Coating film guiding mechanism and double hot melt coating machine

Abstract

This invention discloses a coating film guiding mechanism for a dual hot melt coating machine and the dual hot melt coating machine itself. The coating film guiding mechanism includes a mounting frame, an infeed guide roller, an outfeed guide roller, a first linkage guiding unit, a second linkage guiding unit, a glue separation switching component, and a constant stroke compensation linkage component. Both the first and second linkage guiding units include a transverse flipping shaft, a first edge guide arm, a second edge guide arm, and a glue separation guide beam. The edge guide arm supports the uncoated edge areas on both sides of the coating film. The glue separation guide beam forms a non-contact glue-avoiding gap between its guiding position and the coating area of ​​the coating film. When the hot melt coating head retracts, the glue separation switching component drives the corresponding linkage guiding unit to flip to the glue separation position, so that the glue receiving groove of the glue separation guide beam faces downwards from the hot melt coating head to receive residual glue. This invention can simultaneously ensure stable guidance of the coating film edges, non-contact passage through wet glue areas, and glue separation during machine stop, reducing coating contamination and tension fluctuation risks.

Description

Technical Field

[0001] This invention relates to a coating film guiding mechanism, specifically to a coating film guiding mechanism and a dual hot melt coating machine. Background Technology

[0002] Hot melt coating machines are typically used to apply hot melt adhesive to the surface of films, paper, nonwoven fabrics, or composite substrates by methods such as coating, scraping, transfer coating, or spraying, to obtain coated film products with adhesive, laminating, sealing, or functional coatings. For some composite materials or functional films, in order to improve coating uniformity, increase coating efficiency, or achieve continuous forming of different adhesive layers, the production equipment adopts a dual hot melt coating structure. That is, two hot melt coating heads are arranged sequentially along the conveying direction of the coating film, so that the coating film continuously passes through two coating stations on the same conveying path, thereby completing the dual-station hot melt coating operation.

[0003] In the double hot melt coating process, the coated film needs to maintain stable tension and accurate guiding position throughout the unwinding, film feeding, first coating, transition conveying, second coating, and film exiting processes. Existing coating equipment typically uses fixed guide rollers, floating tension rollers, flattening rollers, correction rollers, or edge detection and correction mechanisms to guide and control the tension of the coated film. These structures can ensure the stability of film conveying to a certain extent. However, after the hot melt adhesive is applied to the surface of the coated film, before it has completely cooled and solidified, the surface of the coated area is prone to adhesion to guide rollers, support rollers, or other guiding components, leading to problems such as coating stringing, scratches, indentations, contamination, or uneven thickness in certain areas. Especially in dual hot melt coating machines, there is usually a transition guide zone between the first hot melt coating head and the second hot melt coating head. If ordinary guide rollers are used to directly support the coating film, it is easy to come into contact with the wet adhesive surface after coating. If the intermediate guide support is completely eliminated, the coating film is prone to sagging, deviation and shaking between the two coating stations due to its own weight, tension fluctuation or thermal deformation, which will affect the coating accuracy of the second coating station.

[0004] Meanwhile, during shutdowns, film replacements, film threading, maintenance, or cleaning, the hot melt coating head typically needs to be raised or lowered. At these times, residual hot melt adhesive inside the coating head may still drip onto the coating film or equipment surface due to gravity, residual pressure, or temperature changes. Existing equipment generally handles residual adhesive by temporarily placing a receiving tray under the coating head, installing a fixed adhesive baffle, or manually cleaning it. However, these structures lack a linkage with the coating film guiding mechanism. If the fixed adhesive receiving component is located near the film path for an extended period, it can easily affect the normal passage of the coating film; temporary receiving trays require manual operation, leading to problems such as missed placement, misalignment, and low efficiency; and ordinary adhesive baffles are insufficient to simultaneously fulfill both the adhesive-avoiding guiding function during normal coating and the residual adhesive receiving function during shutdown.

[0005] Furthermore, the film path between the two coating stations of a dual hot melt coating machine is relatively long. Changes in the effective path length of the coated film due to coating head lifting, guide component switching, tension roller floating, or local film path angle variations can all cause instantaneous tension fluctuations. For thin film materials, these instantaneous tension fluctuations can lead not only to lateral film displacement but also to changes in coating thickness, edge wrinkling, intermittent coating, or misalignment of the lamination position. While existing technologies include tension rollers or correction devices, these are typically independent adjustment mechanisms that cannot simultaneously compensate for the film path length during guide component state switching, nor can they coordinate the coating head retraction, guide component flipping, and film path compensation actions into a unified process.

[0006] Therefore, the existing coating film guiding mechanism of the dual hot melt coating machine still has the following shortcomings: First, ordinary guide rollers or support rollers are prone to contacting the wet adhesive area of ​​the coating film, causing coating contamination or damage; second, completely suspended conveying makes it difficult to ensure the stability of film material conveying between the two coating stations; third, when the coating head retracts or stops, the residual adhesive receiving structure and the guiding structure are independent of each other and cannot be automatically switched, resulting in poor reliability; fourth, the switching of the guiding structure easily changes the film path length, causing fluctuations in the coating film tension. Based on this, it is necessary to design a coating film guiding mechanism for a dual hot melt coating machine that can suspend and guide the uncoated edge of the coating film during normal coating, automatically switch to an adhesive receiving state when the coating head retracts, and synchronously compensate for changes in film path length. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a coating film guiding mechanism for a dual hot melt coating machine and the dual hot melt coating machine itself, which effectively overcomes the shortcomings of the prior art.

[0008] The present invention is achieved through the following technical solution: a coating film guiding mechanism for a dual hot melt coating machine, which is used to be installed on a dual hot melt coating machine having a first hot melt coating head and a second hot melt coating head, wherein the first hot melt coating head and the second hot melt coating head are spaced apart along the conveying direction of the coating film, and both can switch between a coating position close to the coating film and a retraction position far away from the coating film, characterized in that it includes a mounting frame, an infeed guide roller, an outfeed guide roller, a first linkage guiding unit, a second linkage guiding unit, an adhesive separation switching component, and a constant stroke compensation linkage component; The infeed guide roller and the outfeed guide roller are respectively rotatably mounted on the mounting frame. The infeed guide roller is located on the infeed side of the first hot melt coating head, and the outfeed guide roller is located on the outfeed side of the second hot melt coating head. The first linkage guide unit is disposed on the film exit side of the first hot melt coating head, and the second linkage guide unit is disposed on the film inlet side of the second hot melt coating head. An intermediate suspended film guide area for the coating film to pass through is formed between the first linkage guide unit and the second linkage guide unit. Both the first linkage guide unit and the second linkage guide unit include a lateral flipping shaft, a first edge guide arm, a second edge guide arm, and a sealant guide beam. The lateral flipping shaft is rotatably mounted on the mounting frame and extends along the width direction of the coated film. The first edge guide arm and the second edge guide arm are respectively located at both ends of the lateral flipping shaft and are respectively arranged corresponding to the uncoated edge areas on both sides of the width direction of the coated film. The sealant guide beam is connected to the lateral flipping shaft and is located between the first edge guide arm and the second edge guide arm. Both the first edge guide arm and the second edge guide arm have an edge film support surface for supporting the uncoated edge area of ​​the coated film. The adhesive-separating guide beam has a film guiding avoidance surface and an adhesive receiving groove located on the side opposite to the film guiding avoidance surface. The first edge guide arm, the second edge guide arm, and the adhesive-separating guide beam can be rotated synchronously between the guiding position and the adhesive-separating position with the lateral flipping axis. When the lateral flipping shaft is in the guide position, the edge film-supporting surfaces of the first edge guide arm and the second edge guide arm extend into the coating film conveying path and respectively support the uncoated edge areas on both sides of the coating film. The film-avoiding surface of the adhesive-separating guide beam is located below or to the side below the coating area of ​​the coating film and forms a non-contact adhesive-separating gap with the coating area of ​​the coating film, so that the coating area of ​​the coating film does not contact the adhesive-separating guide beam after passing the corresponding hot melt coating head. When the lateral flipping shaft is in the adhesive separation position, the first edge guide arm and the second edge guide arm retract from the support position for the uncoated edge area of ​​the coating film, and the adhesive receiving groove of the adhesive separation guide beam faces the lower side or the adhesive dispensing side of the corresponding hot melt coating head, which is used to receive the hot melt adhesive that falls from the corresponding hot melt coating head and form an adhesive barrier between the corresponding hot melt coating head and the coating film. The adhesive separation switching component is connected to the first hot melt coating head, the second hot melt coating head, the first linkage guide unit, and the second linkage guide unit respectively, so that when the first hot melt coating head switches from the coating position to the retraction position, it drives the first linkage guide unit to switch from the guide position to the adhesive separation position, and when the second hot melt coating head switches from the coating position to the retraction position, it drives the second linkage guide unit to switch from the guide position to the adhesive separation position. The constant-length compensation linkage component is connected between the first linkage guide unit and the second linkage guide unit. When the first linkage guide unit and / or the second linkage guide unit flips and switches, it drives the other linkage guide unit to generate a reverse compensation rotation or compensation displacement, so that the effective guide path length of the coating film between the infeed guide roller and the outfeed guide roller is kept within a preset compensation range.

[0009] As a preferred technical solution, both the first edge guide arm and the second edge guide arm include a connecting arm segment, an arc-shaped film support segment, and an inner adhesive barrier. The connecting arm segment is connected to the lateral flipping shaft. The arc-shaped film support segment is located at the end of the connecting arm segment away from the lateral flipping shaft. The edge film support surface is formed on the outer surface of the arc-shaped film support segment. The inner adhesive barrier extends from the arc-shaped film support segment toward the center of the coating film, and the inner adhesive barrier is arranged below the coating area of ​​the coating film to prevent hot melt adhesive from overflowing to the uncoated edge area of ​​the coating film.

[0010] As a preferred technical solution, the edge of the arc-shaped film support section transitions to an arc shape along the coating film conveying direction. The inlet end of the edge film support section is lower than the middle support section, and the outlet end of the edge film support section corresponds to the guide film height of the middle suspended guide film area. This allows the uncoated edge area of ​​the coating film to form a slightly arched guide state that transitions smoothly from low to high when passing through the edge film support section.

[0011] As a preferred technical solution, the adhesive guide beam includes a beam body, a heat insulation cavity, and a removable anti-stick liner. The adhesive receiving groove is formed on the side of the beam body facing the corresponding hot melt coating head. The heat insulation cavity is disposed along the length of the beam body between the adhesive receiving groove and the guide film clearance surface. The removable anti-stick liner is laid in the adhesive receiving groove to receive and isolate residual hot melt adhesive.

[0012] As a preferred technical solution, the adhesive separation switching assembly includes a first follow-up trigger, a second follow-up trigger, a first switching swing arm, a second switching swing arm, and a reset elastic element. The first follow-up trigger is connected to the lifting seat or swing seat of the first hot melt coating head, the second follow-up trigger is connected to the lifting seat or swing seat of the second hot melt coating head, the first switching swing arm is connected to the lateral flipping shaft of the first linkage guide unit, the second switching swing arm is connected to the lateral flipping shaft of the second linkage guide unit, and the reset elastic element is connected between the mounting frame and the corresponding switching swing arm, so that when the corresponding hot melt coating head returns to the coating position, the corresponding linkage guide unit can be reset from the adhesive separation position to the guide position.

[0013] As a preferred technical solution, a one-way clearance connection structure is provided between the first follower trigger and the first switching arm, and between the second follower trigger and the second switching arm. The one-way clearance connection structure includes an elongated hole connection portion and a toggle pin disposed in the elongated hole connection portion. When the corresponding hot melt coating head switches from the coating position to the clearance position, the toggle pin pushes the corresponding switching arm to rotate, and when the corresponding hot melt coating head returns from the clearance position to the coating position, the corresponding switching arm is allowed to independently reset under the action of the reset elastic member.

[0014] As a preferred technical solution, the constant-stroke compensation linkage component includes a first compensation wheel, a second compensation wheel, a cross drive belt, and a tension compensation wheel. The first compensation wheel is coaxially connected to the lateral tilting shaft of the first linkage guide unit, and the second compensation wheel is coaxially connected to the lateral tilting shaft of the second linkage guide unit. The cross drive belt is wound between the first compensation wheel and the second compensation wheel, so that the first linkage guide unit and the second linkage guide unit form a reverse linkage relationship. The tension compensation wheel is elastically pressed against the cross drive belt to absorb the instantaneous membrane path length change generated when the first linkage guide unit and the second linkage guide unit switch.

[0015] As a preferred technical solution, the first edge guide arm and the second edge guide arm of the first linkage guide unit and the second linkage guide unit are both set on the corresponding horizontal flipping axis through a horizontal adjustment seat. The horizontal adjustment seat can move and lock along the axial direction of the horizontal flipping axis to adjust the distance between the first edge guide arm and the second edge guide arm, so that the edge film support surface corresponds to the uncoated edge area of ​​the coating film of different widths.

[0016] As a preferred technical solution, the mounting bracket is further provided with a middle suspension limiting component, which is located between the first linkage guide unit and the second linkage guide unit. The middle suspension limiting component includes two lateral limiting blocks arranged at intervals along the width direction of the coating film. The two lateral limiting blocks are respectively provided for the uncoated edge areas on both sides of the coating film, and a middle adhesive-avoiding channel is formed between the two lateral limiting blocks to allow the coating area of ​​the coating film to pass through in the air.

[0017] This invention discloses a dual hot melt coating machine, comprising a machine base, a first hot melt coating head, a second hot melt coating head, and a coating film guiding mechanism. The coating film guiding mechanism includes a mounting frame, an infeed guide roller, an outfeed guide roller, a first linkage guiding unit, a second linkage guiding unit, a separation adhesive switching component, and a constant stroke compensation linkage component. The first hot melt coating head and the second hot melt coating head are disposed on the machine base along the coating film conveying direction. The infeed guide roller is located on the infeed side of the first hot melt coating head, and the outfeed guide roller is located on the outfeed side of the second hot melt coating head. The first linkage guiding unit is linked to the first hot melt coating head, and the second linkage guiding unit is linked to the second hot melt coating head, so that the coating film is suspended and guided by the uncoated edge areas on both sides during the dual hot melt coating process, and the coating area of ​​the coating film passes through the first hot melt coating head and the second hot melt coating head in a non-contact manner.

[0018] The beneficial effects of the present invention are as follows: By setting up a first linkage guide unit and a second linkage guide unit, and by making the first edge guide arm, the second edge guide arm and the adhesive-separating guide beam in each linkage guide unit switch synchronously with the transverse flipping axis, the same set of structures can support the uncoated edge areas on both sides of the coated film through the edge film support surface during normal coating, while keeping the middle coating area of ​​the coated film and the adhesive-separating guide beam in a non-contact adhesive-avoiding gap. This ensures the stability of the coating film conveying between the dual hot melt coating stations and avoids the guide components from contacting the wet adhesive surface, which could cause adhesive sticking, stringing, scratches or coating indentations.

[0019] The adhesive-isolating guide beam of the present invention is used as an adhesive-avoiding guide component in the guiding state. In the adhesive-isolating position, it can also be directed towards the lower side or the adhesive dispensing side of the corresponding hot melt coating head through the adhesive receiving tank to receive the hot melt adhesive remaining on the coating head and form an adhesive barrier between the coating head and the coating film. This transforms the component originally used for guiding the film to avoid obstacles into a residual adhesive receiving component when the machine is stopped, the film is changed, or it is cleaned. It realizes a multi-purpose linkage structure function and reduces the need for additional adhesive receiving trays or manual placement of adhesive blocking components.

[0020] This invention establishes a mechanical linkage between the coating position and retraction position of the hot melt coating head and the guiding position and retraction position of the corresponding linkage guiding unit through a glue-separating switching component. This allows the hot melt coating head to synchronously drive the corresponding linkage guiding unit to flip to the glue-separating position when it retracts, and to reset to the guiding position when it returns to the coating position. This avoids the problems of missed switching, misalignment, or interference caused by separate operation of the guiding structure and the glue-receiving structure, and improves the automation and reliability of the equipment operation.

[0021] This invention establishes a reverse compensation linkage relationship between the first linkage guide unit and the second linkage guide unit through a constant-length compensation linkage component. When one or two linkage guide units switch over, the change in film path length can be absorbed and compensated by the compensation wheel, cross transmission belt and tension compensation wheel, so that the effective guide path length of the coating film between the infeed guide roller and the outfeed guide roller is kept within the preset compensation range. This reduces the impact of the guide state switching on the tension of the coating film and reduces the risk of film deviation, wrinkling and coating thickness fluctuation.

[0022] This invention uses a central suspended limiting component and lateral limiting blocks to limit the uncoated edge areas on both sides of the coated film, and forms a central adhesive-avoiding channel between the two lateral limiting blocks. This allows the coating area of ​​the coated film to remain suspended between the first hot melt coating head and the second hot melt coating head, which helps to ensure the integrity and cleanliness of the coating area, while improving the guiding accuracy and product consistency in the dual hot melt continuous coating process. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of the coating film guiding mechanism of the dual hot melt coating machine of the present invention; Figure 2 This is a partial structural diagram of the first linkage guide unit in the present invention when it is in the guide position; Figure 3 This is a partial structural diagram of the first linkage guide unit in the present invention when it is in the adhesive separation position; Figure 4 This is a schematic diagram illustrating the linkage relationship between the first linkage guide unit, the second linkage guide unit, and the constant stroke compensation linkage component in this invention.

[0024] Explanation of reference numerals in the attached figures: 1. Mounting frame; 2. Infeed guide roller; 3. Outfeed guide roller; 4. First hot melt coating head; 5. Second hot melt coating head; 6. First linkage guide unit; 7. Second linkage guide unit; 8. Intermediate suspended film guiding area; 9. Adhesive separation switching assembly; 10. Constant stroke compensation linkage assembly; 11. Lateral flipping shaft; 12. First edge guide arm; 13. Second edge guide arm; 14. Adhesive separation guide beam; 15. Edge film support surface; 16. Guide... 17. Membrane clearance surface; 18. Adhesive receiving tank; 19. First follow-up trigger; 20. Second follow-up trigger; 21. First switching swing arm; 22. Second switching swing arm; 23. Reset elastic element; 24. First compensation wheel; 25. Second compensation wheel; 26. Cross drive belt; 27. Tensioning compensation wheel; 28. Lateral adjustment seat; 29. ​​Middle suspension limit element; 30. Lateral limit block; 31. Coated film; 32. Middle adhesive clearance channel. Detailed Implementation

[0025] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0026] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features for a similar purpose, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0027] Combination Figures 1 to 4As shown, this embodiment provides a coating film guiding mechanism for a dual hot melt coating machine. This mechanism is installed on the machine base of the dual hot melt coating machine and is used to stably guide the coating film 30 as it sequentially passes through the first hot melt coating head 4 and the second hot melt coating head 5. It also suspends and supports the uncoated edge areas on both sides of the coating film 30 without contacting the central coating area. The first hot melt coating head 4 and the second hot melt coating head 5 are spaced apart along the conveying direction of the coating film 30. The first hot melt coating head 4 is located at the preceding coating station of the coating film 30, and the second hot melt coating head 5 is located at the following coating station. Both can switch between a coating position close to the coating film 30 and a retraction position away from the coating film 30 according to coating, shutdown, film replacement, or cleaning needs. When the equipment is in normal coating state, the first hot melt coating head 4 and the second hot melt coating head 5 approach the coating film 30 and apply hot melt adhesive to the coating film 30; when the equipment is stopped, the film is inserted, the film is replaced, or residual adhesive is cleaned, the first hot melt coating head 4 and the second hot melt coating head 5 can be moved upward or swung away from the coating film 30 to leave space for film circuit operation and residual adhesive treatment.

[0028] The coating film guiding mechanism includes a mounting frame 1, an infeed guide roller 2, an outfeed guide roller 3, a first linkage guiding unit 6, a second linkage guiding unit 7, an adhesive separation switching assembly 9, and a constant stroke compensation linkage assembly 10. The mounting frame 1 serves as the basic mounting structure for all guiding, linkage, support, and compensation components. It can be fixed to the machine base of the dual hot melt coating machine, or it can be integrally formed with the machine base or fixedly connected via bolts, connecting plates, reinforcing ribs, or other structures. The infeed guide roller 2 is rotatably mounted on the infeed side of the mounting frame 1, used to receive the coating film 30 from the upstream unwinding mechanism or the preceding conveying mechanism, and guide the coating film 30 into the area where the first hot melt coating head 4 is located. The outfeed guide roller 3 is rotatably mounted on the outfeed side of the mounting frame 1, used to guide the coating film 30 after passing through the first hot melt coating head 4 and the second hot melt coating head 5 to the subsequent cooling, laminating, winding, or inspection mechanism. The infeed guide roller 2 is located on the infeed side of the first hot melt coating head 4, and the exit guide roller 3 is located on the exit side of the second hot melt coating head 5, so that the coated film 30 can form a continuous conveying path along the infeed guide roller 2, the first hot melt coating head 4, the first linkage guide unit 6, the intermediate suspended guide film area 8, the second linkage guide unit 7, the second hot melt coating head 5 and the exit guide roller 3 in sequence.

[0029] The first linkage guide unit 6 is disposed on the exit side of the first hot melt coating head 4, and is used to guide the edge of the coating film 30 that has not yet completely cooled and solidified after passing through the first hot melt coating head 4. The second linkage guide unit 7 is disposed on the inlet side of the second hot melt coating head 5, and is used to reposition and guide the coating film 30 before it enters the second hot melt coating head 5. An intermediate suspended guide film area 8 is formed between the first linkage guide unit 6 and the second linkage guide unit 7. The intermediate suspended guide film area 8 is used to keep the coating film 30 suspended between the first hot melt coating head 4 and the second hot melt coating head 5, especially to prevent the central coating area of ​​the coating film 30 from contacting the guide roller, support plate or other rigid guide components, thereby avoiding adhesion, stringing, scratches, indentations or thickness fluctuations of the hot melt adhesive coating before it stabilizes.

[0030] Both the first linkage guide unit 6 and the second linkage guide unit 7 include a transverse flipping shaft 11, a first edge guide arm 12, a second edge guide arm 13, and a sealant guide beam 14. The transverse flipping shaft 11 is rotatably mounted on the mounting frame 1 and extends along the width direction of the coated film 30. The first edge guide arm 12 and the second edge guide arm 13 are respectively located at both ends of the transverse flipping shaft 11 and are respectively arranged corresponding to the uncoated edge areas on both sides of the width direction of the coated film 30. The sealant guide beam 14 is connected to the transverse flipping shaft 11 and is located between the first edge guide arm 12 and the second edge guide arm 13. Since the first edge guide arm 12, the second edge guide arm 13, and the sealant guide beam 14 are all linked with the transverse flipping shaft 11, when the transverse flipping shaft 11 rotates, the first edge guide arm 12, the second edge guide arm 13, and the sealant guide beam 14 can synchronously switch postures, so that the same linkage guide unit can perform both film support and sealant receiving functions under different working conditions.

[0031] Specifically, both the first edge guide arm 12 and the second edge guide arm 13 have edge film support surfaces 15, which are used to support the uncoated edge areas on both sides of the coated film 30. Since hot melt adhesive is usually applied to the central area or a designated coating area of ​​the coated film 30, while the two side edges can retain uncoated edges, the edge film support surfaces 15 only contact and support the uncoated edge areas, avoiding contact with the central coating area. The adhesive-separating guide beam 14 has a film-guiding clearance surface 16 and an adhesive receiving groove 17 located on the opposite side of the film-guiding clearance surface 16. The film-guiding clearance surface 16 is used to face the central coating area of ​​the coated film 30 in the guiding state and maintain a non-contact adhesive-separating gap with the central coating area; the adhesive receiving groove 17 is used to face the lower side or the dispensing side of the corresponding hot melt coating head in the adhesive-separating state to receive the hot melt adhesive remaining from the hot melt coating head. Therefore, the adhesive-insulating guide beam 14 is not simply used as a fixed guide component, but forms an adhesive-avoiding support auxiliary structure and a residual adhesive receiving and isolation structure in different flipping positions.

[0032] like Figure 2 As shown, when the transverse flipping shaft 11 is in the guide position, the first edge guide arm 12 and the second edge guide arm 13 rotate with the transverse flipping shaft 11 to extend into the conveying path of the coating film 30. The two edge film-supporting surfaces 15 are located below or to the side below the two sides of the coating film 30 in the width direction, respectively, and support the uncoated edge areas on both sides of the coating film 30. At this time, the central coating area of ​​the coating film 30 is located between the two edge film-supporting surfaces 15 and is in a relatively suspended state. The guide film avoidance surface 16 of the adhesive-separating guide beam 14 is located below or to the side below the coating area of ​​the coating film 30. A non-contact adhesive-separating gap is formed between the guide film avoidance surface 16 and the coating area of ​​the coating film 30, so that the wet adhesive area of ​​the coating film 30 will not contact the adhesive-separating guide beam 14 after passing through the first hot melt coating head 4 or the second hot melt coating head 5. This structure allows the coated film 30 to obtain the necessary edge support and guidance, while also allowing the central coating area to pass through without contact, thus balancing guiding stability and coating integrity.

[0033] like Figure 3 As shown, when the lateral tilting shaft 11 is in the adhesive-isolating position, the first edge guide arm 12 and the second edge guide arm 13 rotate with the lateral tilting shaft 11 and retract from the supporting position for the uncoated edge area of ​​the coated film 30, avoiding unnecessary clamping or interference to the coated film 30 during shutdown, film replacement, or cleaning. Simultaneously, the adhesive-isolating guide beam 14 tilts to a position where the adhesive receiving tank 17 faces downwards or towards the adhesive dispensing side of the corresponding hot melt coating head, allowing the adhesive receiving tank 17 to be positioned between the corresponding hot melt coating head and the coated film 30 or near the hot melt adhesive's falling path. When residual adhesive is generated during the retraction, shutdown, or dripping of residual adhesive from the first hot melt coating head 4 or the second hot melt coating head 5, the adhesive receiving tank 17 can collect the residual hot melt adhesive and form an adhesive barrier between the corresponding hot melt coating head and the coated film 30, preventing residual adhesive from dripping directly onto the surface of the coated film 30 or into the equipment. Thus, the same adhesive-isolating guide beam 14 does not contact the wet adhesive surface during normal coating, but transforms into an adhesive-bearing and adhesive-blocking component when the machine stops or retracts, realizing the linkage conversion between the guiding function and the adhesive-isolating function.

[0034] Both the first edge guide arm 12 and the second edge guide arm 13 may include a connecting arm segment, an arc-shaped film support segment, and an inner adhesive barrier. The connecting arm segment is connected to the lateral flipping shaft 11, allowing the edge guide arm to rotate synchronously with the lateral flipping shaft 11. The arc-shaped film support segment is located at the end of the connecting arm segment away from the lateral flipping shaft 11, and the edge film support surface 15 is formed on the outer surface of the arc-shaped film support segment. By setting the film support area to an arc-shaped structure, the uncoated edge area of ​​the coated film 30 can achieve a smooth transition when entering the edge film support surface 15, reducing scratches, wrinkles, or stress concentrations caused by local corners on the film edge. The inner adhesive barrier extends from the arc-shaped film support segment toward the center of the coated film 30, and the inner adhesive barrier is arranged below the coating area of ​​the coated film 30, so that it can block the hot melt adhesive that may flow or spread to both sides without contacting the wet adhesive surface in the middle, reducing the risk of hot melt adhesive overflowing to the uncoated edge area.

[0035] The edge support surface 15 of the arc-shaped support section transitions to an arc shape along the conveying direction of the coated film 30. The inlet end of the edge support surface 15 is lower than the middle support section, and the outlet end of the edge support surface 15 corresponds to the guide height of the middle suspended guide film area 8. When the coated film 30 passes through the edge support surface 15, its uncoated edge areas on both sides can form a micro-arched guide state that transitions smoothly from low to high. This micro-arched guide state can provide slight support and flattening to the edges of the coated film 30 without forcibly compressing the middle coating area, thereby reducing lateral sway and edge slack of the film material and improving the flatness and positional stability of the coated film 30 before entering the second hot melt coating head 5. Since the edge support surface 15 only acts on the uncoated edge area, it will not damage the wet adhesive layer in the middle of the coated film 30.

[0036] The adhesive-sealing guide beam 14 may include a beam body, a heat insulation cavity, and a removable anti-stick liner. The beam body serves as the load-bearing foundation of the adhesive-sealing guide beam 14 and can be fixedly connected to the lateral tilting shaft 11 or a corresponding linkage arm so that it can tilt synchronously with the lateral tilting shaft 11. An adhesive receiving groove 17 is formed on the side of the beam body facing the corresponding hot-melt coating head. When the adhesive-sealing guide beam 14 is in the adhesive-sealing position, the adhesive receiving groove 17 faces the direction in which the hot-melt adhesive may drip. The heat insulation cavity is disposed along the length of the beam body between the adhesive receiving groove 17 and the guiding film clearance surface 16. The heat insulation cavity reduces the heat transfer from the high-temperature residual adhesive in the adhesive receiving groove 17 to the guiding film clearance surface 16, preventing the adhesive-sealing guide beam 14 from excessively heating the adjacent membrane material due to excessively high residual adhesive temperature. The removable anti-stick liner is laid in the adhesive receiving tank 17. The residual hot melt adhesive drips down and mainly adheres to the removable anti-stick liner. During cleaning, the removable anti-stick liner can be removed for replacement or cleaning, thereby reducing direct pollution to the main beam and improving maintenance convenience.

[0037] The adhesive-separation switching assembly 9 is used to link the retraction action of the hot melt coating head with the flipping action of the corresponding linkage guide unit. The adhesive-separation switching assembly 9 includes a first follower trigger 18, a second follower trigger 19, a first switching swing arm 20, a second switching swing arm 21, and a reset elastic element 22. The first follower trigger 18 is connected to the lifting seat or swing seat of the first hot melt coating head 4 and can move synchronously with the lifting or swinging action of the first hot melt coating head 4. The second follower trigger 19 is connected to the lifting seat or swing seat of the second hot melt coating head 5 and can move synchronously with the lifting or swinging action of the second hot melt coating head 5. The first switching swing arm 20 is connected to the lateral flipping shaft 11 of the first linkage guide unit 6, and the second switching swing arm 21 is connected to the lateral flipping shaft 11 of the second linkage guide unit 7. The reset elastic element 22 is connected between the mounting bracket 1 and the corresponding switching swing arm, and is used to push or pull the corresponding switching swing arm to reset after the external triggering action is released, thereby allowing the corresponding linkage guide unit to return from the adhesive-separation position to the guide position.

[0038] When the first hot melt coating head 4 switches from the coating position to the retraction position, the first follower trigger 18 moves with the first hot melt coating head 4 and acts on the first switching swing arm 20. The first switching swing arm 20 drives the lateral flipping shaft 11 of the first linkage guide unit 6 to rotate, so that the first edge guide arm 12, the second edge guide arm 13, and the adhesive-isolating guide beam 14 simultaneously flip from the guide position to the adhesive-isolating position. At this time, the first linkage guide unit 6 is no longer used as an edge film support structure, but rather the adhesive receiving groove 17 of the adhesive-isolating guide beam 14 faces downward or towards the adhesive dispensing side of the first hot melt coating head 4, so as to receive the hot melt adhesive remaining in the first hot melt coating head 4. Correspondingly, when the second hot melt coating head 5 switches from the coating position to the retraction position, the second follower trigger 19 moves with the second hot melt coating head 5 and acts on the second switching swing arm 21. The second switching swing arm 21 drives the lateral flipping shaft 11 of the second linkage guide unit 7 to rotate, so that the second linkage guide unit 7 switches from the guide position to the adhesive-isolating position. With the above settings, the retraction action of the first hot melt coating head 4 and the second hot melt coating head 5 can directly drive the corresponding linkage guide unit to switch states, without the need for manual placement of the glue receiving tray or separate operation of the glue blocking component.

[0039] One-way clearance connection structures can be provided between the first follower trigger 18 and the first switching swing arm 20, and between the second follower trigger 19 and the second switching swing arm 21. The one-way clearance connection structure includes an elongated hole connection portion and a deflecting pin disposed within the elongated hole connection portion. When the corresponding hot melt coating head switches from the coating position to the clearance position, the deflecting pin pushes the corresponding switching swing arm to rotate, causing the linkage guide unit to switch to the adhesive-separating position. When the corresponding hot melt coating head returns from the clearance position to the coating position, the deflecting pin can generate relative sliding or clearance within the elongated hole connection portion, allowing the corresponding switching swing arm to independently and smoothly return to the guide position under the action of the reset elastic element 22. This one-way clearance connection structure avoids the forced impact of the hot melt coating head's reset action on the linkage guide unit, while allowing the linkage guide unit to return to the edge film-supporting state in a gentler manner under the action of the reset elastic element 22, which helps reduce the risk of the film material being suddenly lifted or scratched.

[0040] like Figure 1 and Figure 4 As shown, the constant-stroke compensation linkage assembly 10 is connected between the first linkage guide unit 6 and the second linkage guide unit 7, and is used to compensate for the effective guide path length of the coating film 30 between the infeed guide roller 2 and the outlet guide roller 3 when the first linkage guide unit 6 and / or the second linkage guide unit 7 flips and switches. The constant-stroke compensation linkage assembly 10 includes a first compensation wheel 23, a second compensation wheel 24, a cross drive belt 25, and a tension compensation wheel 26. The first compensation wheel 23 is coaxially connected to the lateral flipping shaft 11 of the first linkage guide unit 6, and the second compensation wheel 24 is coaxially connected to the lateral flipping shaft 11 of the second linkage guide unit 7. The cross drive belt 25 is wound between the first compensation wheel 23 and the second compensation wheel 24, so that the first linkage guide unit 6 and the second linkage guide unit 7 form a reverse linkage relationship. The tension compensation wheel 26 is elastically pressed against the cross drive belt 25, and is used to absorb the tension change of the cross drive belt 25 during the flipping and switching process of the first linkage guide unit 6 and the second linkage guide unit 7, and to buffer the instantaneous change in film path length.

[0041] When the first linkage guide unit 6 flips due to the retraction of the first hot melt coating head 4, the lateral flipping shaft 11 of the first linkage guide unit 6 drives the first compensation wheel 23 to rotate. The first compensation wheel 23 drives the second compensation wheel 24 to rotate in the opposite direction through the cross transmission belt 25, thereby enabling the second linkage guide unit 7 to generate reverse compensation rotation or compensation displacement. The reverse compensation movement can offset the local change in film path length caused by the flipping of the first linkage guide unit 6, keeping the effective guide path length of the coating film 30 between the infeed guide roller 2 and the outfeed guide roller 3 within the preset compensation range. Conversely, when the second linkage guide unit 7 flips, the second compensation wheel 24 drives the first compensation wheel 23 to generate a reverse compensation action through the cross transmission belt 25, which can also reduce the change in film path length. The tension compensation wheel 26 elastically presses against the cross transmission belt 25, keeping the cross transmission belt 25 at a proper tension and absorbing the impact or gap that may occur at the moment of switching, thereby reducing the risk of sudden tension changes, lateral deviation, edge wrinkling, or coating thickness fluctuations in the coating film 30 during the switching of the guiding state.

[0042] To accommodate coating films 30 of varying widths, the first edge guide arm 12 and the second edge guide arm 13 of the first linkage guide unit 6 and the second linkage guide unit 7 are both mounted on the corresponding transverse flip axis 11 via a transverse adjustment seat 27. The transverse adjustment seat 27 can move and lock along the axial direction of the transverse flip axis 11, allowing the distance between the first edge guide arm 12 and the second edge guide arm 13 to be adjusted according to the width of the coating film 30. During adjustment, the locking mechanism of the transverse adjustment seat 27 can be loosened, and the first edge guide arm 12 and the second edge guide arm 13 can be moved to the positions of the uncoated edge areas on both sides of the coating film 30, respectively. Then, the transverse adjustment seat 27 is locked, ensuring that the edge support surface 15 accurately aligns with the uncoated edge areas on both sides of the coating film 30. This structure allows the coating film guiding mechanism to be applicable to various film materials while maintaining the relative relationship between the edge support and the central adhesive avoidance after adjustment.

[0043] The mounting bracket 1 is also equipped with a central suspension limiting member 28, which is located between the first linkage guide unit 6 and the second linkage guide unit 7, and corresponds to the central suspension guide film area 8. The central suspension limiting member 28 includes two lateral limiting blocks 29 spaced apart along the width direction of the coating film 30, with the two lateral limiting blocks 29 respectively corresponding to the uncoated edge areas on both sides of the coating film 30. A central adhesive-avoiding channel 31 is formed between the two lateral limiting blocks 29, allowing the coating area of ​​the coating film 30 to pass through in a suspended manner. When the coating film 30 passes through the central suspension guide film area 8, the uncoated edge areas on both sides can be limited and guided by the lateral limiting blocks 29, while the central coating area passes through in a suspended manner within the central adhesive-avoiding channel 31. The lateral limiting block 29 can limit the coating film 30 from excessive lateral displacement between the two hot melt coating stations, and the central adhesive avoidance channel 31 can avoid contact interference with the central coating of the coating film 30, thereby further ensuring the guiding accuracy and coating integrity of the coating film 30 between the first hot melt coating head 4 and the second hot melt coating head 5.

[0044] In actual operation, the coated film 30 first enters the area of ​​the first hot melt coating head 4 via the film guide roller 2. The first hot melt coating head 4 applies the first hot melt adhesive to the coated film 30 at the coating position. After passing the first hot melt coating head 4, the coated film 30 enters the area of ​​the first linkage guide unit 6. At this time, the first linkage guide unit 6 is in the guiding position. The edge film support surfaces 15 of the first edge guide arm 12 and the second edge guide arm 13 respectively support the uncoated edge areas on both sides of the coated film 30. The central coated area of ​​the coated film 30 passes through the two edge film support surfaces 15 in a suspended manner, maintaining a non-contact adhesive avoidance gap with the film avoidance surface 16 of the adhesive avoidance guide beam 14. Subsequently, the coated film 30 enters the central suspended film guide area 8. The uncoated edge areas on both sides are limited by the lateral limit blocks 29 of the central suspended limit member 28, and the central coated area passes through the central adhesive avoidance channel 31 in a suspended manner. Afterwards, the coated film 30 enters the area where the second linkage guide unit 7 is located. The second linkage guide unit 7 also suspends and guides the uncoated edge areas on both sides of the coated film 30 through the first edge guide arm 12 and the second edge guide arm 13, so that the coated film 30 enters the second hot melt coating head 5 in a stable posture. The second hot melt coating head 5 applies a second hot melt adhesive to the coated film 30. Finally, the coated film 30 is discharged through the film exit guide roller 3.

[0045] When it is necessary to stop the machine, change the film, clean, or maintain the hot melt coating head, the first hot melt coating head 4 and / or the second hot melt coating head 5 switch from the coating position to the retraction position. The corresponding follow-up trigger moves with the hot melt coating head and drives the lateral flip shaft 11 of the corresponding linkage guide unit to rotate through the corresponding switching swing arm, so that the first edge guide arm 12 and the second edge guide arm 13 retract from the edge support position, and at the same time, the adhesive separation guide beam 14 flips to the adhesive separation position where the adhesive receiving tank 17 faces the bottom of the hot melt coating head or the adhesive dispensing side. At this time, even if the hot melt adhesive remaining in the hot melt coating head falls due to gravity, residual pressure, or temperature changes, it will be preferentially received by the adhesive receiving tank 17 and will not drip directly onto the coating film 30. At the same time, the constant-length compensation linkage component 10 compensates for the path changes during the flipping process of the linkage guide unit through the first compensation wheel 23, the second compensation wheel 24, the cross transmission belt 25 and the tension compensation wheel 26, so that the effective guide path length of the coating film 30 is limited to the preset compensation range, and the film material is prevented from suddenly loosening or tightening due to the switching of the guide unit.

[0046] When the hot melt coating head returns to the coating position, the one-way clearance connection structure allows the corresponding switching swing arm to smoothly reset under the action of the reset elastic element 22, so that the corresponding linkage guide unit returns from the adhesive-isolating position to the guide position. The first edge guide arm 12 and the second edge guide arm 13 re-extend into the under or side-below of the uncoated edge areas on both sides of the coating film 30, and the edge film support surface 15 resumes its suspension and guiding function on the edge of the coating film 30. The film-avoiding surface 16 of the adhesive-isolating guide beam 14 is once again located under or side-below the coating area in the middle of the coating film 30 and maintains a non-contact adhesive-avoiding gap with the coating film 30. Thus, the coating film guiding mechanism can reliably switch between normal coating, shutdown adhesive isolation, film replacement cleaning, and recoating, and maintain the stability of the film path length and guiding relationship during the switching process.

[0047] This embodiment also provides a dual hot melt coating machine, which includes a machine base, a first hot melt coating head 4, a second hot melt coating head 5, and a coating film guiding mechanism. The mounting frame 1 in the coating film guiding mechanism can be fixedly mounted on the machine base. The first hot melt coating head 4 and the second hot melt coating head 5 are positioned on the machine base along the conveying direction of the coating film 30. The infeed guide roller 2 is located on the infeed side of the first hot melt coating head 4, and the outlet guide roller 3 is located on the outlet side of the second hot melt coating head 5. A first linkage guiding unit 6 is linked to the first hot melt coating head 4, and a second linkage guiding unit 7 is linked to the second hot melt coating head 5, so that the coating film 30 is suspended and guided by the uncoated edge areas on both sides during the dual hot melt coating process, and the coating area of ​​the coating film 30 remains non-contact between the first hot melt coating head 4 and the second hot melt coating head 5. With this structure, the dual hot melt coating machine can reduce the risk of wet adhesive surface being contaminated by the guide components while ensuring the stability of the film material guidance. It can also automatically form an adhesive-receiving state when the hot melt coating head retracts or stops, thereby improving the stability, cleanliness and maintenance convenience of the dual hot melt continuous coating process.

[0048] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions conceived without inventive effort should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A coating film guiding mechanism for a dual hot melt coating machine, used to be installed on a dual hot melt coating machine having a first hot melt coating head (4) and a second hot melt coating head (5), wherein the first hot melt coating head (4) and the second hot melt coating head (5) are spaced apart along the conveying direction of the coating film (30), and both are capable of switching between a coating position close to the coating film (30) and a retraction position away from the coating film (30), characterized in that, It includes a mounting frame (1), a film inlet guide roller (2), a film outlet guide roller (3), a first linkage guide unit (6), a second linkage guide unit (7), a glue separation switching assembly (9), and a constant stroke compensation linkage assembly (10). The infeed guide roller (2) and the outfeed guide roller (3) are respectively rotatably mounted on the mounting frame (1). The infeed guide roller (2) is located on the infeed side of the first hot melt coating head (4), and the outfeed guide roller (3) is located on the outfeed side of the second hot melt coating head (5). The first linkage guide unit (6) is disposed on the film exit side of the first hot melt coating head (4), and the second linkage guide unit (7) is disposed on the film inlet side of the second hot melt coating head (5). An intermediate suspended guide film area (8) is formed between the first linkage guide unit (6) and the second linkage guide unit (7) for the coating film (30) to pass through. The first linkage guide unit (6) and the second linkage guide unit (7) both include a transverse flip shaft (11), a first edge guide arm (12), a second edge guide arm (13), and a glue-separating guide beam (14). The transverse flip shaft (11) is rotatably mounted on the mounting frame (1) and extends along the width direction of the coating film (30). The first edge guide arm (12) and the second edge guide arm (13) are respectively located at the two ends of the transverse flip shaft (11) and are respectively arranged corresponding to the uncoated edge areas on both sides of the width direction of the coating film (30). The glue-separating guide beam (14) is connected to the transverse flip shaft (11) and located between the first edge guide arm (12) and the second edge guide arm (13). The first edge guide arm (12) and the second edge guide arm (13) each have an edge film support surface (15) for supporting the uncoated edge area of ​​the coated film (30). The adhesive-separating guide beam (14) has a film guiding avoidance surface (16) and an adhesive receiving groove (17) located on the opposite side of the film guiding avoidance surface (16). The first edge guide arm (12), the second edge guide arm (13) and the adhesive-separating guide beam (14) can be rotated synchronously between the guiding position and the adhesive-separating position with the transverse flipping axis (11). When the transverse flipping shaft (11) is in the guide position, the edge film support surface (15) of the first edge guide arm (12) and the second edge guide arm (13) extends into the conveying path of the coating film (30) and supports the uncoated edge areas on both sides of the coating film (30). The guide film avoidance surface (16) of the adhesive barrier guide beam (14) is located below or to the side below the coating area of ​​the coating film (30) and forms a non-contact adhesive avoidance gap with the coating area of ​​the coating film (30), so that the coating area of ​​the coating film (30) does not contact the adhesive barrier guide beam (14) after passing the corresponding hot melt coating head. When the lateral flipping shaft (11) is in the adhesive separation position, the first edge guide arm (12) and the second edge guide arm (13) retract from the support position for the uncoated edge area of ​​the coating film (30), and the adhesive receiving groove (17) of the adhesive separation guide beam (14) faces the lower side or the adhesive dispensing side of the corresponding hot melt coating head, which is used to receive the hot melt adhesive that falls from the corresponding hot melt coating head and form an adhesive separation barrier between the corresponding hot melt coating head and the coating film (30). The adhesive separation switching assembly (9) is connected to the first hot melt coating head (4), the second hot melt coating head (5), the first linkage guide unit (6), and the second linkage guide unit (7) respectively. When the first hot melt coating head (4) switches from the coating position to the retraction position, it drives the first linkage guide unit (6) to switch from the guide position to the adhesive separation position. When the second hot melt coating head (5) switches from the coating position to the retraction position, it drives the second linkage guide unit (7) to switch from the guide position to the adhesive separation position. The constant-length compensation linkage component (10) is connected between the first linkage guide unit (6) and the second linkage guide unit (7). When the first linkage guide unit (6) and / or the second linkage guide unit (7) are flipped and switched, the other linkage guide unit is driven to generate reverse compensation rotation or compensation displacement so that the effective guide path length of the coating film (30) between the infeed guide roller (2) and the outfeed guide roller (3) is kept within the preset compensation range.

2. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, Both the first edge guide arm (12) and the second edge guide arm (13) include a connecting arm segment, an arc-shaped film support segment, and an inner adhesive barrier. The connecting arm segment is connected to the lateral flipping shaft (11). The arc-shaped film support segment is located at one end of the connecting arm segment away from the lateral flipping shaft (11). The edge film support surface (15) is formed on the outer side of the arc-shaped film support segment. The inner adhesive barrier extends from the arc-shaped film support segment toward the middle of the coating film (30) and is arranged below the coating area of ​​the coating film (30) to prevent hot melt adhesive from overflowing to the uncoated edge area of ​​the coating film (30).

3. The coating film guiding mechanism of the dual hot melt coating machine according to claim 2, characterized in that, The edge support surface (15) of the arc-shaped support section transitions in an arc shape along the conveying direction of the coating film (30). The inlet end of the edge support surface (15) is lower than the middle support section. The outlet end of the edge support surface (15) corresponds to the guide height of the middle suspended guide film area (8), so that the uncoated edge area of ​​the coating film (30) forms a slightly arched guide state that transitions smoothly from low to high when passing through the edge support surface (15).

4. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, The adhesive guide beam (14) includes a beam body, a heat insulation cavity, and a removable anti-stick liner. The adhesive receiving groove (17) is formed on the side of the beam body facing the corresponding hot melt coating head. The heat insulation cavity is arranged along the length of the beam body between the adhesive receiving groove (17) and the guide film clearance surface (16). The removable anti-stick liner is laid in the adhesive receiving groove (17) to receive and isolate residual hot melt adhesive.

5. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, The adhesive separation switching assembly (9) includes a first follow-up trigger (18), a second follow-up trigger (19), a first switching swing arm (20), a second switching swing arm (21), and a reset elastic element (22). The first follow-up trigger (18) is connected to the lifting seat or swing seat of the first hot melt coating head (4), the second follow-up trigger (19) is connected to the lifting seat or swing seat of the second hot melt coating head (5), the first switching swing arm (20) is connected to the lateral flipping shaft (11) of the first linkage guide unit (6), the second switching swing arm (21) is connected to the lateral flipping shaft (11) of the second linkage guide unit (7), and the reset elastic element (22) is connected between the mounting frame (1) and the corresponding switching swing arm so that when the corresponding hot melt coating head returns to the coating position, the corresponding linkage guide unit can be reset from the adhesive separation position to the guide position.

6. The coating film guiding mechanism of the dual hot melt coating machine according to claim 5, characterized in that, A one-way clearance connection structure is provided between the first follower trigger (18) and the first switching arm (20), and between the second follower trigger (19) and the second switching arm (21). The one-way clearance connection structure includes an elongated hole connection part and a toggle pin disposed in the elongated hole connection part. When the corresponding hot melt coating head switches from the coating position to the clearance position, the toggle pin pushes the corresponding switching arm to rotate. When the corresponding hot melt coating head returns from the clearance position to the coating position, the corresponding switching arm is allowed to independently reset under the action of the reset elastic member (22).

7. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, The constant-length compensation linkage assembly (10) includes a first compensation wheel (23), a second compensation wheel (24), a cross drive belt (25), and a tension compensation wheel (26). The first compensation wheel (23) is coaxially connected to the lateral flip shaft (11) of the first linkage guide unit (6), and the second compensation wheel (24) is coaxially connected to the lateral flip shaft (11) of the second linkage guide unit (7). The cross drive belt (25) is wound between the first compensation wheel (23) and the second compensation wheel (24) to form a reverse linkage relationship between the first linkage guide unit (6) and the second linkage guide unit (7). The tension compensation wheel (26) is elastically pressed against the cross drive belt (25) to absorb the instantaneous membrane path length change generated when the first linkage guide unit (6) and the second linkage guide unit (7) switch.

8. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, The first edge guide arm (12) and the second edge guide arm (13) of the first linkage guide unit (6) and the second linkage guide unit (7) are both set on the corresponding horizontal flip axis (11) through the horizontal adjustment seat (27). The horizontal adjustment seat (27) can move and lock along the axial direction of the horizontal flip axis (11) to adjust the distance between the first edge guide arm (12) and the second edge guide arm (13) so that the edge film support surface (15) corresponds to the uncoated edge area of ​​the coating film (30) of different widths.

9. The coating film guiding mechanism of the dual hot melt coating machine according to claim 1, characterized in that, The mounting bracket (1) is also provided with a middle suspension limiter (28). The middle suspension limiter (28) is located between the first linkage guide unit (6) and the second linkage guide unit (7). The middle suspension limiter (28) includes two lateral limiters (29) arranged at intervals along the width direction of the coating film (30). The two lateral limiters (29) are respectively provided for the uncoated edge areas on both sides of the coating film (30). A middle adhesive-avoiding channel (31) is formed between the two lateral limiters (29) to allow the coating area of ​​the coating film (30) to pass through in the air.

10. A dual hot melt coating machine, characterized in that, The machine includes a machine base, a first hot melt coating head (4), a second hot melt coating head (5), and a coating film guiding mechanism for a dual hot melt coating machine as described in any one of claims 1 to 9. The coating film guiding mechanism includes a mounting frame (1), an infeed guide roller (2), an outfeed guide roller (3), a first linkage guiding unit (6), a second linkage guiding unit (7), a separation switching assembly (9), and a constant stroke compensation linkage assembly (10). The first hot melt coating head (4) and the second hot melt coating head (5) are arranged on the machine base along the conveying direction of the coating film (30). The infeed guide roller (2) The first hot melt coating head (4) is located on the film inlet side, and the film outlet guide roller (3) is located on the film outlet side of the second hot melt coating head (5). The first linkage guide unit (6) is linked to the first hot melt coating head (4), and the second linkage guide unit (7) is linked to the second hot melt coating head (5). This allows the coating film (30) to be suspended and guided by the uncoated edge areas on both sides during the double hot melt coating process, and ensures that the coating area of ​​the coating film (30) passes through the first hot melt coating head (4) and the second hot melt coating head (5) in a non-contact manner.

Images