Bottom-closing device for packaging bags and packaging bag production equipment

Abstract

This utility model discloses a bottom-closing device for packaging bags and packaging bag production equipment. The bottom-closing device includes a main shaft disposed on the downstream side of a conveying component, and a folding knife assembly and a pressing assembly disposed on one side of the main shaft. The folding knife assembly includes a mounting shaft eccentrically disposed on one side of the main shaft and a folding knife extending axially on the mounting shaft. The pressing assembly is sleeved on the main shaft and has a pressing portion extending circumferentially. The main shaft rotates so that the folding knife engages with the bottom-folding groove on the conveying component to bend the downstream end of the cylindrical substrate relative to the substrate body. Then, the pressing portion engages with the outer circumferential surface of the conveying component to clamp the substrate body of the cylindrical substrate. While the conveying component is conveying the cylindrical substrate, it flexibly clamps the substrate body to prevent the substrate body from being stretched and deformed. The other part of the substrate body with the bottom open is closed by other structures, reducing the number of waistlines on the upper side of the final packaged bag.

Description

Technical Field

[0001] This utility model relates to the field of packaging bag processing technology, and in particular to a bottom-closing device for packaging bags, which can be used in packaging bag production equipment. Background Technology

[0002] Packaging bags, as a common type of packaging container, are widely used in retail, food, and clothing industries. Their structure typically includes a pair of front panels, a pair of side panels, and a bottom. Based on the sealing method, packaging bags can be divided into bottom-sealed and side-sealed types. For bottom-sealed packaging bags, the production process generally involves first forming a cylindrical structure by surrounding the base material with a supporting component. Then, a bottom-closing device folds one end of the cylindrical structure, creating the bottom of the packaging bag.

[0003] In existing technologies, the bottom-closing device is often equipped with a pair of folding blades that squeeze one open end of the cylindrical structure to form indentations on the two side edges of the bottom surface. However, the bottom of the open cylindrical structure overlaps with the side of the cylindrical structure, resulting in two waistlines on the side of the final packaging bag. This not only affects the appearance of the packaging bag, but also makes the packaging bag prone to bending from the two waistlines when it is unfolded, reducing the stability of the packaging bag and making it difficult for users to put items into the bag. Utility Model Content

[0004] The purpose of this invention is to solve the technical problem that in the prior art, when the pair of folding blades of the bottom closing device are working on the bottom surface of the cylindrical substrate, the resulting packaging bag will have two waistlines on the side, which not only affects the appearance of the packaging bag, but also makes the packaging bag in the unfolded state prone to bending from the two waistlines, reducing the stability of the packaging bag.

[0005] To solve the above-mentioned technical problems, the present invention discloses a bottom-closing device for packaging bags. This bottom-closing device can be used in packaging bag production equipment, which includes a conveying component for transporting cylindrical substrates.

[0006] Specifically, the bottom-closing device provided in this embodiment includes a main shaft disposed downstream of the conveying component, and a folding blade assembly and a pressing assembly disposed on one side of the main shaft. The folding blade assembly includes a mounting shaft eccentrically disposed on one side of the main shaft and a folding blade disposed on the mounting shaft extending axially. The pressing assembly is sleeved on the main shaft and has a pressing portion extending circumferentially. The pressing portion and the folding blade are circumferentially offset from each other on the main shaft and are located downstream of the folding blade in the rotation direction of the main shaft.

[0007] The conveying component is provided with a folding groove. The main shaft rotates so that the folding knife cooperates with the folding groove to bend the downstream part of the cylindrical substrate relative to the substrate body. The pressing part cooperates with the outer peripheral surface of the conveying component to clamp the substrate body of the cylindrical substrate.

[0008] Using the above technical solution, the bottom-closing device provided in this embodiment only has a folding blade located on the mounting shaft, compared with the bottom-closing device in the prior art. This allows the pressing component to be integrated on the main shaft, making the bottom-closing device more compact and space-saving. When the conveying component transports the cylindrical substrate to the corresponding position of the bottom-closing device, the main shaft rotates, causing the folding blade on the mounting shaft to cooperate with the bottom-folding groove, bending the downstream end of the cylindrical substrate relative to the substrate body. For example, the folding blade is inserted into the bottom-folding groove, forming a crease in the substrate between the folding blade and the bottom-folding groove. Alternatively, the folding blade inserts the substrate corresponding to the bottom-folding groove into the bottom-folding groove. Furthermore, the pressing part of the pressing component will then cooperate with the outer peripheral surface of the conveying component, clamping the substrate body as the conveying component transports the cylindrical substrate. This prevents the substrate body from being stretched and deformed when the downstream end of the cylindrical substrate is bent due to the cooperation of the folding blade and the bottom-folding groove, improving the flatness of the substrate body during the bottom-closing process. Furthermore, the bent downstream end of the cylindrical substrate will cooperate with the downstream guide component, ultimately adhering to the outer surface of the substrate body.

[0009] The bottom-closing device provided in this embodiment can bend the downstream end portion of the cylindrical substrate, while the other part of the substrate body with the bottom open is closed by other structures. This reduces the number of waistlines on the side of the final packaging bag, improves the flatness of the side of the packaging bag, makes the packaging bag more stable in the unfolded state, and also increases the aesthetics of the packaging bag.

[0010] The present invention also discloses a bottom-closing device for a packaging bag, wherein the mounting shaft and the main shaft are arranged parallel to each other and connected together by a pair of radially extending first connecting arms. Each first connecting arm has one end fixedly connected to one end of the main shaft and the other end rotatably connected to a corresponding end of the mounting shaft, allowing the mounting shaft to rotate relative to the first connecting arm.

[0011] By adopting the above technical solution, when the folding blade of the bottom closing device is engaged with the bottom folding groove, the folding blade may be inserted into the bottom folding groove. As the main shaft rotates further, the folding blade may collide with the side wall of the bottom folding groove. The mounting shaft, through the rotation of the first connecting arm, ensures that the folding blade avoids the side wall of the bottom folding groove when it exits, thus protecting both the folding blade and the side wall of the bottom folding groove. At the same time, it can also prevent the portion of the substrate inserted into the bottom folding groove from being damaged by the folding blade when it exits, provided that the substrate is accurately inserted into the bottom folding groove.

[0012] This utility model also discloses a bottom-closing device for packaging bags. A pair of connecting flanges are provided on the frame of the packaging bag production equipment. Each connecting flange is sleeved on a corresponding end of the main shaft and located axially outside the first connecting arm. Furthermore, a rocker arm is provided between a corresponding end of the mounting shaft and a corresponding connecting flange. A circumferentially extending guide groove is formed on the end face of the connecting flange facing the mounting shaft. One end of the rocker arm is slidably disposed within the guide groove, and the other end is fixedly connected to the corresponding end of the mounting shaft. The rocker arm moves along the guide groove and can rotate the mounting shaft relative to the first connecting arm in conjunction with it.

[0013] Using the above technical solution, both ends of the main shaft are mounted on the frame of the packaging bag production equipment via connecting flanges. A guide groove on the connecting flange is slidably connected to one end of the swing arm. When the main shaft rotates, one end of the swing arm rotates along the guide groove. When the folding knife needs to retract from the folding groove, the swing arm swings under the guidance of the guide groove, causing the mounting shaft to rotate. The folding knife on the mounting shaft can then avoid the side wall of the folding groove. This design structure, which drives the mounting shaft to rotate, is simple and does not interfere with the rotation of the main shaft.

[0014] This utility model also discloses a bottom-closing device for a packaging bag. A guide groove extends circumferentially along the connecting flange. The outer circumferential sidewall of the guide groove extends in a closed circle along the circumferential direction of the connecting flange, while the inner circumferential sidewall has a cam shape with gradually changing radial dimensions around the rotation axis of the connecting flange. A stepped surface is formed between the portion of the cam shape with the largest radial dimension and the portion with the smallest radial dimension. Furthermore, when the folding blade and the bottom-closing groove are engaged, one end of the rocker arm is located at the position of maximum radial dimension on the inner circumferential sidewall of the guide groove.

[0015] Using the above technical solution, when the folding blade and the bottom groove are engaged, one end of the rocker arm is located at the point of maximum radial dimension on the inner circumferential sidewall of the guide groove. At this point, the width of the guide groove is at its minimum, for example, slightly larger than the outer diameter of one end of the rocker arm or exactly matching the diameter of one end of the rocker arm. The rocker arm is less prone to swaying, allowing the folding blade to accurately engage with the bottom groove. Only when one end of the rocker arm moves from the point of maximum to minimum radial dimension in the cam shape will it sway more noticeably, causing the mounting shaft and the folding blade to rotate and avoid the sidewall of the bottom groove. Furthermore, the outer circumferential sidewall of the guide groove extends in a closed circle along the circumference of the connecting flange, while the inner circumferential sidewall has a cam shape with gradually changing radial dimension around the rotation axis of the connecting flange. In other words, the width of the guide groove is gradually changing in other parts, allowing the rocker arm to rotate relatively smoothly with the main shaft in other parts.

[0016] This utility model also discloses a bottom-closing device for a packaging bag. The mounting shaft includes a shaft body and a clamping plate. The shaft body has a mounting groove adapted to a folding knife. The folding knife is assembled in the mounting groove and clamped by the clamping plate, with one end of the folding knife extending out of the mounting groove. Furthermore, multiple adjustment holes are formed on the folding knife, each extending in the direction of the folding knife extending out of the mounting groove. A fastener for the folding knife passes through the clamping plate and the corresponding adjustment hole on the folding knife and is fixedly connected to the shaft body.

[0017] By adopting the above technical solution, the mounting groove on the shaft body can ensure the accurate assembly of the folding knife. Furthermore, by adjusting the assembly position of the adjusting hole on the folding knife and the fastener of the folding knife, the length of the folding knife extending out of the mounting shaft can be changed to meet the folding requirements of different depth folding grooves or substrates with different hardness.

[0018] The present invention also discloses a bottom-closing device for a packaging bag. The pressing assembly includes a pressure roller, which has an inwardly recessed portion in the circumferential direction. The mounting shaft and the main shaft are both embedded in the recessed portion, and the outer wall surface of the pressure roller in the circumferential direction forms a pressing portion.

[0019] Using the above technical solution, the pressure roller is mounted on the mounting shaft and the main shaft through the recess, ensuring that the pressing part on the pressure roller can be circumferentially offset from the folding knife on the mounting shaft. Furthermore, this structure makes the pressure roller easy to assemble and disassemble.

[0020] The present invention also discloses a bottom-closing device for a packaging bag, wherein a pressure roller has a first wall surface and a second wall surface that are connected in the circumferential direction, the diameter of the first wall surface is larger than the diameter of the second wall surface, the part where the first wall surface and the second wall surface are connected forms a stepped surface, the first wall surface of the pressure roller constitutes a pressing part, and a recess is formed on the second wall surface.

[0021] Using the above technical solution, the pressure roller clamps the substrate body on the conveying component through the first wall, while the outer periphery of the second wall forms a clearance space to prevent interference with other components. The recess on the second wall will not affect the pressing part.

[0022] This utility model also discloses a bottom-closing device for a packaging bag. A second connecting arm is fixedly installed on the main shaft at a portion adjacent to the pressure roller. The end face of the second connecting arm near the pressure roller is in contact with the end face of the pressure roller. Furthermore, the second connecting arm and the pressure roller have connecting holes at corresponding positions. An axial fastener passes through the connecting holes of the second connecting arm and the pressure roller in sequence to fix the second connecting arm and the pressure roller axially on the main shaft.

[0023] By adopting the above technical solution, the assembly stability of the pressure roller and the main shaft is further improved by the second connecting arm. At the same time, the pressure roller is fixed together with the second connecting arm by the axial fastener, which plays a limiting role in the axial direction of the pressure roller on the main shaft, ensuring that the pressing part of the pressure roller can accurately clamp the corresponding part of the substrate body.

[0024] The present invention also discloses a packaging bag production equipment, including a bottom-closing device for any of the above-mentioned packaging bags, wherein the conveying component is configured as a hub, and a transmission component is provided between the hub and the main shaft, wherein the hub and the main shaft rotate in opposite directions.

[0025] By adopting the above technical solution, the hub of this packaging bag production equipment drives the main shaft to rotate in opposite directions through the transmission component, thereby bending the downstream part of the cylindrical substrate on the outer periphery of the hub, while the other part of the substrate body with the bottom opened is closed through other structures. This reduces the number of waistlines on the upper side of the final packaging bag, improves the flatness of the side of the packaging bag, makes the packaging bag more stable in the unfolded state, and also increases the aesthetics of the packaging bag.

[0026] The present invention also discloses a packaging bag production equipment, wherein a guide component is provided on the frame of the packaging bag production equipment on the downstream side of the bottom closing device.

[0027] The guide assembly includes a guide plate fixedly connected to the frame, which guides the portion of the cylindrical substrate that is bent by the folding blade and the folding groove.

[0028] By adopting the above technical solution, the guide plate guides the part of the cylindrical substrate that is bent by the folding knife and the folding groove on the bottom surface, so that the downstream part of the bent cylindrical substrate fits better against the outer surface of the substrate body.

[0029] The beneficial effects of this utility model are as follows:

[0030] This utility model discloses a bottom-closing device for packaging bags. The bottom-closing device includes a main shaft disposed downstream of a conveying component, and a folding blade assembly and a pressing assembly disposed on one side of the main shaft. The folding blade assembly includes a mounting shaft eccentrically disposed on one side of the main shaft and a folding blade extending axially on the mounting shaft. The pressing assembly is sleeved on the main shaft and has a pressing portion extending circumferentially. The pressing portion and the folding blade are circumferentially offset from the main shaft and are located downstream of the folding blade in the rotation direction of the main shaft. The conveying component of the packaging bag production equipment is provided with a bottom-folding groove. The main shaft rotates so that the folding blade cooperates with the bottom-folding groove to bend the downstream end of the cylindrical substrate relative to the substrate body. Then, the pressing portion cooperates with the outer circumferential surface of the conveying component to clamp the substrate body of the cylindrical substrate. While the conveying component is conveying the cylindrical substrate, it flexibly clamps the substrate body, preventing the substrate body from being stretched and deformed when the downstream end of the cylindrical substrate is bent due to the cooperation of the folding blade and the bottom-folding groove, thereby improving the flatness of the substrate body during the bottom-closing process. The bottom-closing device provided in this embodiment can bend the downstream end portion of the cylindrical substrate, while the other part of the substrate body with the bottom open is closed by other structures. This reduces the number of waistlines on the upper side of the final packaging bag, improves the flatness of the packaging bag's side, allows the packaging bag to be in a more stable unfolded state, and also increases the packaging bag's aesthetics. Attached Figure Description

[0031] Figure 1 A schematic diagram of the assembly structure of the bottom-closing device of the packaging bag provided in this embodiment of the utility model, mounted on the packaging bag production equipment.

[0032] Figure 2 This is a schematic diagram of the bottom-closing device provided in an embodiment of the present utility model;

[0033] Figure 3 This is a schematic diagram of the cylindrical substrate structure;

[0034] Figure 4 A schematic diagram of the connecting flange used for assembling the spindle;

[0035] Figure 5 An exploded structural diagram of the mounting shaft and folding knife in the bottom-closing device provided in an embodiment of this utility model;

[0036] Figure 6 A schematic diagram of the pressure roller in the bottom-closing device provided in this embodiment of the utility model.

[0037] Explanation of reference numerals in the attached figures:

[0038] 10. Conveying components; 110. Wheel hub; 101. Folded bottom groove;

[0039] 20. Bottom-closing device;

[0040] 210. Spindle;

[0041] 220. Folding knife assembly; 221. Mounting shaft; 2210. Shaft body; 2211. Pressure plate;

[0042] 222. Folding knife; 2221. Adjustment hole; 223. First connecting arm; 224. Swing rod;

[0043] 230, pressing assembly; 231, pressing part; 2310, pressure roller; 2311, recess; 2312, first wall surface; 2313, second wall surface; 2314, weight reduction hole; 232, second connecting arm;

[0044] 30. Connecting flange; 310. Guide groove; 311. Outer peripheral sidewall; 312. Inner peripheral sidewall;

[0045] 40. Guide assembly; 410. Guide plate;

[0046] 1. Main body of the substrate; 2. Bending part; 3. Crease; Detailed Implementation

[0047] As mentioned in the background section, when the pair of folding blades of the existing bottom-closing device work on the bottom surface of the cylindrical substrate, the resulting packaging bag will have two waistlines on the side. This not only affects the aesthetics of the packaging bag, but also makes the packaging bag in the unfolded state prone to bending from the two waistlines, reducing the stability of the packaging bag.

[0048] This utility model provides a bottom-closing device for packaging bags. This device has only one folding blade assembly on its main shaft, and a pressing assembly integrated onto the main shaft. Specifically, the folding blade assembly includes a mounting shaft eccentrically positioned on one side of the main shaft and a folding blade extending axially on the mounting shaft. The pressing assembly is sleeved on the main shaft and has a pressing portion extending circumferentially. When the conveying component transports the cylindrical substrate to the corresponding position of the bottom-closing device, the main shaft rotates, causing the folding blade on the mounting shaft to engage with the folding groove, bending the downstream end of the cylindrical substrate relative to the substrate body. The pressing portion of the pressing assembly then immediately engages with the outer circumferential surface of the conveying component. This process is repeated as the conveying component transports the cylindrical substrate. The substrate body is held in a responsive manner, preventing the substrate body from being stretched and deformed when the downstream end of the cylindrical substrate is bent due to the interaction between the folding blade and the bottom folding groove. Furthermore, the bent downstream end of the cylindrical substrate will cooperate with the downstream guide component and finally adhere to the outer surface of the substrate body. The other part of the substrate body with the bottom open is closed by other structures. It should be noted that other structures should be closure methods that do not require the substrate to be inserted into the bottom folding groove, thereby reducing the number of waistlines on the upper side of the packaging bag in the final production, improving the flatness of the side of the packaging bag, making the packaging bag more stable in the unfolded state, and also increasing the aesthetics of the packaging bag.

[0049] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0050] like Figure 1 As shown, the bottom-closing device of the packaging bag provided in this embodiment is installed on the packaging bag production equipment. Generally, the packaging bag production equipment includes a frame and a conveying component 10 that transports the cylindrical substrate by rotating a hub structure or by a conveyor belt. Taking the conveying component 10 as a hub 110 as an example, the conveying component 10 is provided with a bottom-opening device upstream of the bottom-closing device. The bottom-opening device opens one end (e.g., the downstream end) of the cylindrical substrate to facilitate subsequent closing. Furthermore, an adhesive applicator is provided between the downstream of the bottom-opening device and the upstream of the bottom-closing device. The adhesive applicator can apply adhesive to the opened bottom of the cylindrical substrate, so that the bottom of the substrate can be directly or partially sealed when the bottom-closing device closes. Regarding the bottom-opening device, the adhesive applicator, and other structures on the packaging bag production equipment, those skilled in the art can design them according to actual conditions and specific needs. This embodiment does not specifically limit them.

[0051] like Figure 2 As shown, the bottom-closing device 20 provided in this embodiment includes a main shaft 210 disposed downstream of the conveying component 10, and a folding blade assembly 220 and a pressing assembly 230 disposed on one side of the main shaft 210. The folding blade assembly 220 includes a mounting shaft 221 eccentrically disposed on one side of the main shaft 210 and a folding blade 222 axially extending on the mounting shaft 221. The pressing assembly 230 is sleeved on the main shaft 210 and has a pressing portion 231 extending circumferentially. The pressing portion 231 and the folding blade 222 are circumferentially offset from the main shaft 210, and the pressing portion 231 is located downstream of the folding blade 222 in the rotation direction of the main shaft 210. Therefore, the bottom-closing device 20 provided in this embodiment only has one folding blade 222 located on the mounting shaft 221 compared to the bottom-closing devices in the prior art, so that the pressing assembly 230 can be integrated on the main shaft 210, making the structure of the bottom-closing device 20 more compact and occupying less space.

[0052] When the conveying component 10 conveys the cylindrical substrate to the corresponding position of the bottom-closing device 20, the main shaft 210 rotates, causing the folding blade 222 on the mounting shaft 221 to engage with the bottom-folding groove 101 on the hub 110, bending the downstream end of the cylindrical substrate relative to the substrate body. For example, the folding blade 222 is inserted into the bottom-folding groove 101, creating a crease in the substrate portion between the folding blade 222 and the bottom-folding groove 101. Alternatively, the folding blade 222 inserts the substrate portion corresponding to the bottom-folding groove 101 into the bottom-folding groove 101, and... Furthermore, the pressing part 231 of the pressing assembly 230 will immediately cooperate with the outer peripheral surface of the conveying component 10, and clamp the substrate body in turn while the conveying component 10 is conveying the cylindrical substrate. This prevents the substrate body from being stretched and deformed when the downstream end of the cylindrical substrate is bent due to the cooperation between the folding blade 222 and the folding groove 101, thereby improving the flatness of the substrate body during the bottom closing process. In addition, the bent downstream end of the cylindrical substrate will cooperate with the downstream guide structure and finally adhere to the outer surface of the substrate body.

[0053] Furthermore, to facilitate understanding of the working process of the bottom-closing device 20, the following will be combined with... Figure 3 The structure of the cylindrical substrate is described, wherein the cylindrical substrate, before being processed by the bottom-closing device 20, is as follows: Figure 3 The left end forms the opening of the packaging bag, and a handle is pre-attached to the left end of the cylindrical substrate. Figure 3 Crease 3 in the middle is formed by the cooperation of folding blade 222 and folding groove 101, and the cylindrical substrate is in Figure 3 The right end is a bent portion 2, which bends toward the substrate body 1 on the left. The pressing part 231 of the pressing assembly 230 and the outer periphery of the conveying component 10 clamp the substrate body 1 to prevent the substrate body 1 from being pulled and deformed. It should be noted that the bottom part stacked on the substrate body 1 is closed by other components.

[0054] The bottom-closing device 20 provided in this embodiment can bend the downstream end portion of the cylindrical substrate, while the other part of the substrate body with the bottom open is closed by other structures. This reduces the number of waistlines on the side of the final packaging bag, improves the flatness of the side of the packaging bag, makes the packaging bag more stable in the unfolded state, and also increases the aesthetics of the packaging bag.

[0055] The specific structure of spindle 210 is described below.

[0056] like Figure 2As shown, the main shaft 210, as the main support structure of the bottom-closing device 20, is typically mounted on the frame. In this embodiment, a pair of connecting flanges 30 are provided on the frame at corresponding positions at both ends of the main shaft 210. Each connecting flange 30 is sleeved on a corresponding end of the main shaft 210, and at least one end of the main shaft 210 extends out of the corresponding connecting flange 30 and is connected to the drive structure for transmission. For example, in one embodiment, one end of the main shaft 210 is connected to the output end of the drive motor via a coupling. Alternatively, in another embodiment, when the conveying component 10 of the packaging bag production equipment is configured as a hub 110, the hub 110 is connected to the drive structure for transmission, and the hub 110 is connected to one end of the main shaft 210 via a gear set for transmission. The drive structure drives the hub 110 to rotate to sequentially convey the cylindrical substrate, while the hub 110 drives the main shaft 210 to rotate in opposite directions via the gear set.

[0057] Of course, the assembly structure between the spindle 210 and the frame is not limited to the connecting flange 30 in the above embodiment. A pair of assembly holes can also be opened on the frame, and the two ends of the spindle 210 can be respectively assembled in the corresponding assembly holes. This embodiment does not limit this to a single one.

[0058] The specific structure of the folding knife assembly 220 is described below.

[0059] In this embodiment, as Figure 2 As shown, the folding knife assembly 220 includes a mounting shaft 221 and a folding knife 222 mounted on the mounting shaft 221. The mounting shaft 221 is arranged parallel to the main shaft 210 and is connected to it by a pair of radially extending first connecting arms 223. Each first connecting arm 223 has one end fixedly connected to one end of the main shaft 210 and the other end rotatably connected to the corresponding end of the mounting shaft 221.

[0060] When the folding blade 222 of the folding blade assembly 220 engages with the folding bottom groove 101, the folding blade 222 may be inserted into the folding bottom groove 101. As the main shaft 210 rotates further, the folding blade 222 may collide with the side wall of the folding bottom groove 101. Therefore, the mounting shaft 221 can rotate relative to the first connecting arm 223, so that the folding blade 222 avoids the side wall of the folding bottom groove 101 when it exits, thereby protecting both the folding blade 222 and the side wall of the folding bottom groove 101. At the same time, it can also prevent the portion of the substrate inserted into the folding bottom groove 101 from being damaged by the folding blade 222 when it exits, provided that the substrate is accurately inserted into the folding bottom groove 101.

[0061] To ensure accurate engagement between the folding blade 222 and the folding groove 101, and to allow the folding blade 222 to rotate as expected and avoid the sidewall of the folding groove 101 when the main shaft 210 rotates further and exits the folding groove 101, a rocker arm 224 is provided between one end of the mounting shaft 221 and a corresponding connecting flange 30. A circumferentially extending guide groove 310 is formed on the end face of the connecting flange 30 facing the mounting shaft 221. One end of the rocker arm 224 is slidably disposed within the guide groove 310, and the other end is fixedly connected to the corresponding end of the mounting shaft 221. The rocker arm 224 moves along the guide groove 310 and can rotate the mounting shaft 221 relative to the first connecting arm 223 in conjunction with it. It should be noted that the rocker arm 224 can be provided between one end of the mounting shaft 221 and a corresponding connecting flange 30, or it can be provided between both ends of the mounting shaft 221 and their respective corresponding connecting flanges 30. This embodiment does not limit this to a single specific configuration.

[0062] When the main shaft 210 rotates, one end of the rocker arm 224 rotates along the guide groove 310. When the folding knife 222 needs to exit from the folding bottom groove 101, the rocker arm 224 swings under the guidance of the guide groove 310, thereby causing the mounting shaft 221 to rotate. The folding knife 222 on the mounting shaft 221 can avoid the side wall of the folding bottom groove 101. This design structure that drives the mounting shaft 221 to rotate is simple and does not interfere with the rotation of the main shaft 210.

[0063] Specifically, such as Figure 4 As shown, the guide groove 310 extends circumferentially along the connecting flange 30, and the outer peripheral sidewall 311 of the guide groove 310 extends in a closed circle along the circumferential direction of the connecting flange 30. The inner peripheral sidewall 312 of the guide groove 310 has a cam shape with a gradually changing radial dimension around the axis of rotation of the connecting flange 30, wherein a stepped surface is formed between the part with the largest radial dimension and the part with the smallest radial dimension in the cam shape. Furthermore, when the folding blade 222 is engaged with the folding bottom groove 101, one end of the rocker arm 224 is located at the part with the largest radial dimension of the inner peripheral sidewall 312 in the guide groove 310.

[0064] With the folding blade 222 engaged with the folding bottom groove 101, one end of the rocker arm 224 is located at the point of maximum radial dimension of the inner circumferential sidewall 312 in the guide groove 310. At this time, the width of the guide groove 310 is at its minimum, for example, slightly larger than the outer diameter of one end of the rocker arm 224 or exactly matched with the diameter of one end of the rocker arm 224. The rocker arm 224 is not prone to swaying, ensuring that the folding blade 222 can accurately engage with the folding bottom groove 101. When one end of the rocker arm 224 moves from the point of maximum radial dimension to the point of minimum radial dimension in the cam shape, one end of the rocker arm 224 will sway more significantly, thereby causing the mounting shaft 221 and the folding blade 222 to rotate and avoid the sidewall of the folding bottom groove 101. Furthermore, the outer peripheral sidewall 311 of the guide groove 310 extends in a closed circle along the circumference of the connecting flange 30, while the inner peripheral sidewall 312 has a cam shape with gradually changing radial dimensions around the axis of rotation of the connecting flange 30. In other words, the width of the guide groove 310 is gradually changing in other parts, and the rocker arm 224 can rotate relatively smoothly with the main shaft 210 in other parts.

[0065] Therefore, the extending directions of the outer peripheral sidewall 311 and the inner peripheral sidewall 312 of the guide groove 310 affect the way the folding blade 222 on the mounting shaft 221 exits from the folding groove 101, for example, in Figure 2 In the middle, the hub 110 and the main shaft 210 will rotate towards each other. The main shaft 210 rotates counterclockwise so that the folding knife 222 is inserted into the folding knife 222 slot. When the main shaft 210 rotates further, the rocker arm 224 swings clockwise under the guidance of the guide groove 310 and drives the mounting shaft 221 to rotate clockwise, so that the folding knife 222 on the mounting shaft 221 can avoid the lower side wall of the folding bottom groove 101.

[0066] Of course, the structure for guiding the rotation of the mounting shaft 221 is not limited to the structure of the rocker arm 224 and guide groove 310 in the above embodiment. It can also involve rotatably connecting the mounting shaft 221 to one end of the first connecting arm 223, and providing a torsion spring at the end of the mounting shaft 221. When the folding blade 222 on the mounting shaft 221 is inserted into the folding groove 101, the softness of the substrate is insufficient to overcome the elastic force of the torsion spring on the mounting shaft 221. When the folding blade 222 on the mounting shaft 221 exits the folding groove 101, it contacts the side wall of the folding groove 101. Under the pressure of the side wall of the folding groove 101, the mounting shaft 221 overcomes the elastic force of the torsion spring and rotates, thus exiting the folding groove 101. This embodiment does not limit the structure for causing the mounting shaft 221 to rotate; those skilled in the art can design it according to actual conditions and specific needs.

[0067] Furthermore, in this embodiment, as Figure 5As shown, the mounting shaft 221 includes a shaft body 2210 and a clamping plate 2211. The shaft body 2210 has a mounting groove adapted to the folding knife 222. The folding knife 222 is assembled in the mounting groove and clamped by the clamping plate 2211, with one end of the folding knife 222 extending out of the mounting groove. Furthermore, a plurality of adjustment holes 2221 are formed on the folding knife 222, each adjustment hole 2221 extending in the direction in which the folding knife 222 extends out of the mounting groove. Fasteners for the folding knife 222 pass through the clamping plate 2211 and the corresponding adjustment hole 2221 on the folding knife 222 and are fixedly connected to the shaft body 2210.

[0068] The mounting groove on the shaft body 2210 ensures the accurate assembly of the folding knife 222. Furthermore, by adjusting the assembly position of the adjusting hole 2221 on the folding knife 222 and the fastener of the folding knife 222, the length of the folding knife 222 extending out of the mounting shaft 221 can be changed to meet the folding requirements of different depth folding grooves 101 or substrates with different hardness.

[0069] Regarding the method of mounting the mounting shaft 221 with the folding knife 222, it is not limited to the structure in the above embodiment. Alternatively, a rectangular hole adapted to the folding knife 222 can be provided on the mounting shaft 221, and the folding knife 222 can be inserted into the rectangular hole and engaged by a retaining ring. Or, a rectangular groove can be provided on the mounting shaft 221, and the folding knife 222 can be embedded in the rectangular groove. Those skilled in the art can design according to actual conditions and specific needs. This embodiment does not limit this to a single method.

[0070] The specific structure of the pressing assembly 230 is described below.

[0071] In this embodiment, as Figure 2 and Figure 6 As shown, when the hub 110 and the main shaft 210 rotate towards each other, the pressure roller 2310 assembly, through the pressing part 231, engages with the outer peripheral surface of the hub 110 to press the substrate body in the middle. This prevents the substrate body from being stretched and deformed when the downstream end of the cylindrical substrate bends due to the engagement of the folding blade 222 and the folding groove 101. In contrast, the existing technology only uses the folding blade 222 to form an indentation on the substrate, which avoids this problem since the substrate does not bend. The pressing assembly 230 includes structures such as the pressure roller 2310, pressure plate, or pressure rod that can compress the substrate body.

[0072] Specifically, in this embodiment, the pressing assembly 230 includes two pressing rollers 2310 spaced apart along the axial direction of the main shaft 210. Each pressing roller 2310 has an inwardly recessed portion 2311 in the circumferential direction. The mounting shaft 221 and the main shaft 210 are both embedded in the recessed portion 2311. The outer wall surface of the pressing roller 2310 in the circumferential direction forms a pressing portion 231.

[0073] like Figure 6As shown, the pressure roller 2310 is mounted on the mounting shaft 221 and the main shaft 210 through the recess 2311, ensuring that the pressing part 231 on the pressure roller 2310 can be circumferentially offset from the folding knife 222 on the mounting shaft 221. Furthermore, the pressure roller 2310 with this structure is easy to assemble and disassemble.

[0074] The structure of the pressure roller 2310 is described below using a single pressure roller 2310 as an example. The pressure roller 2310 has a first wall surface 2312 and a second wall surface 2313 connected circumferentially. The diameter of the first wall surface 2312 is larger than the diameter of the second wall surface 2313. The portion where the first wall surface 2312 and the second wall surface 2313 connect forms a stepped surface. The first wall surface 2312 of the pressure roller 2310 constitutes a pressing portion 231, and a recess 2311 is formed on the second wall surface 2313. Furthermore, to reduce the load on the driving components, an arc-shaped weight-reducing hole 2314 can be provided inside the first wall surface 2312 of the pressure roller 2310.

[0075] The pressure roller 2310 clamps the substrate body on the conveying component 10 through the first wall surface 2312, while the outer periphery of the second wall surface 2313 forms a clearance space to prevent interference with other components. The recess 2311 provided on the second wall surface 2313 will not affect the pressing part 231.

[0076] Furthermore, such as Figure 2 As shown, in this embodiment, a second connecting arm 232 is fixedly provided on the portion of the main shaft 210 adjacent to the pressure roller 2310. The end face of the second connecting arm 232 near the pressure roller 2310 is in contact with the end face of the pressure roller 2310. Furthermore, the second connecting arm 232 and the pressure roller 2310 have connecting holes formed at corresponding positions. An axial fastener passes through the connecting holes of the second connecting arm 232 and the pressure roller 2310 in sequence to fix the second connecting arm 232 and the pressure roller 2310 axially on the main shaft 210.

[0077] Specifically, the second connecting arm 232 further improves the assembly stability of the pressure roller 2310 and the main shaft 210. At the same time, the pressure roller 2310 is fixed together with the second connecting arm 232 by axial fasteners, which limit the pressure roller 2310 in the axial direction of the main shaft 210, ensuring that the pressing part 231 of the pressure roller 2310 can accurately clamp the corresponding part of the substrate body.

[0078] Of course, the structure of the pressing assembly 230 is not limited to the pressing roller 2310 in the embodiment. The pressing assembly 230 can also be set as a pressing rod arranged in an arc around the outer periphery of the main shaft 210. The pressing rod is connected to the outer periphery of the main shaft 210 through a connecting rod extending radially along the main shaft 210, so that the substrate body on the outer periphery of the hub 110 is clamped when the main shaft 210 rotates. This embodiment does not limit this to a single one.

[0079] This embodiment also provides a packaging bag production equipment, including the bottom-closing device 20 of the packaging bag provided in the above embodiment.

[0080] Furthermore, such as Figure 1 As shown, a guide assembly 40 is also provided on the frame of the packaging bag production equipment, located downstream of the bottom closing device 20.

[0081] Among them, such as Figure 2 As shown, the guide assembly 40 includes a guide plate 410 fixedly connected to the frame. The guide plate 410 guides the portion of the cylindrical substrate that is bent by the folding blade 222 and the folding groove 101.

[0082] In this embodiment, the guide plate 410 guides the portion of the cylindrical substrate that is bent by the folding blade 222 and the folding groove 101 on the bottom surface of the cylindrical substrate, so that the bent downstream end portion of the cylindrical substrate fits better against the outer surface of the substrate body.

[0083] Of course, the specific structure of the guide component 40 is not limited to the guide plate 410 in the above embodiment. In another alternative embodiment, the guide component 40 can also be a guide rod structure. This embodiment does not limit it to this only.

[0084] It should be noted that, in addition to the specific embodiments described above, those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model is presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to that embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. In order to provide a deep understanding of this utility model, many specific details are included in the above description, and this utility model may also be implemented without using these details. In addition, in order to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0085] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0086] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model.

[0087] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0088] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0089] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A bottom closing apparatus for a packaging bag, a packaging bag production apparatus including a conveying member that conveys a tubular base material, characterized by, The bottom-closing device includes a main shaft disposed downstream of the conveying component, and a folding blade assembly and a pressing assembly disposed on one side of the main shaft; wherein, The folding knife assembly includes a mounting shaft eccentrically disposed on one side of the main shaft, a folding knife extending axially on the mounting shaft, and a pressing assembly sleeved on the main shaft and having a pressing portion extending circumferentially. The pressing portion and the folding knife are circumferentially offset from the main shaft and located downstream of the folding knife in the rotation direction of the main shaft. The conveying component is provided with a folding groove. The main shaft rotates so that the folding knife cooperates with the folding groove to bend the downstream end of the cylindrical substrate relative to the substrate body. The pressing part cooperates with the outer peripheral surface of the conveying component to clamp the substrate body of the cylindrical substrate.

2. The closure for a bag as defined in claim 1, wherein The mounting shaft and the main shaft are arranged parallel to each other and connected together by a pair of radially extending first connecting arms; wherein one end of each first connecting arm is fixedly connected to one end of the main shaft and the other end is rotatably connected to the corresponding end of the mounting shaft, and the mounting shaft is rotatable relative to the first connecting arm.

3. The closure for a bag according to claim 2, wherein The packaging bag production equipment has a pair of connecting flanges on its frame. Each connecting flange is fitted onto a corresponding end of the main shaft and is located axially outside the first connecting arm. A rocker arm is provided between a corresponding end of the mounting shaft and a corresponding connecting flange. A guide groove extending circumferentially is formed on the end face of the connecting flange facing the mounting shaft. One end of the rocker arm is slidably disposed in the guide groove, and the other end is fixedly connected to the corresponding end of the mounting shaft. The rocker arm moves along the guide groove and can rotate the mounting shaft relative to the first connecting arm.

4. The closure for a bag according to claim 3, wherein The guide groove extends circumferentially along the connecting flange, the outer peripheral sidewall extends in a closed circle circumferentially along the connecting flange, and the inner peripheral sidewall has a cam shape with gradually changing radial dimensions around the axis of rotation of the connecting flange. A stepped surface is formed between the portion of the cam shape with the largest radial dimension and the portion with the smallest radial dimension. With the folding knife engaged with the folding groove, one end of the swing arm is located at the point of maximum radial dimension of the inner circumferential sidewall in the guide groove.

5. The closure for a bag according to claim 1, wherein The mounting shaft includes a shaft body and a clamping plate. The shaft body has a mounting groove adapted to the folding knife. The folding knife is fitted into the mounting groove and clamped by the clamping plate, with one end of the folding knife extending out of the mounting groove. Multiple adjustment holes are formed on the folding blade, and each adjustment hole extends along the direction in which the folding blade extends out of the mounting groove. The folding blade fastener passes through the clamping plate and the corresponding adjustment hole on the folding blade and is fixedly connected to the shaft body.

6. A closure for a bag as claimed in any one of claims 1 to 5, wherein, The pressing assembly includes a pressure roller with an inwardly recessed portion in its circumferential direction. The mounting shaft and the main shaft are both embedded in the recessed portion, and a portion of the outer wall surface of the pressure roller in the circumferential direction constitutes the pressing portion.

7. The closure for a bag according to claim 6, wherein The pressure roller has a first wall and a second wall that are in contact along its circumference. The diameter of the first wall is larger than the diameter of the second wall. The part where the first wall and the second wall are in contact forms a stepped surface. The first wall of the pressure roller constitutes the pressing part, and the second wall forms the recess.

8. The closure for a bag according to claim 6, wherein A second connecting arm is fixedly mounted on the main shaft at a portion adjacent to the pressure roller, and the end face of the second connecting arm near the pressure roller is partially abutted against the end face of the pressure roller; and, The second connecting arm and the pressure roller have connecting holes at corresponding positions. An axial fastener passes through the connecting holes of the second connecting arm and the pressure roller in sequence to fix the second connecting arm and the pressure roller axially on the main shaft.

9. A packaging bag production apparatus characterized by comprising: The device includes a bottom-closing device for a packaging bag as described in any one of claims 1 to 8, wherein the conveying component is configured as a hub, a transmission assembly is provided between the hub and the main shaft, and the hub rotates in conjunction with the main shaft in opposite directions.

10. The packaging bag production equipment as described in claim 9, characterized in that, On the frame of the packaging bag production equipment, a guide assembly is also provided downstream of the bottom-closing device; wherein... The guiding assembly includes a guide plate fixedly connected to the frame, which guides the portion of the bottom surface of the cylindrical substrate that is bent by the folding blade and the folding groove.

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