Packaging bag production method and folding device

Abstract

The invention discloses a packaging bag production method and a folding device, and belongs to the technical field of packaging bag production equipment.The packaging bag production device comprises a rack, a plurality of conveying rollers are rotationally connected to the rack, the rack is provided with a steering assembly and a folding assembly, and the steering assembly and the folding assembly each comprise a closing piece; the folding assembly is used for extruding the surfaces of the two sides of a material to form a plurality of bending areas, and the steering assembly is used for adjusting the included angle of the projection of the connecting line of the two ends away from each other after the material expands and the projection of the connecting line of two force application points, extruded by the folding assembly, of the material on the plane perpendicular to the path of the material passing through the folding assembly. According to the packaging bag production method and the folding device, the folding device is applied to a production line of the four-edge-sealed packaging bag, so that the style of the four-edge-sealed packaging bag produced by processing a casting film produced by a casting machine is consistent with that of the four-edge-sealed packaging bag produced by a blown film, the production line is shorter, and the production efficiency is improved. And the efficiency is higher due to the printing convenience of the cast film.

Description

Technical Field

[0001] The present invention relates to the technical field of packaging bag production equipment, and specifically relates to a production method and folding device for packaging bags. Background Art

[0002] Producing packaging bags with patterns printed on the surface usually requires processes such as film making, printing, and slitting. Among them, the four-side sealed packaging bag has two sealing edge structures on both sides. When the packaging bag is unfolded along the thickness direction, the corner positions on both sides of the pattern surface will not be distorted due to traction, making the pattern on the surface of the packaging bag visually flatter.

[0003] The existing cast film can be produced by a casting machine using a process of single-sided printing and then folding, which shortens the length of the production line of the printing process, thereby reducing the time-consuming of the printing process.

[0004] However, since a sealing edge will be generated during the process of the cast film being folded for the first time to form a loop, in order to ensure the flatness of the two surfaces of the packaging bag with patterns, usually there will be a fifth sealing edge structure at the middle position in the thickness direction of the finished product of the four-side sealed packaging bag. This sealing edge structure will affect the display of the internal product on the non-patterned surfaces on both sides of the packaging bag. Therefore, the existing production line of such four-side sealed packaging bags usually produces and processes the blown film produced by a blown film machine.

[0005] Therefore, this application proposes a production method and folding device for four-side sealed packaging bags using cast film. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems in the prior art, and a production method and folding device for packaging bags are proposed.

[0007] To achieve the above purpose, the present invention adopts the following technical solution: A packaging bag folding device includes a frame. A plurality of transmission rollers driven by a running motor fixedly arranged on the frame are rotatably connected to the frame. The frame is sequentially provided with a steering component and a folding component on the path of the transmission rollers for transmitting materials. Both the steering component and the folding component include a closing member for keeping the material passing between them in a gas-filled state. The folding component is used for forming a plurality of bending areas by squeezing the surfaces on both sides of the material before the material passes through the closing member of the folding component. The steering component is used for adjusting the included angle between the connection line of the two ends far away from each other after the material expands and the connection line of the two force application points squeezed by the folding component on the material, in the projection on the plane perpendicular to the path of the material passing through the folding component, before the material passes through the closing member of the steering component. The bending areas are arranged in a V-shaped structure at intervals along the width direction of the material. When the material with a plurality of bending areas passes through the closing member, the closing member can press out creases on the material along the bending areas.

[0008] The present invention is further configured such that: the steering assembly is connected to the frame through an adjustment frame, and a plurality of lead screws and slide rods passing through the adjustment frame are vertically arranged on the frame, and the lead screws are driven by a height adjustment motor fixedly arranged on the frame.

[0009] The present invention is further configured such that: the steering assembly includes a reference bracket fixedly connected to the adjustment frame and a deflection bracket rotatably connected to the adjustment frame. The deflection bracket is driven by a driving motor fixedly arranged on the adjustment frame. A reference roller is rotatably connected to the reference bracket, and a deflection roller is rotatably connected to the deflection bracket. The rotation angle of the driving motor is adjusted by a controller arranged on the frame. The material sequentially passes through the reference roller, the deflection roller, and the closing member included in the steering assembly.

[0010] The present invention is further configured such that: the closing member arranged in the steering assembly includes a contact roller rotatably connected to the deflection bracket and a first closing roller slid by a cylinder fixedly arranged on the deflection bracket to slide close to the contact roller. The material is attached to and bypasses the first closing roller.

[0011] The present invention is further configured such that: the folding assembly includes two side plates symmetrically arranged respectively and two groups of reducing rollers. The end faces of the side plates facing each other are parallel to the transmission direction of the material, and guiding strips capable of extruding the surface of the material are fixedly arranged on the surfaces. The two groups of reducing rollers are symmetrically arranged with respect to the guiding strips, and the distance therebetween gradually decreases along the transmission direction of the material.

[0012] The present invention is further configured such that: the side plates are slidably positioned on the frame, and both ends of each group of reducing rollers are slidably positioned on the frame.

[0013] The present invention is further configured such that: the closing member arranged in the folding assembly includes a second closing roller rotatably connected to the frame. The material is attached to and bypasses the second closing roller.

[0014] A method for producing a packaging bag, which uses the above-mentioned packaging bag folding device for folding, includes the following steps: S1: Guide the material with a sealing edge structure to sequentially pass through the steering assembly and the folding assembly, and then operate the steering assembly according to the positions of the old creases on both sides of the material to adjust the included angle between the projection of the line connecting the two ends that can be separated after the material expands and the line connecting the two force application points extruded on the material by the folding assembly on a plane perpendicular to the path of the material passing through the folding assembly; S2: Close the position of the closing member in the steering assembly close to the material, then inflate the material in the area between the two closing members before the material passes through the closing member in the folding assembly, and then close the position of the closing member in the folding assembly close to the material; S3: Adjust the folding assembly to squeeze both sides of the material, and then continue to guide the material until it leaves the folding device; S4: Start the running motor to let the transmission roller transport the material. New creases are formed on both sides of the material after passing through the steering assembly and the folding assembly. Then, the transmission roller guides the material to the next process or for winding; Among them, the material after inflation treatment presents a state of complete surface expansion and unfolding. Two groups of V-shaped structures with several connected cross-sections are formed between its two end faces. The edge-sealing structure on the material is at the new crease position closest to the end face.

[0015] In summary, the present invention has the following beneficial effects: Applying this folding device to the production line of four-edge-sealed packaging bags makes the four-edge-sealed packaging bags produced by processing the cast film produced by the cast film machine the same as those produced by the blown film. The production line is shorter, and the efficiency is higher due to the printing convenience of the cast film. Description of the Drawings

[0016] Figure 1 is the structural schematic of the present invention Figure 1 ; Figure 2 is the structural schematic of the present invention Figure 2 ; Figure 3 is the structural schematic diagram of the adjusting frame, sliding rod, screw rod and steering assembly of the present invention; Figure 4 is Figure 3 the enlarged view of part A in Figure 5 is the structural schematic diagram of the folding assembly of the present invention; Figure 6 is the structural schematic diagram of the side plate and guiding strip of the present invention.

[0017] In the figure: 1, frame; 2, steering assembly; 21, reference bracket; 22, deflection bracket; 23, drive motor; 24, reference roller; 25, deflection roller; 26, abutting roller; 27, first closing roller; 28, cylinder; 3, folding assembly; 31, side plate; 311, guiding strip; 32, shaping roller; 33, second closing roller; 4, adjusting frame; 41, sliding rod; 42, screw rod; 5, transmission roller. Detailed Embodiments

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0019] A packaging bag folding device, as Figure 1 and Figure 2 shown, includes a frame 1. Rotationally connected to the frame 1 are a number of transmission rollers 5 driven by a running motor fixedly arranged on the frame 1. On the path of the transmission rollers 5 for transporting materials, a turning component 2 and a folding component 3 are sequentially arranged on the frame 1. In this embodiment, the overall transport path of the materials is in an "n" - shaped structure when entering and leaving the folding device. The turning component 2 is arranged directly above the folding component 3, and the working distance between the two is not less than one meter. Both the turning component 2 and the folding component 3 include closures for keeping the materials passing between them in a gas - filled state. The materials are flat tubular films that have been heat - sealed and have a sealing structure formed on the outer surface. Gas can be filled into the materials by a gas gun. The criterion for sufficient gas filling is that the materials can expand and the surface is completely unfolded; Before entering the folding device, the flat tubular film is in the state of a cast film with one side of the surface printed, and two patterned areas are coated at intervals on its outer surface, and then the two ends of the cast film are heat - sealed to form it. The length of the patterned area is greater than the length of the non - patterned area. The flat tubular film will expand along the old creases into an oval - shaped cross - section due to the gas filled. At this time, the sealing structure is located near one of the long axes of the oval. Therefore, in order to make the sealing structure on one side of the patterned surface of the materials after the materials are refolded into a flat tubular film, acting as one of the sealing structures of a four - sealed packaging bag, the folding component 3 is used to form a number of bending areas by squeezing the two sides of the surface of the materials before the materials pass through its closure. The turning component 2 is used to adjust the included angle between the projection on the plane perpendicular to the path of the materials passing through the folding component 3 of the line connecting the two ends far away from each other after the materials expand and the line connecting the two force - applying points squeezed on the materials by the folding component 3 before the materials pass through its closure. Among them, the bending areas are in a V - shaped structure arranged at intervals along the width direction of the materials. When the materials with a number of bending areas pass through the closure, the closure can press creases on the materials along the bending areas.

[0020] As Figure 1 、 Figure 5 and Figure 6As shown, since there need to be two creases close to the patterned surface and at least one crease between these two creases between the patterned surfaces of the four-edge-sealed packaging bag, taking the production of a packaging bag with three creases between the patterned surfaces as an example, the folding assembly 3 includes two side plates 31 symmetrically arranged respectively and two groups of reducing rollers 32. The end faces of the side plates 31 facing each other are parallel to the conveying direction of the material, and guiding strips 311 capable of extruding the surface of the material are fixedly arranged on the surfaces. The two groups of reducing rollers 32 are symmetrically arranged with respect to the guiding strips 311, and the spacing gradually decreases along the conveying direction of the material. The two guiding strips 311 are arranged on both sides in the width direction of the material filled with gas, and are used to press the non-patterned surfaces of the material surface towards each other into the material. To ensure smooth contact between the material and the guiding strips 311, the end face contour of the guiding strips 311 in contact with the material is an arc line, that is, the guiding strips 311 can be gradually inserted into the material. The two groups of reducing rollers 32 and the two side plates 31 jointly surround the material, guiding the cross-section of the material filled with gas to approach a rectangular state, and enabling the guiding strips 311 to symmetrically and evenly increase the spacing between the middle bending area and the two side bending areas; Considering that the aspect ratios of different four-edge-sealed packaging bags are different, the side plates 31 are slidably positioned on the frame 1. Specifically, the side plates 31 can be moved in four directions in total on the horizontal plane through two handwheels. Both ends of each group of reducing rollers 32 are slidably positioned on the frame 1. Specifically, by adjusting the two ends of the reducing rollers 32 respectively, the included angle formed by the two groups of reducing rollers 32 and the minimum spacing in the horizontal direction can be changed.

[0021] As Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the steering assembly 2 is connected to the frame 1 through the adjusting frame 4. A plurality of lead screws 42 and slide rods 41 passing through the adjusting frame 4 are vertically arranged on the frame 1. The lead screws 42 are driven by a height-adjusting motor fixedly arranged on the frame 1. To facilitate the employees to pass the new flat tubular film through the steering assembly 2, the adjusting frame 4 can drive the steering assembly 2 to move down to a position close to the ground. Before inflation, the adjusting frame 4 can be adjusted to a position away from the folding assembly 3 and then inflated, so as to increase the process of the material expanding under the action of gas and make the surface of the film unfold more evenly; The steering assembly 2 includes a reference bracket 21 fixedly connected to the adjusting bracket 4, and a deflection bracket 22 rotatably connected to the adjusting bracket 4. The deflection bracket 22 is driven by a drive motor 23 fixedly arranged on the adjusting bracket 4. A reference roller 24 is rotatably connected to the reference bracket 21, and a deflection roller 25 is rotatably connected to the deflection bracket 22. In this embodiment, there is one reference roller 24 and two deflection rollers 25. The rotation angle of the drive motor 23 is adjusted by a controller arranged on the frame 1. The material passes through the reference roller 24, the deflection roller 25, and the closing member included in the steering assembly 2 in sequence. When the material is transported into the steering assembly 2, it will first pass through the reference roller 24. At this time, there is no difference when the flat tubular film passes through the transport roller 5 before passing through the steering assembly 2. Subsequently, when passing through the deflection roller 25 and the closing member in sequence, since the axes of the deflection roller 25 and the closing member are misaligned with the transport roller 5 due to the control of the drive motor 23, the major axis of the elliptical cross-section formed by the expanded material forms an angle with the projection of the line connecting the two guiding strips 311 on the ground, and the size of the angle is positively correlated with the length of the non-patterned surface of the film; Considering the convenience of guiding the material before the folding device is started, the closing member arranged in the steering assembly 2 includes a contact roller 26 rotatably connected to the deflection bracket 22, and a first closing roller 27 that is pushed by a cylinder 28 fixedly arranged on the deflection bracket 22 to slide close to the contact roller 26. The material is attached to and bypasses the first closing roller 27, and the closing member arranged in the folding assembly 3 includes a second closing roller 33 rotatably connected to the frame 1. The material is attached to and bypasses the second closing roller 33.

[0022] Beneficial effects: Applying this folding device to the production line of four-sealed edge packaging bags makes the style of the four-sealed edge packaging bags produced by processing the cast film produced by the cast film machine the same as that of the four-sealed edge packaging bags produced by the blown film. The production line is shorter, and the efficiency is higher due to the convenience of printing the cast film; Since there is no need to cut the sealing edge structure formed together when the cast film forms a flat tubular film in the production line, no secondary consumables are generated during film production, and there is no need to recycle waste materials.

[0023] A method for producing a packaging bag, which is folded by using the above-mentioned packaging bag folding device, includes the following steps: S1: Guide the material with a sealing edge structure to pass through the steering assembly 2 and the folding assembly 3 in sequence, and then operate the steering assembly 2 according to the positions of the old creases on both sides of the material to adjust the angle between the projection on the plane perpendicular to the path of the material passing through the folding assembly 3 of the line connecting the two ends that can be separated after the material expands and the line connecting the two force application points pressed on the material by the folding assembly 3; S2: Close the closure within the steering component 2 at its position close to the material. Subsequently, before the material passes through the closure in the folding component 3, inflate the material in the area between the two closures, and then let the closure in the folding component 3 close its position close to the material; S3: Adjust the folding component 3 so that the folding component 3 squeezes both sides of the material, and then continue to guide the material until the material leaves the folding device; S4: Start the running motor to let the conveying roller 5 convey the material. New creases are formed on both sides of the material after passing through the steering component 2 and the folding component 3. Subsequently, the conveying roller 5 guides the material to the next process or for winding; Among them, the material after inflation treatment presents a state where the surface is completely expanded and unfolded. Two groups of V-shaped structures with several connected cross-sections are formed between the two end faces of the material. The edge-sealing structure on the material is at the new crease position closest to the end face.

[0024] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed claims.

[0025] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A packaging bag folding device, comprising a frame (1), characterized in that: A plurality of conveying rollers (5) are rotatably connected to the frame (1) and driven by a running motor fixedly arranged on the frame (1). The frame (1) is sequentially provided with a steering assembly (2) and a folding assembly (3) on the path of the conveying rollers (5) for conveying materials. Both the steering assembly (2) and the folding assembly (3) include a closing member for keeping the materials passing between them in a gas-filled state. The folding assembly (3) is used for forming a plurality of bending zones by squeezing the surfaces on both sides of the materials before the materials pass through its closing member. The steering assembly (2) is used for adjusting the included angle between the projection on the plane perpendicular to the path of the materials passing through the folding assembly (3) of the line connecting the two ends away from each other after the materials expand and the line connecting the two force application points squeezed on the materials by the folding assembly (3) before the materials pass through its closing member. The bending zones are arranged in a V-shaped structure at intervals along the width direction of the materials. When the materials with a plurality of bending zones pass through the closing member, the closing member can press out creases on the materials along the bending zones.

2. The folding device for packaging bags according to claim 1, characterized in that: The steering assembly (2) is connected to the frame (1) through an adjusting frame (4). A plurality of lead screws (42) and slide bars (41) vertically arranged on the frame (1) pass through the adjusting frame (4). The lead screws (42) are driven by a height-adjusting motor fixedly arranged on the frame (1).

3. The folding device for packaging bags according to claim 2, wherein: The steering assembly (2) includes a reference bracket (21) fixedly connected to the adjusting frame (4), and a deflection bracket (22) rotatably connected to the adjusting frame (4). The deflection bracket (22) is driven by a driving motor (23) fixedly arranged on the adjusting frame (4). A reference roller (24) is rotatably connected to the reference bracket (21), and a deflection roller (25) is rotatably connected to the deflection bracket (22). The rotation angle of the driving motor (23) is adjusted by a controller arranged on the frame (1). The materials sequentially pass through the reference roller (24), the deflection roller (25), and the closing member included in the steering assembly (2).

4. A packaging bag folding device according to claim 3, characterized in that: The closing member arranged in the steering assembly (2) includes an abutting roller (26) rotatably connected to the deflection bracket (22), and a first closing roller (27) slid by a cylinder (28) fixedly arranged on the deflection bracket (22) to slide close to the abutting roller (26). The materials are attached to and bypass the first closing roller (27).

5. A packaging bag folding device according to claim 1, characterized in that: The folding assembly (3) includes two side plates (31) symmetrically arranged respectively and two groups of reducing rollers (32). The end faces of the side plates (31) facing each other are parallel to the conveying direction of the materials, and guiding strips (311) capable of squeezing the surfaces of the materials are fixedly arranged on the surfaces. The two groups of reducing rollers (32) are symmetrically arranged with respect to the guiding strips (311), and the spacing gradually decreases along the conveying direction of the materials.

6. The folding device for packaging bags according to claim 5, wherein: The closing member arranged in the folding assembly (3) includes a second closing roller (33) rotatably connected to the frame (1). The materials are attached to and bypass the second closing roller (33).

7. A packaging bag folding device according to claim 5, characterized in that: The side plates (31) are slidably positioned on the frame (1), and both ends of each group of reducing rollers (32) are slidably positioned on the frame (1).

8. A method for producing a packaging bag, characterized in that: Folding is performed using the packaging bag folding device according to any one of claims 1 to 7, including the following steps: S1: Guide the material with the edge-sealing structure to sequentially pass through the steering component (2) and the folding component (3). Subsequently, operate the steering component (2) according to the positions of the old creases on both sides of the material, and adjust the included angle between the line connecting the two ends that can be separated after the material expands and the line connecting the two force application points extruded on the material by the folding component (3) in the plane perpendicular to the path of the material passing through the folding component (3). S2: Close the closing member in the steering component (2) at the position close to the material. Subsequently, before the material passes through the closing member in the folding component (3), inflate the material in the area between the two closing members, and then close the closing member in the folding component (3) at the position close to the material. S3: Adjust the folding component (3) so that the folding component (3) extrudes both sides of the material, and then continue to guide the material until the material leaves the folding device. S4: Start the operating motor to make the transmission roller (5) transmit the material. New creases are formed on both sides of the material after passing through the steering component (2) and the folding component (3). Subsequently, the transmission roller (5) guides the material to the next process or winds it up. Wherein, the material after inflation treatment presents a state of being completely expanded and unfolded on the surface. Two groups of cross-sections with several connected V-shaped structures are formed between the two end faces of the material. The edge-sealing structure on the material is at the crease position close to one of the end faces.

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