Continuous coiling device for plastic bags

Abstract

The invention discloses a continuous coiling device for plastic bags, which belongs to the technical field of belt material coiling and comprises a conveying belt, a suspended section is defined at the tail end of the conveying belt by a first roll shaft and an upstream second roll shaft, and a coiling straight rod is arranged at each of a coiling position at the tail end above the conveying belt and a pre-coiling position at the upstream, the winding straight rod is configured to be capable of unidirectionally transferring from the coiling position to the pre-coiling position along a preset arc-shaped path, and a tensioning roller is arranged on the inner side of the conveying belt. When the winding straight rod transfers and passes through the suspended section, the conveying belt is pressed downwards, the suspended section sinks to form a temporary channel for the suspended section to pass through by utilizing the buffer length provided by the tensioning roller, and meanwhile, the winding straight rod and the conveying belt synchronously and continuously rotate for winding, so that a film roll is effectively prevented from loosening, and the winding quality and the production efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of material winding, and more specifically to a continuous winding device for plastic bags. Background Technology

[0002] The winding of thin-film plastic bags is one of the core links in automated production, which involves efficiently and accurately winding the finished thin-film plastic bags connected by easy-tear seams into finished rolls that meet specifications.

[0003] During the winding process, the straight rod responsible for winding is positioned very close to the conveyor belt in order to wind the broken end of the plastic bag more quickly and stably. During the winding process of each roll of plastic bags, the straight rod responsible for winding needs to be moved from the pre-winding position to the winding position for winding. There is usually more than one straight rod responsible for winding, and all straight rods are driven by a turntable to achieve continuous and uninterrupted winding of the entire winding production line. Specifically, as the straight rod moves from the pre-winding point to the winding point, a new idle straight rod will be added to the pre-winding point for the next round of winding.

[0004] Therefore, the transfer process of the winding rod will inevitably interfere with the conveyor belt below. During the process of forcibly pressing down on the conveyor belt and transferring it, an all-directional frictional force will be applied to the plastic bag roll in the pre-wound state. This frictional force will cause the plastic bag roll to tend to loosen and unwind.

[0005] In summary, for the current high-speed continuous winding of thin-film plastic bags, how to ensure the effective and stable transfer of the plastic bag roll with weak interlayer adhesion during initial winding is a problem that needs to be solved. Summary of the Invention

[0006] The purpose of this invention is to provide a continuous rolling device for plastic bags to solve the problems of roll transfer and anti-unwinding during the rolling process of film plastic bags in the prior art.

[0007] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: A continuous roll-forming device for plastic bags includes: A conveyor belt is used to transport continuous plastic film bags. The plastic film bags are attached to the surface of the conveyor belt. A winding position is set at the top of the conveyor belt, and a pre-winding position is set upstream of the winding position in the conveying direction. The first roller is located at the end of the conveyor belt, where the conveyor belt turns back. The second roller is located upstream of the first roller. The conveyor belt passes through the second roller and the first roller in sequence to form a suspended section between the first roller and the second roller. A winding rod, located above the conveyor belt and parallel to the width direction of the conveyor belt, is used to wind a continuous film plastic bag on the conveyor belt. The winding rod is configured to be unidirectionally transferred from the winding position to the pre-winding position along a preset arc path. The tension roller, located inside the conveyor belt, is configured to abut against the inner surface of the conveyor belt from the inside out under the action of elastic force, so that the conveyor belt has a buffer redundancy length under the downward pressure applied by the winding rod. The winding rod moves along an arc-shaped path and applies downward pressure to the suspended section when it passes through it, so as to form a channel for the winding rod to pass through by means of the buffer redundancy length of the conveyor belt. The winding speed and direction of the winding rod are matched with the running speed and direction of the conveyor belt so that the winding rod can cooperate with the conveyor belt to continuously wind up the plastic film bag during the above-mentioned avoidance process.

[0008] Furthermore, the second roller is located below the pre-winding position, and a first lifting cylinder is provided below the second roller. The telescopic end of the first lifting cylinder acts on the second roller to lift the conveyor belt in the entire width direction, so that the head end of the film plastic bag on the conveyor belt contacts the winding rod in the pre-winding position. The winding rod is used to wind up the head end of the film plastic bag in contact with it and pre-wind it.

[0009] Furthermore, the second roller is mounted on a second tilting frame, which is rotatably positioned below the conveyor belt, and the second roller is rotatably positioned at the free end of the second tilting frame; The telescopic end of the first lifting cylinder applies force to the free end of the second tilting frame, causing the second roller to be raised or lowered by rotating around the rotating connection of the second tilting frame.

[0010] Furthermore, a second lifting cylinder is provided below the first roller shaft. The telescopic end of the second lifting cylinder acts on the first roller shaft so that the first roller shaft can drive the end of the conveyor belt to be raised or lowered.

[0011] Furthermore, an H-shaped bracket is provided on the inner side of the end of the conveyor belt, with the first roller and the second roller respectively located at both ends of the H-shaped bracket, and both the first roller and the second roller can rotate freely; A support base for supporting the rotatable connection in the middle is fixedly installed at the bottom of the H-shaped bracket. The support base has a base plate for hinged to the lower end of the second lifting cylinder. The upper end of the second lifting cylinder is hinged to the end of the H-shaped bracket with the first roller shaft.

[0012] Furthermore, a first crossbar is suspended at one end of the H-shaped support where the second roller shaft is located. The axial direction of the first crossbar is parallel to the width direction of the conveyor belt. The lower end of the first lifting cylinder is hinged to the first crossbar. The second tilting frame is axially connected to the end of the H-shaped support where the first crossbar is located. The upper end of the first lifting cylinder acts on the second roller shaft to make the second tilting frame rotate relative to the H-shaped support to achieve its lifting action. The second roller is always positioned higher than the top surface of the H-shaped support to prevent the H-shaped support from contacting the conveyor belt.

[0013] Furthermore, the telescopic end of the first lifting cylinder is provided with a V-shaped bracket that lifts the second roller shaft upwards, and rollers that roll against the second roller shaft are provided on the two inner walls of the open end of the V-shaped bracket.

[0014] Furthermore, the first roller is located below the winding position. During the continuous winding of the plastic film bag by the winding rod in the winding position, the conveyor belt at the location of the first roller is lower than the conveyor belt at the location of the second roller, so that a gap is formed between the winding rod in the winding position and the conveyor belt below. The gap prevents the plastic film bag roll, which is in the winding process and whose roll diameter is gradually increasing, from contacting the conveyor belt.

[0015] The beneficial effects of the present invention are as follows: By setting an overhanging section formed by the first and second rollers at the end of the conveyor belt and using the tension roller to provide buffer redundancy, the present invention enables the winding rod to actively press down on the conveyor belt to form a temporary clearance channel when it is transferred from the pre-winding position to the winding position, thereby ensuring the smooth operation of the mechanism; at the same time, since the winding rod rotates and winds up synchronously with the conveyor belt throughout the clearance process, the problem of initial film roll loosening caused by the transfer process is avoided. Attached Figure Description

[0016] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention in its first working state; Figure 2 for Figure 1 A partial front view; Figure 3 This is a three-dimensional structural diagram of the present invention in its second working state; Figure 4 for Figure 2 A partial front view; Figure 5 This is a three-dimensional structural diagram of the present invention in its third working state; Figure 6 for Figure 3 A partial front view; Figure 7 This is a three-dimensional structural diagram of the present invention in its fourth working state; Figure 8 for Figure 4 A partial front view; Figure 9 This is a planar cross-sectional view of the present invention during the tearing process; Figure 10 for Figure 9 Enlarged schematic diagram of the structure at point A in the diagram; Figure 11 This is a three-dimensional structural diagram of the continuous winding device of the present invention; The labels in the diagram represent the following: 1-Conveyor belt; 2-Turntable; 3-Winding straight rod; 4-Drive cabinet; 5-Follow-up pressure roller; 6-Support shaft; 7-Protective cover; 7a-Guide groove; 7b-Winding channel; 8-Second roller shaft; 9-First tilting frame; 10-First lifting cylinder; 11-H-type bracket; 12-First roller shaft; 13-Support seat; 14-Second lifting cylinder; 15-Tension roller; 16-First crossbar; 17-Rope pressing roller; 18-V-type bracket; 19-Roller; 20-Second tilting frame; 21-Air duct; 22-Air pipe assembly; 23-Rope-type pressure conveyor belt. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] First embodiment: Reference Figure 1 and Figure 11 This embodiment mainly provides a continuous rolling device for plastic bags, focusing on how to achieve continuous rolling, specifically including: Conveyor belt 1 is used to transport continuous film plastic bags. The film plastic bags are attached to the surface of conveyor belt 1. A winding position is provided above the conveyor belt 1, and a pre-winding position is provided upstream of the winding position in the conveying direction. The first roller 12 is located at the end of the conveyor belt 1, and the conveyor belt 1 turns back at the first roller 12; The second roller 8 is located upstream of the first roller 12. The conveyor belt 1 passes through the second roller 8 and the first roller 12 in sequence to form a suspended section between the first roller 12 and the second roller 8. The winding rod 3 is located above the conveyor belt 1 and parallel to the width direction of the conveyor belt 1. The winding rod 3 is used to wind the continuous film plastic bag on the conveyor belt 1. The winding rod 3 is configured to be able to move unidirectionally from the winding position to the pre-winding position along a preset arc path. Tensioner roller 15 is located inside the conveyor belt 1. Tensioner roller 15 is configured to abut against the inner surface of the conveyor belt 1 from the inside out under the action of elastic force, so that the conveyor belt 1 has a buffer redundancy length under the downward pressure applied by the winding rod 3. The winding rod 3 moves along an arc-shaped path and applies downward pressure to the suspended section when it passes through the suspended section, so as to form a channel for the winding rod 3 to pass through by means of the buffer redundancy length of the conveyor belt 1. The winding speed and direction of the winding rod 3 are matched with the running speed and direction of the conveyor belt 1 so that the winding rod 3 can cooperate with the conveyor belt 1 to continuously wind up the plastic film bag during the above-mentioned avoidance process.

[0020] The core of this structure lies in the fact that by setting up a suspended section and a tension roller 15, the end area of ​​the conveyor belt 1 is given a certain degree of elastic deformation capability. When the winding rod 3 rotates from the pre-winding position to the winding position, it presses down on this suspended section. The buffer redundancy provided by the tension roller 15 allows the conveyor belt 1 to sink accordingly, temporarily forming a channel for the winding rod 3 and the pre-winding roll on it to pass smoothly. More importantly, the winding rod 3 does not stop rotating during this period, but maintains a winding action that matches the speed of the conveyor belt 1, thereby ensuring that the film plastic bag is always in a taut state. This effectively avoids the problem of loosening and unwinding caused by pauses or interference during the transfer process, achieving a seamless connection from pre-winding to winding.

[0021] More specifically, the turntable 2 drives the winding rod 3 to perform a circumferential transfer motion. The aforementioned preset arc path is the part of the circumferential motion path of the turntable 2 driving the winding rod 3 in the second embodiment that overlaps with the conveyor belt 1.

[0022] Furthermore, to achieve the integration of structure and function, the second roller shaft 8 is located below the pre-winding position, and a first lifting cylinder 10 is provided below the second roller shaft 8. The telescopic end of the first lifting cylinder 10 acts on the second roller shaft 8 to lift the conveyor belt 1 in the entire width direction, so that the head end of the film plastic bag on the conveyor belt 1 contacts the winding rod 3 in the pre-winding position. The winding rod 3 is used to wind up and pre-wind the head end of the film plastic bag in contact with it.

[0023] In this way, the second roller 8 serves both as the boundary for forming the suspended section and as the fulcrum for performing the pre-rolling and lifting action, thus simplifying the equipment structure.

[0024] More importantly, this structure cleverly solves the initial startup problem of the entire production operation. Specifically, when the production line is started for the first time or a new roll of material is replaced, there is no "tear-resistant seam" slitting between the front and rear ends. At this time, the initial end winding can be completed independently using this device. When the initial end of the continuous film plastic bags is conveyed to the pre-winding position, the first lifting cylinder 10 is activated, lifting the second roller 8 and thus raising the conveyor belt 1, so that the initial end of the film (i.e., the material head) abuts against the rotating winding rod 3, thereby being reliably wound up to form the first pre-wound roll. Once the first roll pre-winding is completed, the equipment can seamlessly switch to the subsequent continuous automated cycle operation of "speed difference slitting-pre-winding-transfer-winding". Therefore, this design, through functional reuse, avoids setting up an additional complex startup "head-threading" mechanism, which not only simplifies the equipment structure and reduces costs, but also improves the automation and reliability of production startup.

[0025] To make the lifting action of the second roller 8 more stable and controllable, the second roller 8 is set on a second tilting frame 20, which is rotatably set below the conveyor belt 1, and the second roller 8 is rotatably set at the free end of the second tilting frame 20. The telescopic end of the first lifting cylinder 10 applies force to the free end of the second tilting frame 20, causing the second roller shaft 8 to be raised or lowered by rotating around the rotational connection of the second tilting frame 20.

[0026] Compared to direct lifting, this lever-type lifting method provides more stable support and more precise displacement control.

[0027] In addition, to achieve more flexible adjustment of the end posture of the conveyor belt 1, a second lifting cylinder 14 is provided below the first roller 12. The telescopic end of the second lifting cylinder 14 acts on the first roller 12 so that the first roller 12 can drive the end of the conveyor belt 1 to be raised or lowered.

[0028] Therefore, by independently controlling the height of the first roller 12 and the second roller 8, the shape of the suspended section can be precisely constructed and adjusted.

[0029] To integrate the above rollers and drive mechanism, a preferred structural scheme is proposed: an H-shaped bracket 11 is provided on the inner side of the end of the conveyor belt 1, and the first roller 12 and the second roller 8 are respectively located at both ends of the H-shaped bracket 11, and both the first roller 12 and the second roller 8 can rotate freely; A support base 13 for supporting the rotatable connection in the middle is fixedly installed below the H-shaped bracket 11. The support base 13 has a base plate for hinged to the lower end of the second lifting cylinder 14. The upper end of the second lifting cylinder 14 is hinged to the end of the H-shaped bracket 11 with the first roller shaft 12.

[0030] Thus, the H-shaped bracket 11 acts like a seesaw, and by driving one end (the end where the first roller 12 is located) to rise and fall through the second lifting cylinder 14, the overall posture of the end of the conveyor belt 1 can be adjusted.

[0031] Based on this, in order to achieve independent lifting and lowering control of the second roller shaft 8, a first crossbar 16 is suspended at the end of the H-shaped bracket 11 where the second roller shaft 8 is located. The axial direction of the first crossbar 16 is parallel to the width direction of the conveyor belt 1. The lower end of the first lifting cylinder 10 is hinged to the first crossbar 16. The second tilting frame 20 is axially connected to the end of the H-shaped bracket 11 where the first crossbar 16 is located. The upper end of the first lifting cylinder 10 acts on the second roller shaft 8 to make the second tilting frame 20 rotate relative to the H-shaped bracket 11 to achieve its lifting and lowering action, thereby driving the second roller shaft 8 to lift and lower. To avoid motion interference, the position of the second roller 8 is always higher than the top surface of the H-shaped support 11, so as to avoid the H-shaped support 11 from contacting the conveyor belt 1.

[0032] To optimize the interaction between the first lifting cylinder 10 and the second roller shaft 8, reduce friction, and ensure smooth force transmission, the telescopic end of the lifting cylinder is provided with a V-shaped bracket 18 that lifts the second roller shaft 8 upward. Rollers 19 that roll against the second roller shaft 8 are provided on the two inner walls of the open end of the V-shaped bracket 18.

[0033] When the cylinder extends, the V-shaped bracket 18 smoothly pushes the roller 19, which rolls along the surface of the second roller shaft 8, efficiently converting the linear motion into the lifting motion of the second roller shaft 8.

[0034] Finally, to address potential interference issues during the winding process, the first roller 12 is positioned below the winding position. During the continuous winding of the plastic film bag by the winding rod 3 in the winding position, the conveyor belt 1 at the location of the first roller 12 is lower than the conveyor belt 1 at the location of the second roller 8. This creates a natural downward slope at the end of the conveyor belt 1, ensuring a necessary gap between the winding rod 3 in the winding position and the conveyor belt 1 below. This gap prevents the bottom of the plastic film bag roll from rubbing or colliding with the surface of the conveyor belt 1 as the roll diameter gradually increases during the winding process, thus guaranteeing a smooth winding process and the quality of the final finished roll.

[0035] Second embodiment: Based on the first embodiment, this embodiment mainly realizes the continuous winding process of the thin film plastic bag connected by the easy-tear seam, as well as the disconnection technology during the winding process.

[0036] Reference Figures 1 to 9 The winding device for the plastic film bag mainly includes: Conveyor belt 1 is used to transport film plastic bags connected by easy-tear seams. The film plastic bags are attached to the surface of conveyor belt 1. The end of conveyor belt 1 is set as a roll-up position, and a pre-roll position is set upstream of the roll-up position in the conveying direction. Turntable 2 is located at one end of conveyor belt 1, and the axis of turntable 2 is parallel to the width direction of conveyor belt 1. The winding rod 3 is arranged circumferentially on the turntable 2 with multiple fixed-point shaft connections. The winding rod 3 is parallel to the width direction of the conveyor belt 1. After each rotation of the turntable 2, there is a winding rod 3 at the coiling position and the pre-coiling position. A lifting device is installed at the bottom of the conveyor belt 1. The actuating end of the lifting device can lift the conveyor belt 1 upward in the entire width direction so that the plastic film bag on the conveyor belt 1 contacts the winding rod 3 in the pre-wound position. The lifting device's actuating end is located between and near the winding position, so as to form a tearing area in the area between the winding position and the pre-winding position, and relatively close to the winding rod 3 in the pre-winding position. When the lifting device lifts the conveyor belt 1, the rotation speed of the winding rod 3 at the pre-winding position is reduced or stopped instantaneously to create a speed difference between the conveyor belt 1 and the winding rod 3, so that the easy-tear seam located in the tearing area is torn open. When the tear seam is torn, the winding rod 3 located in the pre-wound position pre-wound the broken end of the plastic film bag, and then the turntable 2 rotates so that the winding rod 3 in the pre-wound position rotates to the roll position. During this process, the movement path of the winding rod 3 is the aforementioned preset arc path.

[0037] This embodiment primarily involves creating two winding positions along the roll-up conveying path of the plastic film bag. Pre-winding is performed simultaneously with breaking the tear seam of the plastic bag, eliminating the need to wait for the broken end of the plastic bag to be conveyed to the end roll-up position before winding. This avoids the problem of the broken end of the plastic bag shifting during the transmission process or shifting after breakage, which would make it difficult to wind.

[0038] Furthermore, this embodiment uses tensile force to achieve the breakage, especially at the upstream end of the breakage, the winding rod 3 abuts against the film plastic bag, so that the plastic bag can be directly wound at the same time as the breakage, and even if the plastic bag is deviated at the breakage, it will not affect its winding.

[0039] After winding, the winding rod 3 rotates to the coiling position at the end of the conveyor belt 1. At the pre-winding position, there is a new empty winding rod 3, and then it waits for the next winding cycle.

[0040] The winding rod 3 is used to both wind the plastic film bag and tear the easy-tear seam of the plastic film bag. It can also prevent the plastic film bag from shifting after being broken, thus ensuring the winding of the plastic film bag.

[0041] This embodiment does not limit the specific implementation of how the thin film plastic bag can be rolled up by the straight rod 3 on the conveyor belt 1.

[0042] First, when the conveyor belt 1 is lifted, the winding rod 3 at the pre-winding position is located on the inclined surface of the lifting position. Under the rotation of the winding rod 3, the film plastic bag can be wound.

[0043] In addition, static electricity can be generally applied to the plastic film bag before it enters the pre-winding position so that the plastic film bag can be more stably adsorbed and wound at the pre-winding position.

[0044] Specifically, the instantaneous reduction or cessation of the rotation speed of the winding rod 3 means that when it is necessary to disconnect, the rotation speed of the winding rod 3 is reduced or stopped for a short time, so that the plastic film bag generates a tensile force between the pre-wound position and the rolled position. At the same time, the easy-tear seam is easier to tear when it is lifted up, thus ensuring that the breakage location is the easy-tear seam in the tear area, rather than other easy-tear seams outside the tear area.

[0045] More specifically, the tear point of the aforementioned easy-tear seam is set in the tear zone, relatively close to the winding rod 3 in the pre-winding position, so that the broken end of the plastic bag is located near the winding rod 3 during pre-winding, thereby improving the success rate of pre-winding.

[0046] Preferably, the distance between the pre-winding position and the winding position is equal to or less than the length of a plastic bag, so that there is only one tear seam between the pre-winding position and the winding position to avoid inaccurate breakage. Of course, the lifting device configuration based on this embodiment is not limited to the distance between the pre-winding position and the winding position.

[0047] In this embodiment, the rotational speed of the winding rod 3, the conveying speed of the conveyor belt 1, and the distance between each component are all known. Therefore, ensuring that each component performs its actions when the tear seam is in the tearing area can be achieved through system settings.

[0048] Of course, it can also be achieved through visual detection; this implementation method does not limit the specific implementation method.

[0049] To ensure greater stability and facilitate easier tearing of the tear zone, a follower pressure roller 5 is provided between the winding position and the lifting position. The follower pressure roller 5 is close to the lifting position. When the conveyor belt 1 is lifted, the follower pressure roller 5 and the winding rod 3 at the pre-winding position abut against the plastic film bag on the surface of the conveyor belt 1, so that the tear zone is located between the follower pressure roller 5 and the winding rod 3 at the pre-winding position. The follower roller 5 can rotate freely so that it rotates along with the conveyance of the plastic film bag when it comes into contact with the plastic film bag.

[0050] The main function of the follower pressure roller 5 is to work with the winding rod 3 at the pre-winding position to stably abut against the plastic film at both ends of the tear seam, making it easier to break the tear seam. More specifically, when the follower pressure roller 5 abuts against the conveyor belt 1, it forms a pressure on one end of the tear seam in the tear area, while the abutment between the winding rod 3 at the pre-winding position and the conveyor belt 1 forms a pressure on the other end of the tear seam. With this foundation of pressure support on both sides, the tear seam can be stably and more easily broken. Due to the addition of the follower pressure roller 5, the tearing area is restricted from the original roll position between the pre-winding position to the area between the follower pressure roller 5 and the winding rod 3 at the pre-winding position.

[0051] In this embodiment, the follower roller 5 can be independently and stably positioned above the conveyor belt 1, able to abut against the plastic film bag when the conveyor belt 1 is lifted, and not in contact with the plastic film bag when the conveyor belt 1 is not lifted. However, the following minor problems exist: First, the friction between the follower roller 5 and the plastic film bag during the contact and transmission process will generate static electricity, which will affect the conveying of the plastic film bag when it is not lifted due to the static electricity generated by friction.

[0052] Secondly, if the distance between the follower roller 5 and the plastic film bag is set far, then there will be higher requirements for the lifting distance of the conveyor belt 1.

[0053] In this regard, a preferred embodiment of the follower pressure roller 5 is further provided below: The follower pressure roller 5 is set on a first tilting frame 9, which is rotatably set on both sides of the conveyor belt 1, allowing the follower pressure roller 5 to rotate freely. The first flipping frame 9 flips towards the rolling position when the lifting device lifts it up, and the follower pressure roller 5 abuts against the film plastic bag on the conveyor belt 1 after being lifted up.

[0054] The first tilting frame 9 can be rotatably connected to both sides of the conveyor belt 1 by a drive device (such as a motor), and its movement timing is controlled by the system.

[0055] In addition to solving the above problems, the lifting of the conveyor belt 1 only needs to consider the factors that are more conducive to the breaking of the plastic film bag and the winding of the broken end of the plastic bag by the winding rod 3 which is most conducive to the pre-winding position, without having to consider the influence of the follower pressure roller 5.

[0056] Moreover, the aforementioned arrangement of the follower roller 5 limits the squeezing force between it and the plastic film bag to the lifting range of the conveyor belt 1, and the conveyor belt 1 itself has a certain deformation capacity, resulting in a loose contact between the follower roller 5 and the plastic film bag.

[0057] By rotating the first flipping frame 9, the follower pressure roller 5 can be made to adhere more tightly to the plastic film bag, and the squeezing force between the two can be controlled by controlling the flipping amplitude of the first flipping frame 9.

[0058] Considering that the pre-winding is easily affected by the external environment, the rotation connection of the first flipping frame 9 is located upstream of the conveying direction of the pre-winding position; a protective cover 7 is provided at one end of the first flipping frame 9 facing the surface of the conveyor belt 1 after flipping, and the protective cover 7 can relatively close the pre-winding position and the tear area.

[0059] This embodiment also generally includes a winding rod 3 drive device, a turntable 2 drive device and a control system. Each winding rod 3 is connected to a winding rod 3 drive device, and the above devices are integrated on a drive cabinet 4 located on one side of the end of the conveyor belt 1.

[0060] The control system connects the turntable 2 drive device, the winding rod 3 drive device, and the lifting device. After each winding is completed, the control system controls the driving lifting device to lift the conveyor belt 1, and at the same time reduces the speed of the winding rod 3 at the pre-winding position or stops the rotation of the winding rod 3 momentarily through the winding rod 3 drive device, so as to form a speed difference between the conveyor belt 1 and the winding rod 3, so that the easy-tear seam in the tearing area is torn open and the original speed is restored.

[0061] To further improve the stability of the pre-winding action after the tear seam breaks, and to enable the tear seam to adhere to the corresponding pre-winding rod 3 more quickly after being torn, an air channel 21 facing the tear area can be provided on the protective cover 7. The air channel 21 is connected to an air source and is used to blow air after the tear seam is torn, so that the broken end of the plastic bag is blown to adhere to the pre-winding rod 3 at the pre-winding position in a semi-enclosed form.

[0062] More specifically, there are several air channels 21, which are evenly arranged along the width of the protective cover 7. All air channels 21 are connected to the air source through an air pipe group 22. The blowing action of the air channels 21 is controlled by the control system. The blowing outlet of the air channel 21 is located in the tearing section closer to the follower pressure roller 5. In this way, if the broken end of the easy tear is not pre-wound in time, as the broken end arrives, the airflow blown out by the air channel 21 will also lift the end of the plastic bag upward, so as to help the broken end of the plastic bag be blown into a semi-enclosed form and attached to the winding rod 3 at the pre-wound position.

[0063] Although the pre-winding process is not long, the pre-wound plastic bag is located in a cylindrical shape on the winding rod 3, and the diameter of the cylinder will gradually increase. To prevent frictional contact between the plastic bag cylinder and the protective cover 7 during the pre-winding process, a guide groove 7a is formed on the protective cover 7, which is coaxial with the winding rod 3 at the pre-winding position. A winding channel 7b is formed between the guide groove 7a and the winding rod 3 at the pre-winding position, so that the broken end of the film plastic bag can be partially wrapped on the winding rod 3 during the pre-winding process, and the film plastic bag roll with a gradually increasing cylinder diameter can be accommodated.

[0064] With the assistance of the air passage 21, the broken end of the plastic bag will enter the winding and be wound around the winding rod 3 along the guide groove 7a.

[0065] Furthermore, in order to make the blowing direction of the air passage 21 more conducive to the lifting of the plastic bag end, the follower pressure roller 5 is axially connected to the bottom of the protective cover 7 and located on the side of the guide groove 7a away from the rotational connection of the first flipping frame 9. Air passage 21 is formed on the protective cover 7 and is located between the follower roller 5 and the guide groove 7a. The tearing area is arc-shaped when the follower roller 5 and the winding rod 3 at the pre-winding position jointly abut against the conveyor belt 1. The blowing direction of air passage 21 is towards this arc segment.

[0066] Thus, when the tear seam breaks, the broken end of the plastic bag will move along the tear section of the arc segment toward the position of the follower pressure roller 5 without being pre-wound in time, until it is lifted by the airflow blowing in the direction of the arc segment and then attached to the winding rod 3 through the guide groove 7a, thereby preventing the broken end of the plastic bag from leaving and going to the roll position without being pre-wound.

[0067] Regarding the rotational connection method of the first flipping frame 9, this embodiment does not limit the specific implementation method, but provides a relatively high degree of integration. A rope pressing roller 17 is provided at the upstream position of the pre-winding position, which is coaxially rotating with the rotational connection of the first flipping frame 9. The rope pressing roller 17 is in close contact with the film plastic bag on the conveyor belt 1.

[0068] More specifically, the pressure roller 17 is part of a rope-type pressure conveyor belt 23. A support shaft 6 that can rotate freely relative to the center of the pressure roller 17 is provided. One end of the support shaft 6 can be directly connected to the nearby drive cabinet 4 at a fixed point. The two sides of the first tilting frame 9 are fixedly sleeved on the two ends of the support shaft 6. The drive device of the first tilting frame 9 is integrated in the drive cabinet 4 to drive the support shaft 6 to rotate. While being able to drive the first tilting frame 9 to rotate, it does not affect the rotation drive of the rope-type pressure conveyor belt 23 on the pressure roller 17.

[0069] The rotation method of the rope pressing roller 17 can be either driven by the rope pressing conveyor belt 23 or rotate with the conveyor belt 1. This embodiment does not limit this.

[0070] Regarding the lifting method of the conveyor belt 1 near the pre-winding position, this embodiment provides a specific implementation method. The lifting device includes a first lifting cylinder 10 and a second roller shaft 8. The second roller shaft 8 is rotatably connected to the telescopic end of the first lifting cylinder 10. The second roller shaft 8 can rotate freely and its length direction is parallel to the width direction of the conveyor belt 1. The first lifting cylinder 10 is used to lift the second roller shaft 8 to lift the conveyor belt 1 so that the film plastic bag contacts the winding rod 3 at the pre-winding position in the lifted position.

[0071] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of the embodiments of the present invention.

Claims

1. A continuous roll-forming device for plastic bags, characterized in that, include: A conveyor belt (1) is used to transport continuous film plastic bags, the film plastic bags being attached to the surface of the conveyor belt (1), a winding position is provided above the conveyor belt (1), and a pre-winding position is provided upstream of the winding position in the conveying direction. The first roller (12) is located at the end of the conveyor belt (1), and the conveyor belt (1) folds back at the first roller (12); The second roller (8) is located upstream of the first roller (12), and the conveyor belt (1) passes through the second roller (8) and the first roller (12) in sequence to form a suspended section between the first roller (12) and the second roller (8); A winding rod (3) is located above the conveyor belt (1) and parallel to the width direction of the conveyor belt (1). The winding rod (3) is used to wind a continuous film plastic bag on the conveyor belt (1). The winding rod (3) is configured to be unidirectionally transferred from the winding position to the pre-winding position along a preset arc path. Tensioner roller (15), located inside the conveyor belt (1), is configured to abut against the inner surface of the conveyor belt (1) from the inside out under the action of elastic force, so that the conveyor belt (1) has a buffered redundant length under the downward pressure applied by the winding rod (3). The winding rod (3) moves along the arc path and applies downward pressure to the suspended section when it passes through the suspended section, so as to form a channel for the winding rod (3) to pass through by means of the buffer redundancy length of the conveyor belt (1). The winding speed and direction of the winding rod (3) are matched with the running speed and direction of the conveyor belt (1) so that the winding rod (3) can cooperate with the conveyor belt (1) to continuously wind up the plastic film bag during the above-mentioned avoidance process.

2. The continuous roll-forming device for plastic bags according to claim 1, characterized in that, The second roller (8) is located below the pre-winding position. A first lifting cylinder (10) is provided below the second roller (8). The telescopic end of the first lifting cylinder (10) acts on the second roller (8) to lift the conveyor belt (1) in the entire width direction so that the head end of the film plastic bag on the conveyor belt (1) contacts the winding rod (3) in the pre-winding position. The winding rod (3) is used to wind up and pre-wind the head end of the film plastic bag that is in contact with it.

3. The continuous roll-forming device for plastic bags according to claim 2, characterized in that, The second roller (8) is mounted on a second tilting frame (20), which is rotatably mounted below the conveyor belt (1), and the second roller (8) is rotatably mounted at the free end of the second tilting frame (20); The telescopic end of the first lifting cylinder (10) applies force to the free end of the second tilting frame (20), causing the second roller (8) to be lifted or lowered by rotating around the rotational connection of the second tilting frame (20).

4. A continuous roll-forming device for plastic bags according to claim 3, characterized in that, A second lifting cylinder (14) is provided below the first roller (12). The extension end of the second lifting cylinder (14) acts on the first roller (12) so that the first roller (12) can drive the end of the conveyor belt (1) to be raised or lowered.

5. A continuous roll-forming device for plastic bags according to claim 4, characterized in that, An H-shaped bracket (11) is provided on the inner side of the end of the conveyor belt (1). The first roller (12) and the second roller (8) are respectively located at both ends of the H-shaped bracket (11). Both the first roller (12) and the second roller (8) can rotate freely. A support base (13) for supporting the rotatable connection in the middle is fixedly provided below the H-shaped bracket (11). The support base (13) has a base plate for hinged to the lower end of the second lifting cylinder (14). The upper end of the second lifting cylinder (14) is hinged to one end of the H-shaped bracket (11) with the first roller shaft (12).

6. A continuous roll-forming device for plastic bags according to claim 5, characterized in that, A first crossbar (16) is suspended at one end of the H-shaped bracket (11) where a second roller shaft (8) is provided. The axial direction of the first crossbar (16) is parallel to the width direction of the conveyor belt (1). The lower end of the first lifting cylinder (10) is hinged to the first crossbar (16). The second tilting frame (20) is axially connected to one end of the H-shaped bracket (11) where the first crossbar (16) is provided. The upper end of the first lifting cylinder (10) acts on the second roller shaft (8) to make the second tilting frame (20) rotate relative to the H-shaped bracket (11) to achieve lifting action. The position of the second roller (8) is always higher than the top surface of the H-shaped bracket (11) to avoid the H-shaped bracket (11) from contacting the conveyor belt (1).

7. A continuous roll-forming device for plastic bags according to claim 1, characterized in that, The telescopic end of the lifting cylinder is provided with a V-shaped bracket (18) that lifts the second roller shaft (8) upward. The two inner walls of the open end of the V-shaped bracket (18) are provided with rollers (19) that roll against the second roller shaft (8).

8. A continuous roll-forming apparatus for plastic bags according to any one of claims 1 to 7, characterized in that, The first roller (12) is located below the winding position. During the continuous winding of the film plastic bag by the winding rod (3) in the winding position, the conveyor belt (1) at the position of the first roller (12) is lower than the conveyor belt (1) at the position of the second roller (8), so that a gap is formed between the winding rod (3) in the winding position and the conveyor belt (1) below. The gap prevents the film plastic bag roll, which is in the winding process and whose roll diameter is gradually increasing, from contacting the conveyor belt (1).

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