A blown film forming device and a rotary die head thereof

Abstract

The present invention relates to the field of film blow molding production technology, and in particular to a blown film forming device and a rotary die head thereof, comprising a shell, a rotating shaft body, a heating assembly and at least four groups of adjustment assemblies, wherein the heating assembly is sleeved on the outer peripheral side of the shell, the rotating shaft body is provided with a ventilation channel, the shell is sleeved on the outer peripheral side of the rotating shaft body, and a gap is provided between the shell and the rotating shaft body, and the shell is provided with a threaded through hole. The adjustment assembly comprises a first screw and a ball, the first screw is connected to the threaded through hole, and the first screw abuts against the rotating shaft body through the ball. Before use, the first screw is rotated to drive the ball to move, thereby pushing the rotating shaft body to the center of a predetermined rotation track. During use, under the limitation of the ball, the rotating shaft body always rotates along the predetermined rotation track, that is, the runout of the rotating shaft body is close to zero, so that the gap size in each direction is always uniform, effectively improving the production accuracy of blown film forming.

Description

Technical Field

[0001] The invention relates to the technical field of film blowing production, in particular to a film blowing forming device and a rotary die head thereof. Background Art

[0002] The principle of blown film molding is to press the melt from the front end of the screw extruder into the die head, so that the melt is extruded into a tube embryo through the die head, and the compressed air introduced from the bottom of the die head is used to blow the tube embryo evenly and freely into a film bubble with a larger diameter. At the same time, the tubular film bubble is longitudinally stretched during the upward traction process, and then flattened by a herringbone plate, pulled by a traction roller, and finally rolled into a tube.

[0003] In existing production, in order to reduce the anisotropy of plastic film, a rotary die is usually used for production. However, during the production process, the rotary die is squeezed by the plastic film, and radial runout is prone to occur, resulting in uneven gaps in all directions, making it difficult to ensure production accuracy. Summary of the Invention

[0004] Based on this, the present invention provides a blown film forming device and a rotary die head thereof capable of reducing radial runout.

[0005] The technical solution of the present invention is: a blown film forming device and a rotary die head thereof, comprising a housing, a rotating shaft body, a heating assembly, and at least four adjustment assemblies, wherein the heating assembly is sleeved on the outer circumference of the housing, the rotating shaft body is provided with an axially extending ventilation channel, the housing is sleeved on the outer circumference of the rotating shaft body, and a gap is provided between the housing and the rotating shaft body, the housing is provided with a threaded through hole extending from the gap to the outer side wall of the housing, the projection surface of the rotating shaft body on the plane in which the radial direction is located is circular, and the threaded through hole extends along the diameter direction of the rotating shaft body;

[0006] The adjusting assembly includes a first screw and a ball mounted on one end of the first screw, the first screw is connected to the threaded through hole, and the first screw abuts against the rotating shaft body through the ball.

[0007] Optionally, the adjustment assembly further includes a spring, a first blind hole is formed at one end of the first screw, one end of the spring is fixedly connected to the inner wall of the first blind hole, and the other end abuts against the sphere.

[0008] Optionally, the sphere includes a first spherical portion and a second spherical portion, the first spherical portion is arranged in the first blind hole, the second spherical portion is arranged outside the first blind hole, and the volume of the first spherical portion is greater than that of the second spherical portion.

[0009] Optionally, the sphere is a ceramic ball.

[0010] Optionally, the first screw rod is a hexagonal bolt, and the head of the first screw rod is arranged outside the housing.

[0011] Optionally, the number of the adjustment components is at least six groups, and the six groups of adjustment components are arranged on the same horizontal plane and are evenly distributed on the outer peripheral side of the shaft body.

[0012] Optionally, a bearing is further included, wherein the bearing is sleeved on the outer peripheral side of the shaft body, and the outer side wall of the bearing abuts against the inner side wall of the shell.

[0013] Another object of this embodiment is to provide a blown film forming device, comprising a feeding system, a driving system and the above-mentioned rotary die head, wherein the feeding system is communicated with the gap, and the driving system is electrically connected to the rotating shaft body.

[0014] Compared with the prior art, the implementation of the present invention has the following beneficial effects:

[0015] The blown film forming device and its rotary die head of the present invention are as follows: before use, the first screw is rotated to drive the ball to move, thereby pushing the rotating shaft body to move to the center of the predetermined rotating track; when in use, under the limitation of the ball, the rotating shaft body always rotates along the predetermined rotating track, that is, the runout of the rotating shaft body is close to zero, so that the gap size in all directions is always uniform, effectively improving the production accuracy of blown film forming. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the blown film forming device described in an embodiment of the present invention.

[0017] Figure 2 The embodiment of the present invention Figure 1 Cross-sectional view along the A-A direction.

[0018] Description of reference numerals:

[0019] 100. Rotary die head,

[0020] 1. Shell,

[0021] 2. Rotating shaft body, 21. Ventilation channel,

[0022] 3. Heating components,

[0023] 4. Adjustment assembly, 41. First screw, 411. First blind hole, 42. Ball, 421. First ball portion, 422. Second ball portion, 43. Spring,

[0024] 5. Gap,

[0025] 6. Bearings,

[0026] 200, feeding system,

[0027] 300, drive system,

[0028] C. Predetermined rotation orbit. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] Furthermore, the present invention uses terms such as "first" and "second" to describe various types of information, but such information should not be limited to these terms. These terms are merely used to distinguish information of the same type from one another. For example, "first" information could also be referred to as "second" information, and similarly, "second" information could also be referred to as "first" information without departing from the scope of the present invention.

[0032] Reference Figure 1 and Figure 2This embodiment provides a rotary die head 100, comprising a housing 1, a rotating shaft body 2, a heating assembly 3, and at least four sets of adjustment assemblies 4. The heating assembly 3 is sleeved on the outer periphery of the housing 1. The rotating shaft body 2 is provided with an axially extending ventilation channel 21. The housing 1 is sleeved on the outer periphery of the rotating shaft body 2, and a gap 5 is provided between the housing 1 and the rotating shaft body 2. The housing 1 is provided with a threaded through hole extending from the gap 5 to the outer wall of the housing 1. The projection of the rotating shaft body 2 on its radial plane is circular, and the threaded through hole extends along the diameter of the rotating shaft body 2. The adjustment assembly 4 includes a first screw 41 and a ball 42 mounted on one end of the first screw 41. The first screw 41 is connected to the threaded through hole, and the first screw 41 abuts against the rotating shaft body 2 via the ball 42. Before use, rotate the first screw 41, and the ball 42 is driven to move by the first screw 41, thereby pushing the shaft body 2 to move to the center of the predetermined rotation track C. During use, under the limitation of the ball 42, the shaft body 2 always rotates along the predetermined rotation track C, that is, the runout of the shaft body 2 is close to zero, so that the size of the gap 5 in all directions is always uniform, effectively improving the production accuracy of blown film molding.

[0033] Better, refer to Figure 1 and Figure 2 In this embodiment, the adjustment assembly 4 further includes a spring 43. A first blind hole 411 is defined at one end of the first screw 41. One end of the spring 43 is fixedly connected to the inner wall of the first blind hole 411, and the other end abuts against the ball 42. When the shaft body 2 applies a force to the ball 42, the spring 43 deforms, causing the ball 42 to move and providing a cushioning force, thereby preventing the shaft body 2 and the ball 42 from colliding and potentially damaging the shaft body 2 and / or the ball 42.

[0034] Better, refer to Figure 1 and Figure 2 In this embodiment, the sphere 42 includes a first sphere portion 421 and a second sphere portion 422. The first sphere portion 421 is disposed within the first blind hole 411, and the second sphere portion 422 is disposed within the first blind hole 411. The volume of the first sphere portion 421 is larger than that of the second sphere portion 422. When the shaft body 2 contacts the sphere 42 during rotation, the first sphere 42 is subjected to a tangential force. The volume of the first sphere portion 421 is larger than that of the second sphere portion 422. At this time, the majority of the volume of the sphere 42 is disposed within the first blind hole 411, reducing the possibility of the sphere 42 flying out.

[0035] Preferably, in this embodiment, the sphere 42 is a ceramic ball. Ceramic balls have good wear resistance and heat resistance, and thus have a longer service life.

[0036] Preferably, in this embodiment, the first screw rod 41 is a hexagonal bolt, and the head of the first screw rod 41 is arranged outside the housing 1. Before use, the operator can use a wrench to easily rotate the first screw rod 41, thereby reducing the operating difficulty of the operator.

[0037] Better, refer to Figure 1 In this embodiment, there are at least six sets of adjustment assemblies 4. These six sets of adjustment assemblies 4 are arranged on the same horizontal plane and evenly distributed around the outer periphery of the shaft body 2, allowing the adjustment assemblies 4 to fully limit the position of the shaft body 2. The six sets of adjustment assemblies 4 are symmetrically arranged in pairs. When the shaft body 2 moves excessively under the action of one set of adjustment assemblies 4, the springs 43 of the opposing adjustment assemblies 4 squeeze the shaft body 2 to form a buffer. The forces exerted on the shaft body 2 by the two opposing sets of adjustment assemblies 4 are aligned, reducing the possibility of the shaft body 2 moving in other directions.

[0038] Better, refer to Figure 1 In this embodiment, the rotary die head 100 also includes a bearing 6, which is sleeved on the outer peripheral side of the shaft body 2, and the outer wall of the bearing 6 abuts against the inner wall of the outer shell 1, which can reduce the possibility of shaking of the shaft body 2 and reduce the friction between the shaft body 2 and the outer shell 1.

[0039] This embodiment also provides a blown film forming apparatus, comprising a feeding system 200, a drive system 300, and the aforementioned rotary die head 100. The feeding system 200 is in communication with the gap 5, and the drive system 300 is electrically connected to the shaft body 2. During use, raw material is injected into the gap 5 via the feeding system 200, and the shaft body 2 is rotated by the drive system 300 to complete production.

[0040] Before use, the blown film forming device and its rotary die head 100 provided in this embodiment rotates the first screw 41, driving the balls 42 to move, thereby pushing the shaft body 2 to the center of a predetermined rotation track C. With the six springs 43 in their natural state, the six first balls 42 are positioned tangentially to the predetermined rotation track C. During use, if the shaft body 2 exhibits radial runout, the adjustment assembly 4 controls the shaft body 2 to continue moving along the predetermined rotation track C. This ensures that the gap 5 remains uniform in all directions during production, effectively improving the production accuracy of the blown film forming process.

[0041] The blown film forming device and the rotary die head 100 of this embodiment have the following beneficial effects:

[0042] 1. Before use, rotate the first screw 41 to drive the ball 42 to move, thereby pushing the shaft body 2 to the center of the predetermined rotation track C. During use, under the limit of the ball 42, the shaft body 2 always rotates along the predetermined rotation track C, that is, the runout of the shaft body 2 is close to zero, so that the size of the gap 5 in all directions is always uniform, effectively improving the production accuracy of the blown film molding.

[0043] 2. When the shaft body 2 applies a force to the ball 42, the spring 43 can deform to move the ball 42 and apply a buffer to the ball 42, thereby avoiding the possibility of damage to the shaft body 2 and / or the ball 42 due to collision between the shaft body 2 and the ball 42.

[0044] 3. When the shaft body 2 contacts the sphere 42 during rotation, the first sphere 42 is subjected to a tangential force. The volume of the first sphere portion 421 is larger than that of the second sphere portion 422. At this time, most of the volume of the sphere 42 is located in the first blind hole 411, which can reduce the possibility of the sphere 42 flying out.

[0045] The four or six groups of adjustment components 4 are symmetrically arranged in pairs. When the shaft body 2 moves too far under the action of one group of adjustment components 4, the springs 43 of the relatively arranged adjustment components 4 squeeze the shaft body 2 to form a buffer. The forces applied by the two relatively arranged adjustment components 4 to the shaft body 2 are in the same straight line, reducing the possibility of the shaft body 2 moving in other directions.

[0046] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A rotary die head, characterized in that: The invention comprises a housing, a rotating shaft body, a heating assembly, and at least four adjustment assemblies, wherein the heating assembly is sleeved on the outer circumference of the housing, the rotating shaft body is provided with an axially extending ventilation channel, the housing is sleeved on the outer circumference of the rotating shaft body, and a gap is provided between the housing and the rotating shaft body, the housing is provided with a threaded through hole extending from the gap to the outer side wall of the housing, the projection surface of the rotating shaft body on the plane in which the radial direction lies is circular, and the threaded through hole extends along the diameter direction of the rotating shaft body; The adjusting assembly includes a first screw and a ball mounted on one end of the first screw, the first screw is connected to the threaded through hole, and the first screw abuts against the rotating shaft body through the ball; Before use, rotate the first screw to drive the ball to move, thereby pushing the shaft body to the center of the predetermined rotation track. During use, under the limitation of the ball, the shaft body always rotates along the predetermined rotation track, that is, the runout of the shaft body is close to zero, so that the gap size in all directions is always uniform.

2. The rotary die head according to claim 1, characterized in that The adjustment component also includes a spring. A first blind hole is formed at one end of the first screw. One end of the spring is fixedly connected to the inner wall of the first blind hole, and the other end abuts against the sphere.

3. The rotary die head according to claim 2, characterized in that The sphere includes a first spherical portion and a second spherical portion. The first spherical portion is disposed in the first blind hole, and the second spherical portion is disposed outside the first blind hole. The volume of the first spherical portion is greater than that of the second spherical portion.

4. The rotary die head according to claim 1, characterized in that The sphere is a pottery ball.

5. The rotary die head according to claim 1, characterized in that The first screw rod is a hexagonal bolt, and the head of the first screw rod is arranged outside the housing.

6. The rotary die head according to claim 1, characterized in that The number of the adjustment components is at least six, and the six groups of adjustment components are arranged on the same horizontal plane and are evenly distributed on the outer circumference of the rotating shaft body.

7. The rotary die head according to claim 1, characterized in that The utility model further comprises a bearing, wherein the bearing is sleeved on the outer peripheral side of the rotating shaft body, and the outer side wall of the bearing abuts against the inner side wall of the shell.

8. A blown film forming device, characterized in that: It comprises a feeding system, a driving system and the rotary die head according to any one of claims 1 to 7, wherein the feeding system is communicated with the gap, and the driving system is electrically connected to the rotating shaft body.

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