Film folding and tracking cutter mechanism

Abstract

The utility model provides a kind of film edge folding tracking cutter mechanism, including tool holder and swing assembly, the tool holder is equipped with the guide edge for hooking film cylinder material edge folding, the swing assembly includes swing seat and at least two swing arms, one end of the swing arm is hingedly arranged, the other end is connected with swing seat, the tool holder is fixed on the other side of swing seat, when film cylinder material width fluctuation, the guide edge is under the transverse thrust of film edge folding, swing seat is driven to realize self-adapting translation by the swing of swing arm, so that guide edge keeps hooking film cylinder material edge folding.The utility model discloses a kind of film edge folding tracking cutter mechanism, realizes the mechanical self-adapting tracking and accurate cutting of film edge folding, significantly improves product quality.

Description

Technical Field

[0001] This utility model relates to the field of plastic bag manufacturing technology, and more specifically, to a film folding tracking cutter mechanism. Background Technology

[0002] Film tubular material refers to a double-layered flat material formed by blow molding and flattening of plastic film. In the production process of plastic film bags, the folded edges of this tubular film usually need to be longitudinally cut to open it, so that the tubular material can be unfolded into a single film or made into a bag opening structure.

[0003] Currently, the industry commonly uses fixed-type cutting mechanisms for film folding and cutting. This fixed structure rigidly mounts the cutter assembly to the frame, and the relative position of the cutter and the guide edge is not adjustable. However, in actual production, due to factors such as film tension fluctuations, winding speed changes, temperature differences, and uneven material properties, the width of the film bobbin fluctuates in real time, causing the horizontal position of the folded edge to continuously shift. This leads to the following technical problems: when the folded edge deviates from the guide edge of the cutter, the cutter cannot align with the center of the folded edge, resulting in a cut with barbs or no cut at all, producing a large number of defective products; furthermore, the guide edge may scratch the film body after detaching from the folded edge, or form irregular cuts on the outside of the folded edge, resulting in low production quality. Utility Model Content

[0004] The purpose of this invention is to provide a film folding tracking and cutting mechanism, which realizes mechanical adaptive tracking and precise cutting of film folding, and significantly improves product quality.

[0005] The technical solution adopted by the film folding tracking cutter mechanism disclosed in this utility model is: A film folding tracking cutter mechanism includes a cutter holder and a swing assembly. The cutter holder has a guide edge for hooking the folding edge of the film tube. The swing assembly includes a swing base and at least two swing arms. One end of each swing arm is hinged and the other end is connected to the swing base. The cutter holder is fixed to the other side of the swing base. When the width of the film tube fluctuates, the guide edge, under the lateral thrust of the film folding edge, drives the swing base to achieve adaptive translation through the swing of the swing arms, so that the guide edge keeps hooking the folding edge of the film tube.

[0006] As a preferred embodiment, the swing arm includes a first swing arm and a second swing arm, the first swing arm and the second swing arm are arranged in parallel, and the first swing arm and the second swing arm are respectively connected to the swing seat to form a parallelogram mechanism.

[0007] As a preferred embodiment, the film folding tracking cutter mechanism further includes a sliding seat. Both the sliding seat and the swing seat are equipped with rolling bearings. One end of the first swing arm and the second swing arm are rotatably connected to the sliding seat via a first rotating shaft and a second rotating shaft, respectively. The first rotating shaft and the second rotating shaft are rotatably engaged with the sliding seat via the rolling bearings. The other end of the first swing arm and the second swing arm are rotatably connected to the swing seat via a third rotating shaft and a fourth rotating shaft, respectively. The third rotating shaft and the fourth rotating shaft are rotatably engaged with the swing seat via the rolling bearings.

[0008] As a preferred embodiment, when the width of the film tube fluctuates, the first swing arm and the second swing arm swing synchronously around the axes of the first, second, third, and fourth rotating shafts, causing the swing seat to move horizontally while maintaining its direction.

[0009] As a preferred embodiment, the film folding tracking cutter mechanism further includes a horizontal adjustment component, which includes a fixed plate and a guide rod. The two ends of the guide rod are connected to the fixed plate, and the sliding seat is slidably disposed on the guide rod, so that the entire cutter mechanism can slide along the guide rod to adapt to film tubes of different widths.

[0010] As a preferred embodiment, a first locking member is provided on one side of the sliding seat. The first locking member passes through the sliding seat and cooperates with the guide rod to lock the sliding seat onto the guide rod.

[0011] As a preferred embodiment, the film folding tracking cutter mechanism further includes a counterweight assembly, which includes a counterweight block and a support rod. The second rotating shaft extends out of the sliding seat and is connected to the support rod. The counterweight block is slidably mounted on the support rod to provide a force for the guide edge to tighten the film folding edge.

[0012] As a preferred embodiment, the support rod is provided with a second locking element for fixing the support rod to the second rotating shaft.

[0013] As a preferred embodiment, a hot knife assembly is installed on the knife holder. The hot knife assembly includes a heating unit, a clamping block, a hot cutting knife, and a movable block. The cutting edge of the hot cutting knife is correspondingly arranged with the cutting opening on the guide edge of the knife holder. The movable block is fixedly connected to the clamping block and is assembled on the swing seat through an adjustable connection structure.

[0014] As a preferred embodiment, the top of the guide edge is provided with an arc surface, and a cutting opening is provided on the guide edge. The inner surface of the cutting opening is an inclined surface or an arc surface, which is used to guide the cutting edge of the hot cutting knife and accommodate the cutting edge to move within the cutting opening.

[0015] The beneficial effects of the film folding tracking and cutting mechanism disclosed in this utility model are as follows: through the mechanical adaptive structure of the swing assembly, the lateral thrust of the film folding edge on the guide edge is used as the driving force to make the swing arm swing around the fixed fulcrum, which drives the swing seat and the knife holder assembly on it to move as a whole, thereby tracking the fluctuation of the film tube width in real time. Without manual intervention or a complex electronic control system, the guide edge can always hook the folding edge, realizing the mechanical adaptive tracking and precise cutting of the film folding edge, and significantly improving product quality. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the film folding tracking cutter mechanism of this utility model.

[0017] Figure 2 This is an exploded view of the hot knife assembly on the knife holder in the film folding and tracking cutting mechanism of this utility model.

[0018] Figure 3 This is an exploded view of the film folding tracking cutter mechanism of this utility model.

[0019] Figure 4 This is a schematic diagram of the working state of the film folding tracking cutter mechanism of this utility model.

[0020] Figure 5 This is a schematic diagram of another working state of the film folding and tracking cutter mechanism of this utility model. Detailed Implementation

[0021] The present invention will be further described and illustrated below with reference to specific embodiments and the accompanying drawings: Please refer to Figure 1 A film folding tracking and cutting mechanism includes a cutter holder 10, a swing assembly 20, a sliding seat 30, a horizontal adjustment assembly 40, and a counterweight assembly 50. The cutter holder 10 is fixedly connected to one side of the swing assembly 20, and the other end of the swing assembly 20 is rotatably connected to the sliding seat 30. The sliding seat 30 is slidably mounted on the horizontal adjustment assembly 40, allowing the entire assembly to be adjusted horizontally. The counterweight assembly 50 is connected to the swing assembly 20 and provides a gravitational torque to the swing assembly 20, keeping the guide edge 11 of the cutter holder 10 in a state of adhering to and tightening the folded edge 2 of the film tube 1, thereby achieving an adaptive tracking function.

[0022] Please refer to Figure 2As shown, the knife holder 10 is provided with a guide edge 11 for hooking the folded edge 2 of the film tube 1. A cutting opening 111 is provided on the guide edge 11. The inner surface of the cutting opening 111 is an inclined surface or an arc surface, which is used to guide the blade of the hot cutting knife 123 and accommodate the blade to move within the cutting opening 111. A hot knife assembly 12 is also installed on the knife holder 10. The hot knife assembly 12 includes a heating unit 121, a clamping block 122, a hot cutting knife 123, and a movable block 124. The blade of the hot cutting knife 123 is correspondingly arranged with the cutting opening 111 on the guide edge 11 of the knife holder 10. The movable block 124 is fixedly connected to the clamping block 122. The movable block 124 is assembled on the swing seat 21 through an adjustable connection structure.

[0023] The heating unit 121 is connected to an external power source via a power cord. The heat generated is evenly transferred to the handle of the hot cutting blade 123 via the clamping block 122, causing the blade to heat up rapidly to the film melting temperature. The hot cutting blade 123 melts and cuts open the folded edge 2 of the film tube 1 by high-temperature melting. Compared with the traditional cold cutting method, the film is less deformed by force during cutting, and the cut edge is smooth and flat, without producing wavy edge defects.

[0024] Please refer to Figure 3 As shown, the swing assembly 20 is the adaptive tracking core of the mechanism, including a swing base 21, a first swing arm 221, and a second swing arm 222. The first swing arm 221 and the second swing arm 222 are arranged in parallel and are respectively connected to the swing base 21 and the sliding base 30 to form a parallelogram mechanism, ensuring that the swing base 21 remains unchanged in direction during movement.

[0025] The sliding seat 30 is rotatably mounted with a first rotating shaft 23 and a second rotating shaft 24, and the swing seat 21 is rotatably mounted with a third rotating shaft 25 and a fourth rotating shaft 26. The two ends of the first swing arm 221 are fixedly connected to the first rotating shaft 23 and the third rotating shaft 25, respectively, and the two ends of the second swing arm 222 are fixedly connected to the second rotating shaft 24 and the fourth rotating shaft 26, thereby realizing the rotational connection between the swing arm and the sliding seat 30 and the swing seat 21.

[0026] Specifically, the ends of the first rotating shaft 23 and the second rotating shaft 24 are machined with keyways, which are interference fit with the flat key at the end of the swing arm, facilitating quick disassembly and maintenance; the ends of the third rotating shaft 25 and the fourth rotating shaft 26 are machined with external threads, which pass through the through hole at the end of the swing arm and are locked and fixed by nuts. An elastic washer is provided between the two nuts to prevent loosening due to vibration, ensuring the reliability of the connection between the swing seat 21 and the swing arm.

[0027] The sliding seat 30 is a rectangular metal block with two parallel bearing mounting holes 31 inside along its thickness direction. Each bearing mounting hole 31 contains a retaining ring, a bushing, and a rolling bearing, forming a complete bearing assembly after assembly. The first rotating shaft 23 and the second rotating shaft 24 pass through the two bearing assemblies respectively, and are interference-fitted with the inner ring of the rolling bearing to achieve a low-friction rotational connection with the sliding seat 30, allowing the swing arm to swing flexibly under external force and respond to the adaptive tracking requirements when the film width fluctuates.

[0028] The swing seat 21 is also provided with the same bearing assembly as described above. The third rotating shaft 25 and the fourth rotating shaft 26 pass through the bearing assembly and are interference-fitted with the inner ring of the rolling bearing to achieve a low-friction rotational connection with the swing seat 21, so that the swing seat 21 can move flexibly under the action of external force and respond to the adaptive tracking requirements when the film width fluctuates.

[0029] When installing the rolling bearing, first place the bushing into the hole as a bearing seat, then install the rolling bearing into the inner hole of the bushing, and finally snap the retaining ring into the retaining ring groove at the opening of the hole. The retaining ring is used to snap into the retaining ring groove on the inner wall of the sliding seat 30 or the swing seat 21 to axially limit the outer ring of the rolling bearing, prevent the rolling bearing from coming out of the bearing mounting hole under the action of axial force, and ensure the stability and reliability of the shaft rotation.

[0030] In this embodiment, the bearing mounting structure is provided with two rolling bearings and two corresponding retaining rings. The two rolling bearings independently support the two rotating shafts, enabling the first swing arm 221 and the second swing arm 222 to achieve independent rotational degrees of freedom and higher sensitivity.

[0031] The horizontal adjustment assembly 40 includes a fixed plate 41, guide rods 42, and a first locking member 43. The two parallel guide rods 42 are connected to the fixed plate 41 by threaded fastening or welding. The sliding seat 30 has through holes on its side that mate with the guide rods 42. The sliding seat 30 is fitted onto the guide rods 42 through these through holes, forming a sliding fit. The first locking member 43 is a handle screw that radially passes through the side wall of the sliding seat 30 and abuts against the surface of the guide rods 42, used to lock the sliding seat 30 at any position on the guide rods 42.

[0032] In another embodiment, the horizontal adjustment component 40 can use an electric lead screw and nut pair instead of the manual sliding seat 30. Specifically, the guide rod 42 and the handle screw structure are eliminated, and a stepper motor and a ball screw are installed on the fixed plate 41. The sliding seat 30 has a nut machined inside to mate with the lead screw. When the film width specification changes, the operator inputs the target width value through the control panel, and the controller drives the stepper motor to rotate, causing the sliding seat 30 to automatically move along the lead screw to the target position. The position is controlled in a closed loop through encoder feedback. This results in high positioning accuracy, eliminates the need for manual locking, significantly reduces labor intensity, and is suitable for flexible production modes with multiple varieties and small batches.

[0033] The counterweight assembly 50 includes a counterweight block 51 and a support rod 52. The second rotating shaft 24 extends out of the sliding seat 30, and the extended end of the second rotating shaft 24 is fixedly connected to the support rod 52 by a key connection or threaded fastening. The counterweight block 51 is movably mounted on the support rod 52, and the support rod 52 is provided with a second locking member 53 for locking the position of the counterweight block 51 to prevent the counterweight block 51 from shifting under vibration conditions.

[0034] In this embodiment, the counterweight 51 adopts a stacked structure, that is, it is composed of multiple standard weight counterweight plates stacked together. The support rod 52 is machined with external threads, and a through hole is opened in the center of the counterweight plate. The counterweight plate is pressed and fixed to the support rod 52 by a nut. When it is necessary to adjust the counterweight force, it is only necessary to add or remove the number of counterweight plates and retighten the nut. The adjustment accuracy is higher, and the counterweight plates can be standardized and stocked, which is suitable for rapid changeover in the production of multiple types of films.

[0035] When conveying the film tube material 1, the initial positioning is first completed by the horizontal adjustment component 40: in manual mode, the first locking piece 43 is released, the sliding seat 30 is pushed to slide along the guide rod 42 to the preset position and then locked, realizing manual coarse adjustment; in electric mode, the parameters are input through the control panel, and the sliding seat 30 is automatically moved by the stepper motor and ball screw, and the encoder close-loop control of the positioning accuracy is adapted for quick changeover. After initial positioning, the counterweight assembly 50 provides a stable gravitational torque through the stacked counterweight block 51. The counterweight is added or removed according to the film material, and transmitted to the swing seat 21 through the support rod 52 and the second rotating shaft 24, so that the guide edge 11 of the knife holder 10 is tightly attached to and the folded edge 2 is tightened to counteract slight tension fluctuations.

[0036] Please refer to Figure 4 and Figure 5As shown, when the width of the film tube 1 deviates due to process fluctuations, the folded edge 2 of the film tube 1 exerts a lateral force on the guide edge 11, which is transmitted to the swing seat 21 via the tool holder 10. With the help of the parallelogram-structured swing assembly 20, the first and second swing arms swing synchronously along their respective connected shafts. The bearing assembly within the sliding seat 30 and the swing seat 21 ensures flexible rotation of the swing arms, driving the swing seat 21 to translate, so that the guide edge 11 always hooks onto the folded edge 2 of the film tube 1. At this time, the gravitational torque of the counterweight 51 and the lateral tension are dynamically balanced. When the width increases, the tension of the film tube 1 overcomes the counterweight 51, causing the swing seat to move to the left; when the width decreases, the gravitational torque pulls it back to its original position, achieving adaptive tracking of the folded edge. Meanwhile, the hot knife assembly 12 continues to operate. The heating unit 121 heats the hot cutting knife 123 via the clamping block 122. The blade melts and cuts open the folded edge 2 under the guidance of the cutting opening 111, ensuring a smooth cut. If the fluctuation exceeds the adaptive range, it can be readjusted through the horizontal adjustment assembly 40. The number of counterweights is adapted to the new specification film to ensure continuous production accuracy.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. A film folding tracking cutter mechanism, comprising a cutter holder, the cutter holder having a guide edge for hooking the folding edge of the film tube, characterized in that, It also includes a swing assembly, which includes a swing base and at least two swing arms. One end of each swing arm is hinged and the other end is connected to the swing base. The knife holder is fixed to the other side of the swing base. When the width of the film tube fluctuates, the guide edge, under the lateral thrust of the film folding edge, drives the swing base to achieve adaptive translation through the swing of the swing arms, so that the guide edge keeps hooking the film tube folding edge.

2. The film folding tracking cutter mechanism as described in claim 1, characterized in that, The swing arm includes a first swing arm and a second swing arm, the first swing arm and the second swing arm are arranged in parallel, and the first swing arm and the second swing arm are respectively connected to the swing seat to form a parallelogram mechanism.

3. The film folding tracking cutter mechanism as described in claim 2, characterized in that, The film folding tracking cutter mechanism also includes a sliding seat. Both the sliding seat and the swing seat are equipped with rolling bearings. One end of the first swing arm and the second swing arm are rotatably connected to the sliding seat through a first rotating shaft and a second rotating shaft, respectively. The first rotating shaft and the second rotating shaft are rotatably engaged with the sliding seat through the rolling bearings. The other end of the first swing arm and the second swing arm are rotatably connected to the swing seat through a third rotating shaft and a fourth rotating shaft, respectively. The third rotating shaft and the fourth rotating shaft are rotatably engaged with the swing seat through the rolling bearings.

4. The film folding tracking cutter mechanism as described in claim 3, characterized in that, When the width of the film tube fluctuates, the first and second swing arms swing synchronously around the axes of the first, second, third, and fourth rotating shafts, causing the swing seat to move horizontally while maintaining its direction.

5. The film folding tracking cutter mechanism as described in claim 3, characterized in that, The film folding tracking cutter mechanism also includes a horizontal adjustment component, which includes a fixed plate and a guide rod. The two ends of the guide rod are connected to the fixed plate, and the sliding seat is slidably disposed on the guide rod, so that the entire cutter mechanism can slide along the guide rod to adapt to film tubes of different widths.

6. The film folding tracking cutter mechanism as described in claim 5, characterized in that, A first locking member is provided on one side of the sliding seat. The first locking member passes through the sliding seat and cooperates with the guide rod to lock the sliding seat on the guide rod.

7. The film folding tracking cutter mechanism as described in claim 3, characterized in that, The film folding tracking cutter mechanism also includes a counterweight assembly, which includes a counterweight block and a support rod. The second rotating shaft extends out of the sliding seat and is connected to the support rod. The counterweight block is slidably mounted on the support rod to provide a force for the guide edge to tighten the film folding edge.

8. The film folding tracking cutter mechanism as described in claim 7, characterized in that, The support rod is provided with a second locking element for fixing the support rod to the second rotating shaft.

9. The film folding tracking cutter mechanism as described in claim 1, characterized in that, A hot knife assembly is installed on the knife holder. The hot knife assembly includes a heating unit, a clamping block, a hot cutting knife, and a movable block. The cutting edge of the hot cutting knife is correspondingly set with the cutting opening on the guide edge of the knife holder. The movable block is fixedly connected to the clamping block and is assembled on the swing seat through an adjustable connection structure.

10. The film folding tracking cutter mechanism as described in claim 9, characterized in that, The top of the guide edge is provided with an arc surface, and a cutting opening is provided on the guide edge. The inner surface of the cutting opening is an inclined surface or an arc surface, which is used to guide the blade of the hot cutting knife and accommodate the blade to move within the cutting opening.

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