰ10 is away from the high-temperature resistant One end of the magnet block Ⅰ9 is fixedly connected to the bottom end of the electric heating plate 7. The rolling of the heat sealing knife 4 causes the evenly distributed rough area 43 on the inner wall of the heat sealing knife 4 to intermittently contact the high temperature resistant magnet block Ⅰ9, rub the high temperature resistant magnet block Ⅰ9, and push the high temperature resistant magnet block Ⅰ9 to move upward, pulling the spring Ⅰ10, so that the spring Ⅰ10 stretches and stores energy, and the pulling force continues to increase, pulling the high temperature resistant magnet block Ⅰ9 to resist the increasing friction force provided by the rough area 43. Due to the continuous rotation of the heat sealing knife 4 and the pulling force of the spring Ⅰ10, the rough area 43 will gradually separate from the high temperature resistant magnet block Ⅰ9, so that the high temperature resistant magnet block Ⅰ9 contacts the smooth area 42. At this time, the spring Ⅰ10 will pull the high temperature resistant magnet block Ⅰ9 to reset.

[0033] See also Figure 1 , Figure 3 , Figure 5An arc-shaped bellows 11 is arranged on the outside of one side of the heat sealing knife 4 away from the electric heating plate 7, a vertical fixing plate 12 is fixedly connected to the top of the bellows 11, and the fixing plate 12 is fixedly connected to the fixing seat 1 by bolts, an air outlet is opened at the bottom of the bellows 11, an opening is opened on the outside of the top of the bellows 11, and an elastic rubber layer 13 is fixedly connected to the opening, and a high-temperature resistant magnet block II 14 is fixedly connected to the end of the elastic rubber layer 13 away from the heat sealing knife 4, a spring II 15 is fixedly connected to the top of the high-temperature resistant magnet block II 14, and the top of the spring II 15 is fixedly connected to the fixing plate 12, and the high-temperature resistant magnet block II 14 and the opposite ends of the high-temperature resistant magnet block I 9 are attracted to each other, and when the high-temperature resistant magnet block I 9 moves upward, the high-temperature resistant magnet block I 9 and the high-temperature resistant magnet block II 14 are close to each other, and the suction force of the high-temperature resistant magnet block I 9 on the high-temperature resistant magnet block II 14 is enhanced , so that the high temperature resistant magnet block Ⅱ14 presses the elastic rubber layer 13 downward, pushes the gas in the bellows 11 to be ejected from the tuyere at the bottom, and performs jet cooling on the area exposed by the heat sealing knife 4. At this time, the high temperature resistant magnet block Ⅱ14 pressed downward will pull the spring Ⅱ15 to deform, stretch and store energy. When the high temperature resistant magnet block Ⅰ9 is reset downward, the high temperature resistant magnet block Ⅰ9 is separated from the high temperature resistant magnet block Ⅱ14, and the suction force of the high temperature resistant magnet block Ⅰ9 on the high temperature resistant magnet block Ⅱ14 is weakened, so that the energy-storing spring Ⅱ15 pulls the high temperature resistant magnet block Ⅱ14 to pull the elastic rubber layer 13 upward, thereby increasing the space in the bellows 11, and absorbing the outside air through the tuyere at the bottom end of the bellows 11, forming a flowing airflow in the area exposed by the heat sealing knife 4, and cooling this area, thereby accelerating the cooling and solidification speed of the part of the plastic bag heat-sealed by the heat sealing knife 4.

[0034] Embodiment 3

[0035] See also Figure 5 On the basis of the second embodiment, there is a gap between the outer wall of the electric heating plate 7 and the inner wall of the storage cavity 41, and the distance of the gap is not greater than two millimeters, so that the electric heating plate 7 does not directly contact the inner wall of the storage cavity 41, but heats the air in the gap, and then heats the heat sealing knife 4 through this part of air, thereby avoiding the deformation and wear of the electric heating plate 7 and the heat sealing knife 4 caused by the long-term friction of the electric heating plate 7 with the inner wall of the storage cavity 41. Since the arc angle of the electric heating plate 7 is large, there will be enough time for the heat sealing knife 4 to heat to hot melting before contacting the plastic bag.

Claims

1. A plastic bag production equipment based on multi-point centralized hot melt process, characterized in that: It comprises a fixed seat (1), symmetrical clamps (2) are arranged on both sides of the bottom end of the fixed seat (1), a roller-shaped heat sealing knife (4) is arranged below the fixed seat (1), and the two ends of the heat sealing knife (4) are movably sleeved in the clamps (2) at the two ends respectively; The heat sealing knife (4) is provided with a storage cavity (41), an electric heating plate (7) is placed in the storage cavity (41), an electric heating seat (6) is provided at one end of the electric heating plate (7), and the electric heating seat (6) is sleeved in one of the clamps (2); A transmission roller (5) is arranged at the center of one end of the heat sealing knife (4) away from the electric heating seat (6), and an intelligent control motor (3) is arranged at the top end of the fixed seat (1) away from the electric heating seat (6). The output end of the intelligent control motor (3) is connected to the transmission roller (5) in a transmission manner and is used to control the heat sealing knife (4) to rotate.

2. The plastic bag production equipment based on multi-point centralized hot melt process according to claim 2 is characterized in that: The cross section of the electric heating plate (7) is arc-shaped, and the angle of the arc-shaped electric heating plate (7) is between ninety degrees and one hundred and ten degrees. The top end of the arc-shaped electric heating plate (7) is close to the middle of the heat sealing knife (4), and the bottom end of the arc-shaped electric heating plate (7) is close to the bottom of the heat sealing knife (4), so as to heat the part of the heat sealing knife (4) that is about to contact the plastic bag.

3. The plastic bag production equipment based on multi-point centralized hot melt process according to claim 1 is characterized in that: An arc-shaped limiting plate (8) is arranged at the bottom end of the electric heating plate (7), a high temperature resistant magnet block I (9) is arranged between the outer wall of the limiting plate (8) and the inner wall of the storage cavity (41), and a spring I (10) is arranged between the high temperature resistant magnet block I (9) and the electric heating plate (7) for limiting the movement direction of the high temperature resistant magnet block I (9).

4. The plastic bag production equipment based on multi-point centralized hot melt process according to claim 3 is characterized in that: The inner wall of the storage cavity (41) is provided with uniformly distributed rough areas (43), and the inner wall of the storage cavity (41) between adjacent rough areas (43) forms a smooth area (42).

5. The plastic bag production equipment based on multi-point centralized hot-melt process according to claim 4 is characterized in that: The side of the high temperature resistant magnet block I (9) facing the inner wall of the storage cavity (41) is in contact with the inner wall of the storage cavity (41), and the side of the high temperature resistant magnet block I (9) facing the inner wall of the storage cavity (41) is rough, so as to provide a force for movement to the high temperature resistant magnet block I (9).

6. The plastic bag production equipment based on multi-point centralized hot-melt process according to claim 3 is characterized in that: A bellows (11) is arranged on the outside of the heat sealing knife (4) on a side away from the electric heating plate (7); a vertical fixing plate (12) connected to the fixing seat (1) is arranged on the top of the bellows (11); and an air outlet is arranged on the bottom of the bellows (11) for discharging or inhaling cooling airflow.

7. The plastic bag production equipment based on multi-point centralized hot-melt process according to claim 6 is characterized in that: An opening is provided on the outer side of the top of the bellows (11), and an elastic rubber layer (13) is provided at the opening. A high temperature resistant magnet block II (14) is provided at one end of the elastic rubber layer (13) away from the heat sealing knife (4). A spring II (15) is provided between the top of the high temperature resistant magnet block II (14) and the fixed plate (12). The high temperature resistant magnet block II (14) and the opposite end of the high temperature resistant magnet block I (9) attract each other, so as to drive the elastic rubber layer (13) to deform.

8. The plastic bag production equipment based on multi-point centralized hot-melt process according to claim 1 is characterized in that: There is a gap between the outer wall of the electric heating plate (7) and the inner wall of the storage cavity (41), and the distance of the gap is no more than two millimeters, so as to reduce direct contact wear and deformation of the heat sealing knife (4).

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