A device for uniformly and rapidly cooling a large plastic blown film die

Abstract

The present invention discloses a device for uniformly and rapidly cooling a large plastic blown film die, which includes an internal cooling mechanism, an external cooling mechanism, and a bottom cooling mechanism. The internal cooling mechanism is arranged inside the die cavity and is disposed opposite to the die flow splitter cone. The internal cooling mechanism drains the heat inside the die through the through holes at the bottom of the die to the bottom surface of the die, and the heat is dissipated to the outside of the die through the through holes on the bottom surface of the die. A bottom cooling mechanism is arranged on the bottom surface of the die, and the bottom cooling mechanism disperses the heat on the bottom surface of the die. An external cooling mechanism is arranged on the outer wall of the die, and the external cooling mechanism disperses the heat on the outer wall of the die. The present invention aims to effectively shorten the die cooling time, protect the blown film die, extend the service life of the blown film die, reduce production costs, and improve the quality of the film product.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic blown film, and in particular to a device for uniformly and rapidly cooling a large plastic blown film die. Background Art

[0002] With the development of China's facility agriculture and horticulture, the required greenhouse films are getting wider and wider. To meet the development of greenhouse films, a large number of blown film dies with a width of more than 2000 mm have been developed and produced in China. Now the largest die reaches 3600 mm, and its structure is shown in Figure 1 . When the large die is in use, heaters are installed on the outer surface and the inner surface to heat the die to above 200 °C, so that the polyethylene raw materials and masterbatches have fluidity in the die. When the production task is completed and the machine stops, cooling from a temperature above 200 °C to room temperature originally relied on natural cooling, which took 5 - 10 days. The die is easily caused by plastic raw materials, especially various masterbatches, to decompose at high temperature for a long time, forming a carbonization phenomenon on the surface of the die runner. The carbonized layer adheres to the surface of the die runner, seriously affecting the quality of the film product and the service life of the die, increasing the cleaning frequency of the die. Seriously, it needs to be manually cleaned once every 2 - 3 months, and cleaning the die requires a large amount of manpower and material resources. Summary of the Invention

[0003] The present invention provides a device for uniformly and rapidly cooling a large plastic blown film die to solve the technical problems that the natural cooling time of the blown film die is long and the cleaning requires a large amount of manpower and material resources.

[0004] The present invention is achieved by the following measures:

[0005] A device for uniformly and rapidly cooling a large plastic blown film die includes an inner cooling mechanism, an outer cooling mechanism, and a lower cooling mechanism. The inner cooling mechanism is arranged in the inner cavity of the die and is disposed opposite to the die's flow dividing cone. The inner cooling mechanism diverts the heat inside the die to the bottom surface of the die, and the heat is dissipated to the outside of the die through the through holes on the bottom surface of the die. The lower cooling mechanism is arranged on the bottom surface of the die, and the lower cooling mechanism disperses the heat on the bottom surface of the die. The outer cooling mechanism is arranged on the side wall of the die, and the outer cooling mechanism disperses the heat on the outer wall of the die.

[0006] Further, the internal cooling mechanism includes a chamber, the chamber includes an external chamber and an internal chamber, the cross-section of the external chamber is V-shaped, the cross-section of the internal chamber is triangular, and the cross-section formed after the internal chamber is fitted with the external chamber is rectangular. Air outlet A is provided on the side wall and the bottom surface of the external chamber, and air outlet A is also provided on the internal chamber. A ventilation hole is provided at the fitting position of the internal chamber and the external chamber. A rigid air duct is provided on the upper end surface of the chamber, a flexible air duct is fixedly provided on the rigid air duct, the upper end of the flexible air duct is arranged above the rigid air duct, and the lower end of the flexible air duct is connected to the air outlet B of the blower air bag.

[0007] Further, the descending temperature mechanism includes an annular cooling air ring A, the annular cooling air ring A includes an outer ring A and a baffle A, the baffle A is annularly arranged in the outer ring A with the axis of the outer ring A as the center, the baffle A includes an upper baffle A and a lower baffle A, the upper baffle A is fixedly connected to the upper side surface inside the outer ring A, the lower baffle A is fixedly connected to the lower side surface inside the outer ring A, circular small holes are provided on the side wall of the outer ring A, rigid air ducts B are uniformly arranged on the side wall of the outer ring A, flexible air ducts B are arranged in the rigid air ducts B, the upper end of the flexible air duct B is flush with the upper end surface of the rigid air duct B, the lower end of the flexible air duct B is connected to the air outlet B of the blower air bag, a baffle plate A is provided at the upper end of the outer ring A, and the baffle plate A is arranged at the upper part of the outer ring A.

[0008] Further, the external cooling mechanism includes an annular cooling air ring B, the annular cooling air ring B includes an outer ring B and a baffle B, the baffle B is annularly arranged in the outer ring B with the axis of the outer ring B as the center, the baffle B includes an upper baffle B and a lower baffle B, the upper baffle B is fixedly connected to the upper side surface inside the outer ring B, the lower baffle B is fixedly connected to the lower side surface inside the outer ring B, circular small holes are provided on the side wall of the outer ring B, rigid air ducts C are uniformly arranged on the side wall of the outer ring B, flexible air ducts C are arranged in the rigid air ducts C, the upper end of the flexible air duct C is flush with the upper end surface of the rigid air duct C, the lower end of the flexible air duct C is connected to the air outlet B of the blower air bag, a baffle plate B is provided at the upper end of the outer ring B, and the baffle plate B is arranged at the upper and lower parts of the annular wall of the outer ring B.

[0009] Further, the air inlet direction of the rigid air duct B is parallel to the tangent direction of the annular cooling air ring A, and the air inlet direction of the rigid air duct C is parallel to the tangent direction of the annular cooling air ring B.

[0010] Further, a left baffle and a right baffle are arranged in the external chamber, the left baffle is fixedly connected to the lower end surface of the external chamber, and the right baffle is arranged at the fitting position of the external chamber and the internal chamber.

[0011] Advantages of the present invention:

[0012] 1. The present invention aims to effectively shorten the cooling time of the mold, protect the blown film mold, extend the service life of the blown film mold, reduce production costs, and improve the quality of film products.

[0013] 2. The internal cooling device cools the inside of the mold. The internal cooling mechanism diverts the heat inside the mold to the bottom surface of the mold, and the heat is dissipated to the outside of the mold through the through holes on the bottom surface of the mold. A downward cooling mechanism is arranged on the bottom surface of the mold, and the downward cooling mechanism disperses the heat on the bottom surface of the mold. The downward cooling mechanism disperses and takes away the heat on the bottom surface of the mold. An external cooling mechanism is arranged on the outer wall of the mold, and the external cooling mechanism disperses the heat on the outer wall of the mold.

[0014] 3. The chamber of the internal cooling mechanism is divided into an external chamber and an internal chamber, and the external chamber and the internal chamber form a dam-type air chamber structure, which can evenly distribute the cold air. The outlet B of the air blower air bag is used to introduce the external cooling air into the chamber of the internal cooling mechanism through a flexible air duct. The cold air first enters the external chamber, and the cold air hits the inclined surface of the external chamber. After secondary distribution, it evenly enters the internal chamber, and the air is evenly blown into the inner cavity of the mold through the air outlet of the internal chamber. Since the air blower provides cold air, the cold air pressure is high, and the cold air drives the heat to flow towards the bottom of the mold. The heat flowing to the bottom of the mold is dissipated to the outside of the mold through the through holes at the bottom of the mold. When the mold is working normally, the hard air duct is blocked by the gland, which does not affect the film blowing function of the mold.

[0015] 4. The outer ring A of the downward cooling mechanism is arranged at the bottom surface of the mold. The outlet B of the air blower air bag is used to introduce the external cold air into the outer ring A of the downward cooling mechanism through the hose B. Since there are circular holes on the outer ring A, the cold air enters the inside of the outer ring A through the circular holes. Since there is an upper baffle A and a lower baffle A inside the outer ring A, and the distance between the upper baffle A and the axis is less than the distance between the lower baffle A and the axis, the cold air first hits the lower baffle A. After secondary distribution by the lower baffle A, the cold air hits the upper baffle A again, which can adjust the direction of the cold air, there is no dead angle of cold air, and the cold air is evenly distributed to the bottom of the mold. Baffle plates A are arranged on the inner and outer ring walls of the outer ring A, and the baffle plates A can change the direction of the air, so that the cooling air can fully blow to the bottom surface of the mold, making the air more fully utilized, and achieving the purpose of taking away the heat at the bottom of the mold.

[0016] 5. Wrap the outer ring B of the external cooling mechanism around the outer wall of the mold. Use the air outlet B of the blower air bag to introduce external cold air into the outer ring B of the external cooling mechanism through the hose C. Since there are circular small holes on the outer ring B, the cold air enters the inside of the outer ring B through the circular small holes. Since there are an upper baffle B and a lower baffle B inside the outer ring B, and the distance between the upper baffle B and the axis is less than the distance between the lower baffle B and the axis, the cold air first hits the lower baffle B and is redistributed by the lower baffle B.

[0017] 6. The inlet direction of the rigid air duct B is parallel to the tangent direction of the annular cooling air ring A, and the inlet direction of the rigid air duct C is parallel to the tangent direction of the annular cooling air ring B, so that the air outlet is more uniform, and the cooling effect is improved by making full use of the air volume.

[0018] 7. The internal cooling device and the lower cooling device can be installed when installing the equipment, and the external cooling device is installed after the debugging is completed. Such a structure not only does not affect the normal operation of the original equipment, slows down the speed of the carbonization phenomenon on the surface of the mold runner, reduces the number of mold cleaning times, improves the service life of the mold, and improves the quality of the film products. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the mold.

[0020] Figure 2 It is a schematic structural diagram of the cooperation between the internal cooling mechanism, the external cooling mechanism, the lower cooling mechanism and the mold.

[0021] Figure 3 It is a schematic structural diagram of the internal cooling mechanism.

[0022] Figure 4 It is a schematic structural diagram of the cooperation between the external cooling mechanism and the mold.

[0023] Figure 5 It is a schematic structural diagram of the external cooling mechanism.

[0024] Figure 6 It is a sectional view of the external cooling mechanism.

[0025] Figure 7 It is a schematic structural diagram of the cooperation between the lower cooling mechanism and the mold.

[0026] Figure 8 It is a schematic structural diagram of the lower cooling mechanism.

[0027] Figure 9 It is a sectional view of the lower cooling mechanism.

[0028] Among them, the reference numerals are: 1. Inner cooling mechanism; 11. Chamber; 111. External chamber; 112. Internal chamber; 12. Air outlet A; 13. Rigid air duct; 14. Flexible air duct; 2. Outer cooling mechanism; 21. Annular cooling air ring B; 211. Outer ring B; 212. Baffle B; 2121. Upper baffle B; 2122. Lower baffle B; 22. Rigid air duct C; 23. Flexible air duct C; 24. Baffle plate B; 3. Lower cooling mechanism; 31. Annular cooling air ring A; 311. Outer ring A; 312. Baffle A; 3121. Upper baffle A; 3122. Lower baffle A; 32. Rigid air duct B; 33. Flexible air duct B; 34. Baffle plate A; 4. Mold inner cavity; 5. Mold flow splitting cone; 6. Mold. Detailed implementation manners

[0029] To clearly illustrate the technical features of this solution, the following elaborates on this solution through specific implementation manners.

[0030] See Figure 1 and Figure 2 Based on the purpose of effectively shortening the mold cooling time, protecting the blown film mold, extending the service life of the blown film mold, reducing production costs, and improving the quality of film products, the present invention provides a device for uniformly and rapidly cooling a large plastic blown film mold, including an inner cooling mechanism 1, an outer cooling mechanism 2, and a lower cooling mechanism 3. The inner cooling mechanism 1 is arranged inside the mold inner cavity 4 and is disposed opposite to the mold flow splitting cone 5. The inner cooling device cools the inside of the mold. The inner cooling mechanism 1 diverts the heat inside the mold to the bottom surface of the mold 6, and the heat is dissipated to the outside of the mold through the through holes on the bottom surface of the mold. The lower cooling mechanism 3 is arranged on the bottom surface of the mold 6, and the lower cooling mechanism 3 disperses the heat on the bottom surface of the mold. The lower cooling mechanism 3 disperses and takes away the heat on the bottom surface of the mold. The outer cooling mechanism 2 is arranged on the outer wall of the mold 6, and the outer cooling mechanism 2 disperses the heat on the outer wall of the mold.

[0031] See Figure 3 The inner cooling mechanism 1 includes a chamber 11. The chamber includes an external chamber and an internal chamber. The cross-section of the external chamber is V-shaped, and the cross-section of the internal chamber is triangular. The cross-section formed after the internal chamber is fitted with the external chamber is rectangular. Air outlets A 12 are provided on the side wall and the bottom surface of the external chamber. Air outlets A are also provided on the internal chamber. Ventilation holes are provided at the fitting position of the internal chamber and the external chamber. A rigid air duct 13 is provided on the upper end surface of the chamber 11. A flexible air duct 14 is fixedly provided on the rigid air duct 13. The upper end of the flexible air duct 14 is arranged above the rigid air duct 13, and the lower end of the flexible air duct 14 is connected to the air outlet B 8 of the fan air bag 7.

[0032] The chamber of the inner cooling mechanism is divided into an external chamber 111 and an internal chamber 112. The external chamber and the internal chamber form a dike-type air chamber structure, which can evenly distribute the cold air.

[0033] Working principle of the internal cooling mechanism of the present invention: The outlet B of the blower air receiver is used to introduce external cooling air into the chamber of the internal cooling mechanism through a flexible air duct. The cold air first enters the external chamber, strikes the inclined surface of the external chamber, and after secondary distribution, evenly enters the internal chamber. The air is evenly blown into the inner cavity of the mold through the outlet of the internal chamber. Since the blower provides cold air, the cold air has a high pressure, and the cold air drives the heat to flow towards the bottom of the mold. The heat flowing to the bottom of the mold is dissipated to the outside of the mold through the through holes at the bottom of the mold. When the mold is working normally, the hard air duct is blocked by the gland, which does not affect the film blowing function of the mold.

[0034] See Figures 7 - 9 , the lower cooling mechanism 3 includes an annular cooling air ring A31. The annular cooling air ring A31 includes an outer ring A311 and a baffle A312. The baffle A312 is annularly arranged in the outer ring A with the axis of the outer ring A311 as the center. The baffle A312 includes an upper baffle A3121 and a lower baffle A3122. The upper baffle A is fixedly connected to the upper side surface inside the outer ring A, and the lower baffle A is fixedly connected to the lower side surface inside the outer ring A. Circular small holes are provided on the side wall of the outer ring A, and hard air ducts B32 are evenly arranged on the side wall of the outer ring A311. A flexible air duct B33 is arranged inside the hard air duct B32. The upper end of the flexible air duct B33 is flush with the upper end surface of the hard air duct B32, and the lower end of the flexible air duct B33 is connected to the outlet B8 of the blower air receiver 7. A baffle plate A34 is arranged at the upper end of the outer ring A311, and the baffle plate A34 is arranged at the upper part of the outer ring A311.

[0035] Working principle of the lower cooling mechanism: The outer ring A of the lower cooling mechanism is arranged at the bottom surface of the mold. The outlet B of the blower air receiver is used to introduce external cold air into the outer ring A of the lower cooling mechanism through the hose B. Since there are circular small holes on the outer ring A, the cold air enters the inside of the outer ring A through the circular small holes. Since there are an upper baffle A and a lower baffle A inside the outer ring A, and the distance between the upper baffle A and the axis is less than the distance between the lower baffle A and the axis, the cold air first strikes the lower baffle A. After secondary distribution by the lower baffle A, the cold air then strikes the upper baffle A, which can adjust the direction of the cold air and there is no dead angle of cold air. The cold air is evenly distributed to the bottom of the mold. Baffle plates A are arranged on the inner and outer ring walls of the outer ring A. The baffle plates A can change the direction of the air, enabling the cooling air to fully blow to the bottom surface of the mold, making the air more fully utilized, and achieving the purpose of taking away the heat at the bottom of the mold.

[0036] See Figures 4 - 6, the external cooling mechanism 2 includes an annular cooling air ring B21. The annular cooling air ring B21 includes an outer ring B211 and a baffle B212. The baffle B212 is annularly arranged inside the outer ring B with the axis of the outer ring B211 as the center. The baffle B212 includes an upper baffle B2121 and a lower baffle B2122. The upper baffle B is fixedly connected to the upper inner side surface of the outer ring B, and the lower baffle B is fixedly connected to the lower inner side surface of the outer ring B. Circular small holes are provided on the side wall of the outer ring B, and rigid air ducts C22 are evenly arranged on the side wall of the outer ring B. A flexible air duct C23 is arranged inside the rigid air duct C22. The upper end of the flexible air duct C23 is flush with the upper end surface of the rigid air duct C22, and the lower end of the flexible air duct C23 is connected to the air outlet B8 of the fan air bag 7. A deflector B24 is provided at the upper end of the outer ring B, and the deflector B24 is arranged at the upper and lower parts of the annular wall of the outer ring B.

[0037] Working principle of the external cooling mechanism: Wrap the outer ring B of the external cooling mechanism around the outer wall of the mold. Use the air outlet B of the fan air bag to introduce external cold air into the outer ring B of the external cooling mechanism through the hose C. Since there are circular small holes on the outer ring B, the cold air enters the inside of the outer ring B through the circular small holes. Since there are an upper baffle B and a lower baffle B inside the outer ring B, and the distance between the upper baffle B and the axis is less than the distance between the lower baffle B and the axis, the cold air first hits the lower baffle B. After the secondary distribution of the lower baffle B, the cold air is then hit on the upper baffle B, which can adjust the direction of the cold air, there is no dead angle of cold air, and the cold air is evenly distributed to the bottom of the mold. Deflector plates B are provided on the inner and outer annular walls of the outer ring B. The deflector plates B can change the direction of the wind, so that the cooling air can fully blow to the outer wall of the mold, making the air more fully utilized, and achieving the purpose of taking away the heat of the outer wall of the mold.

[0038] The air inlet direction of the rigid air duct B32 is parallel to the tangent direction of the annular cooling air ring A31, and the air inlet direction of the rigid air duct C22 is parallel to the tangent direction of the annular cooling air ring B21. This makes the air outlet more uniform and fully utilizes the air volume to improve the cooling effect.

[0039] A left baffle and a right baffle are provided in the external chamber. The left baffle is fixedly connected to the lower end surface of the external chamber, and a right baffle is provided at the fitting part of the external chamber and the internal chamber.

[0040] Setting the left baffle and the right baffle in the external chamber can effectively adjust the direction of the cold air and make the cold air evenly blow to the inner cavity of the mold.

[0041] The internal cooling device and the descending cooling device can be installed when installing the equipment, and the external cooling device is installed after the debugging is completed. Such a structure not only does not affect the normal operation of the original equipment, slows down the speed of the formation of carbonization on the surface of the mold runner, reduces the number of times of mold cleaning, improves the service life of the mold, and improves the quality of the film products.

[0042] The technical features not described in the present invention can be achieved by or adopted from the prior art and will not be elaborated herein. Of course, the above description is not a limitation to the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by those of ordinary skill in the art within the essence of the present invention shall also fall within the protection scope of the present invention.

Claims

1. A uniform and rapid cooling device for a large plastic blown film die, comprising an internal cooling mechanism (1), an external cooling mechanism (2) and a lower cooling mechanism (3). It is characterized in that the internal cooling mechanism (1) is arranged in the die cavity (4) and is arranged opposite to the die flow dividing cone (5). The internal cooling mechanism (1) diverts the heat inside the die to the bottom surface of the die (6), and the heat is dissipated to the outside of the die through the through holes on the bottom surface of the die. The lower cooling mechanism (3) is arranged on the bottom surface of the die (6), and the lower cooling mechanism (3) disperses the heat on the bottom surface of the die. The external cooling mechanism (2) is arranged on the outer wall of the die (6), and the external cooling mechanism (2) is used to disperse the heat on the outer wall of the die; the internal cooling mechanism (1) includes a chamber (11). The chamber includes an external chamber (111) and an internal chamber (112). The cross-section of the external chamber is V-shaped, and the cross-section of the internal chamber is triangular. The cross-section formed after the internal chamber is fitted with the external chamber is rectangular. Air outlets A (12) are arranged on the side walls and the bottom surface of the external chamber. Air outlets A are also arranged on the internal chamber. Ventilation holes are arranged at the fitting position of the internal chamber and the external chamber. A rigid air duct (13) is arranged on the upper end surface of the chamber (11). A flexible air duct (14) is fixedly arranged on the rigid air duct (13). The upper end of the flexible air duct (14) is arranged above the rigid air duct (13), and the lower end of the flexible air duct (14) is connected to the air outlet of the blower air bag; the external cooling mechanism (2) includes an annular cooling air ring B (21). The annular cooling air ring B (21) includes an outer ring B (211) and a baffle B (212). The baffle B (212) is annularly arranged in the outer ring B with the axis of the outer ring B as the center. The baffle B (212) includes an upper baffle B (2121) and a lower baffle B (2122). The upper baffle B is fixedly connected to the inner upper side surface of the outer ring B, and the lower baffle B is fixedly connected to the inner lower side surface of the outer ring B. Circular small holes are arranged on the side wall of the outer ring B. Rigid air ducts C (22) are evenly arranged on the side wall of the outer ring B. A flexible air duct C (23) is arranged in the rigid air duct C (22). The upper end of the flexible air duct C (23) is flush with the upper end surface of the rigid air duct C (22), and the lower end of the flexible air duct C (23) is connected to the air outlet B of the blower air bag. A baffle plate B (24) is arranged at the upper end of the outer ring B, and the baffle plate B (24) is arranged at the upper and lower parts of the annular wall of the outer ring B.

2. The uniform and rapid cooling device for a large plastic blown film die according to claim 1, It is characterized in that The temperature reduction mechanism (3) includes an annular cooling air ring A (31). The annular cooling air ring A (31) includes an outer ring A (311) and a baffle A (312). The baffle A (312) is annularly arranged inside the outer ring A with the axis of the outer ring A as the center. The baffle A (312) includes an upper baffle A (3121) and a lower baffle A (3122). The upper baffle A is fixedly connected to the inner upper side surface of the outer ring A, and the lower baffle A is fixedly connected to the inner lower side surface of the outer ring A. Circular small holes are provided on the side wall of the outer ring A. Hard air pipes B (32) are evenly arranged on the side wall of the outer ring A (311). A soft air pipe B (33) is arranged inside the hard air pipe B (32). The upper end of the soft air pipe B (33) is flush with the upper end surface of the hard air pipe B (32). The lower end of the soft air pipe B (33) is connected to the air outlet of the fan air bag. A baffle plate A (34) is arranged at the upper end of the outer ring A (311), and the baffle plate A (34) is arranged at the upper part of the outer ring A (311).

3. The uniform and rapid temperature reduction device for a large plastic blown film die according to claim 2, characterized in that, the air inlet direction of the hard air pipe B (32) is parallel to the tangent direction of the annular cooling air ring A (31), and the air inlet direction of the hard air pipe C (22) is parallel to the tangent direction of the annular cooling air ring B (21).

4. The uniform and rapid temperature reduction device for a large plastic blown film die according to claim 1, characterized in that, a left baffle and a right baffle are arranged in the external chamber. The left baffle is fixedly connected to the lower end surface of the external chamber, and the right baffle is arranged at the fitting position of the external chamber and the internal chamber.

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