Air knife for film slobbering equipment

Abstract

The utility model discloses an air knife for film salivation equipment. The air knife comprises an air pipe assembly and a knife mouth assembly, the air pipe assembly comprises an outer air pipe and an inner air pipe, the inner air pipe is sleeved with the outer air pipe, and the two ends of the inner air pipe are connected with air inlet pipes. The knife mouth assembly comprises a left wall plate block, a right wall plate block, an upper knife plate and a lower knife plate, the left wall plate block, the right wall plate block, the upper knife plate and the lower knife plate define a knife mouth cavity, the rear end of the knife mouth cavity is communicated with a pipe cavity of the outer air pipe through an outer small ventilation hole, and a long-strip-shaped air outlet is formed in the front lower end of the knife mouth cavity; l-shaped high-pressure air pipes are further installed on the left side and the right side of the knife mouth assembly correspondingly. Each L-shaped high-pressure air pipe comprises a high-pressure air pipe transverse section and a high-pressure air pipe vertical section, and the high-pressure air pipe transverse section is perpendicular to the high-pressure air pipe vertical section; the tail end opening of the high-pressure air pipe vertical section is close to the air outlet, and the outer end section of the high-pressure air pipe transverse section is exposed out of the cutter nozzle cavity. The cold shrinkage degree of the film on the surface of the salivation roller can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of film manufacturing equipment, in particular to an air knife used for film salivation equipment. Background Art

[0002] Figure 1 As shown, the plastic film casting equipment includes an extrusion die 82, a casting roller 81, an air knife, etc., wherein the extrusion die 82 is provided with a narrow extrusion gap, the air knife is provided with a narrow air outlet 60, the air outlet 60 is close to the circumferential surface of the casting roller 81, and the casting roller 81 is provided with a cooling mechanism. During operation, the molten plastic material is extruded from the narrow extrusion gap of the extrusion die 82, flows to the circumferential surface of the casting roller 81, is cooled and shaped into a film 8, and in this process, the air outlet 60 of the air knife blows out airflow to make the film 8 closely adhere to the surface of the casting roller 81, so that the casting roller 81 can cool the film.

[0003] After the plastic material forms a film on the surface of the casting roller, the film is close to the low-temperature casting roller surface, and the newly formed film will shrink when it is cold, and the shrinkage is relatively large. On the other hand, although the air outlet of the wind knife blows out airflow to make the plastic material closely adhere to the surface of the casting roller, the air pressure of the air outlet of the wind knife cannot be too large as a whole (if the overall air pressure is too large, it will affect the stability of the waterfall-like fluid formed by the material drooling, and then affect the stability of the film thickness), and it is difficult to reach a high air pressure (because the air outlet of the wind knife is long, so the overall area of ​​the air outlet of the wind knife is not small, so it is difficult to reach a high air pressure), so the air outlet of the wind knife is difficult to effectively suppress the lateral shrinkage of the film. Utility Model Content

[0004] The utility model aims to overcome the above-mentioned disadvantages and provide a wind knife for film casting equipment, which can reduce the degree of film shrinkage when the film is cooled on the surface of the casting roller.

[0005] The purpose can be achieved according to the following scheme: a wind knife for film casting equipment, comprising an air duct assembly and a knife mouth assembly; the air duct assembly comprises an outer air duct and an inner air duct, the outer air duct is sleeved outside the inner air duct, a plurality of outer ventilation holes are provided on the pipe wall of the outer air duct, and the arrangement direction of each outer ventilation hole is parallel to the axial direction of the outer air duct; a plurality of inner ventilation holes are provided on the pipe wall of the inner air duct, and the arrangement direction of each inner ventilation hole is parallel to the axial direction of the inner air duct; both ends of the inner air duct are connected with air inlet pipes; the knife mouth assembly comprises a left wall plate, a right wall plate, an upper knife plate and a lower knife plate, the left wall plate, the right wall plate, the upper knife plate and the lower knife plate are enclosed to form a knife mouth chamber, the rear end of the knife mouth chamber is connected to the pipe cavity of the outer air duct through the outer ventilation holes, and a long strip air outlet is provided at the front lower end of the knife mouth chamber, and the long direction of the air outlet is defined as the horizontal direction;

[0006] The feature is that: L-shaped high-pressure air ducts are respectively installed on the left and right sides of the knife mouth assembly; each L-shaped high-pressure air duct includes a high-pressure air duct transverse section and a high-pressure air duct vertical section, and the high-pressure air duct transverse section is perpendicular to the high-pressure air duct vertical section; the end opening of the high-pressure air duct vertical section is close to the air outlet, the end opening direction of the high-pressure air duct vertical section is the same as the direction of the air outlet, and the outer end section of the high-pressure air duct transverse section is exposed outside the knife mouth cavity.

[0007] A set of sliding assemblies are respectively installed on the left and right sides of the knife mouth assembly; the transverse sliding assembly on each side includes a transverse partition and a longitudinal partition, the transverse partition is located inside the knife mouth chamber, the inner end of the longitudinal partition is fixedly connected to the rear end of the transverse partition, and the outer end section of the longitudinal partition is exposed outside the knife mouth chamber; the high-pressure air duct on each side is fixedly connected to the transverse partition and longitudinal partition on the corresponding side and slides horizontally synchronously.

[0008] A screw mechanism is also provided for driving the sliding assembly to slide horizontally.

[0009] In this application document, "transverse partition" refers to a plate-like component that divides the knife mouth chamber in the horizontal direction. "Longitudinal partition" refers to a plate-like component that divides the knife mouth chamber in the direction of airflow movement, and the plane where the longitudinal partition is located is perpendicular to the direction of airflow movement in the knife mouth chamber.

[0010] The so-called inner side refers to the side close to the transverse center of the knife mouth chamber in the transverse direction. For the component located on the left side of the wind knife, the inner side is the right side. For the component located on the right side of the wind knife, the inner side is the left side.

[0011] The so-called inner end refers to the end that is close to the transverse center of the knife mouth chamber in the transverse direction.

[0012] The so-called outer end refers to the end that is away from the lateral center of the knife mouth chamber in the horizontal direction. For the component located on the left side of the wind knife, the outer end is the left end. For the component located on the right side of the wind knife, the outer end is the right end.

[0013] The utility model has the following advantages and effects:

[0014] 1. During the operation of the utility model, high-pressure airflow can be input into the left and right L-shaped high-pressure air ducts, and the high-pressure airflow is blown out from the end opening of the vertical section of the high-pressure air duct to form two high-pressure and small airflows and aim at the left and right edge parts of the film on the casting roller, which is equivalent to pressing the left and right ends of the film with force to prevent the left and right ends of the film from shifting due to lateral inner contraction, so that the degree of lateral contraction of the film when it encounters cold on the surface of the casting roller can be effectively reduced.

[0015] 2. The lateral positions of the end points of the two L-shaped high-pressure air ducts on the left and right are adjustable, so they can meet the needs of producing films of different widths.

[0016] 3. The high-pressure airflow is blown out from the end opening of the vertical section of the high-pressure air duct. Since the end opening of the vertical section of the high-pressure air duct is point-shaped, the cross-sectional area of ​​the airflow is small, so it is easy to achieve high pressure; in addition, the high-pressure airflow will only disturb the thickness of the left and right edges of the film, and the thickness of the left and right edges of the film is just the part that needs to be cut off in the end (i.e., the trimming). That is to say, even without the high-pressure airflow, any left and right edges of the film obtained by drooling will need to be cut off due to uneven edges, so the two L-shaped high-pressure air ducts on the left and right of the utility model will not have an adverse effect on the thickness of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the working principle of plastic film casting equipment.

[0018] Figure 2 It is a cross-sectional structural schematic diagram of an embodiment of the utility model.

[0019] Figure 3 yes Figure 2 Schematic diagram of CC section view.

[0020] Figure 4 yes Figure 2 DD cross-sectional view diagram.

[0021] Figure 5 yes Figure 2 EE cross-sectional view diagram.

[0022] Figure 6 yes Figure 2 Schematic diagram of the BB cross-section. DETAILED DESCRIPTION

[0023] Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6As shown, a wind knife for a film casting device of this embodiment includes a wind duct assembly and a knife mouth assembly; the wind duct assembly includes an outer wind duct 1 and an inner wind duct 2, the outer wind duct 1 is sleeved outside the inner wind duct 2, a plurality of outer ventilation holes 10 are opened on the wall of the outer wind duct 1, and the arrangement direction of each outer ventilation hole 10 is parallel to the axial direction of the outer wind duct 1; a plurality of inner ventilation holes 20 are opened on the wall of the inner wind duct 2, and the arrangement direction of each inner ventilation hole 20 is parallel to the axial direction of the inner wind duct 2; both ends of the inner wind duct 2 are connected with air inlet pipes 21; the knife mouth assembly includes a left wall plate 3, a right wall plate 4, an upper knife plate 5 and a lower knife plate 6, which are fixedly connected to the external air duct 1, and the left wall plate 3, the right wall plate 4, the upper knife plate 5 and the lower knife plate 6 are enclosed to form a knife mouth chamber 61, and the rear end of the knife mouth chamber 61 is connected to the tube cavity of the external air duct 1 through the external ventilation hole 10, and the front lower end of the knife mouth chamber 61 is provided with a long strip of air outlet 60, and the long direction of the air outlet 60 is defined as the horizontal direction;

[0024] Figure 2 , Figure 5 , Figure 6 As shown, L-shaped high-pressure air ducts 9 are respectively installed on the left and right sides of the knife mouth assembly; each L-shaped high-pressure air duct 9 includes a high-pressure air duct transverse section 91 and a high-pressure air duct vertical section 92, and the high-pressure air duct transverse section 91 is perpendicular to the high-pressure air duct vertical section 92; the end opening 90 of the high-pressure air duct vertical section 92 is close to the air outlet 60, and the end opening 90 of the high-pressure air duct vertical section faces the same direction as the air outlet 60, and the outer end section of the high-pressure air duct transverse section 91 is exposed outside the knife mouth chamber 61. A set of sliding components are respectively installed on the left and right sides of the knife mouth assembly; the transverse sliding component on each side includes a transverse partition 71 and a longitudinal partition 72, the transverse partition 71 is located inside the knife mouth chamber 61, the inner end of the longitudinal partition 72 is fixedly connected to the rear end of the transverse partition 71, and the outer end section of the longitudinal partition 72 is exposed outside the knife mouth chamber 61; the high-pressure air duct 9 on each side is fixedly connected to the transverse partition 71 and the longitudinal partition 72 on the corresponding side and slides horizontally synchronously. A screw mechanism is also provided for driving the sliding assembly to slide transversely. The screw mechanism includes a screw 73 and a screw handle 74 , wherein the screw 73 is screwed to the transverse partition 71 .

[0025] The working principle of the above embodiment is as follows:

[0026] During operation, the cooling air enters the inner air duct 2 from the air inlet duct 21, enters the outer air duct 1 through the multiple inner air holes 20 of the inner air duct, and enters the knife mouth chamber 61 through the multiple outer air holes 10 of the outer air duct. The cooling air is mixed in the inner air duct 2 and the outer air duct 1 and reaches a basically mixed state along the axial direction. Figure 2 The space area at the lower left corner of the middle knife mouth chamber and the lower right corner of the knife mouth chamber is blocked by the horizontal partition 71 and the longitudinal partition 72. Figure 2There is no airflow passing through the space area at the lower left corner of the middle blade cavity and the lower right corner of the blade cavity, and there is no airflow output from the air outlet of the corresponding section, that is, the airflow is only blown out from the air outlet 60 between the two horizontal partitions 71, and its width is as follows: Figure 6 As shown by the L dimension line.

[0027] At the same time, high-pressure airflow can be input into the left and right L-shaped high-pressure air ducts 9, and the high-pressure airflow is blown out from the end opening 90 of the vertical section of the high-pressure air duct, forming two strong and small airflows and aiming at the left and right edges of the film on the casting roller, which is equivalent to pressing the left and right ends of the film hard to prevent the left and right ends of the film from shifting due to the lateral inward contraction.

[0028] The width of the airflow blown out of the air outlet 60 (eg Figure 6 The L dimension line in the middle shows that the horizontal and vertical directions of the high-pressure air duct 9 are shown in FIG. 1 , and the horizontal and vertical directions of the high-pressure air duct 9 are shown in FIG. 1 . The horizontal and vertical directions of the high-pressure air duct 9 are shown in FIG. 1 , and the horizontal and vertical directions of the high-pressure air duct 9 are shown in FIG. 1 . The horizontal and vertical directions of the high-pressure air duct 9 are shown in FIG. 1 .

Claims

1. A wind knife for film casting equipment, comprising an air duct assembly and a knife mouth assembly; the air duct assembly comprises an outer air duct and an inner air duct, the outer air duct is sleeved outside the inner air duct, a plurality of outer ventilation holes are provided on the wall of the outer air duct, and the arrangement direction of each outer ventilation hole is parallel to the axial direction of the outer air duct; a plurality of inner ventilation holes are provided on the wall of the inner air duct, and the arrangement direction of each inner ventilation hole is parallel to the axial direction of the inner air duct; both ends of the inner air duct are connected with an air inlet duct; the knife mouth assembly comprises a left wall plate, a right wall plate, an upper knife plate and a lower knife plate, the left wall plate, the right wall plate, the upper knife plate and the lower knife plate are surrounded to form a knife mouth chamber, the rear end of the knife mouth chamber is connected to the pipe cavity of the outer air duct through the outer ventilation holes, and a long strip air outlet is provided at the front lower end of the knife mouth chamber, and the long direction of the air outlet is defined as the horizontal direction; it is characterized in that: L-shaped high-pressure air ducts are also installed on the left and right sides of the knife mouth assembly respectively; each L-shaped high-pressure air duct includes a high-pressure air duct transverse section and a high-pressure air duct vertical section, and the high-pressure air duct transverse section is perpendicular to the high-pressure air duct vertical section; the end opening of the high-pressure air duct vertical section is close to the air outlet, and the end opening direction of the high-pressure air duct vertical section is the same as the direction of the air outlet, and the outer end section of the high-pressure air duct transverse section is exposed outside the knife mouth cavity.

2. The air knife for film casting equipment according to claim 1, characterized in that: A set of sliding assemblies are respectively installed on the left and right sides of the knife mouth assembly; the transverse sliding assembly on each side includes a transverse partition and a longitudinal partition, the transverse partition is located inside the knife mouth chamber, the inner end of the longitudinal partition is fixedly connected to the rear end of the transverse partition, and the outer end section of the longitudinal partition is exposed outside the knife mouth chamber; the high-pressure air duct on each side is fixedly connected to the transverse partition and longitudinal partition on the corresponding side and slides horizontally synchronously.

3. The air knife for film casting equipment according to claim 2 is characterized in that: A screw mechanism is also provided for driving the sliding assembly to slide horizontally.

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