Film conveying mechanism

Abstract

The invention discloses a thin film conveying mechanism, and relates to the technical field of mobile phone protective film production equipment, the thin film conveying mechanism comprises a buffer unit and a driving unit used for driving a thin film to move which are sequentially arranged in the moving direction of the thin film, and the thin film sequentially passes through the buffer unit and the driving unit; the buffering unit comprises a lower supporting plate and an upper supporting plate arranged above the lower supporting plate, the upper supporting plate and the lower supporting plate are vertically and movably connected, and lower rollers rotationally connected with the lower supporting plate are evenly distributed on the lower supporting plate in the moving direction of the film. Upper rollers rotationally connected with the upper supporting plate are evenly distributed on the upper supporting plate in the film moving direction, and a lifting assembly used for driving the upper supporting plate to move up and down is arranged on the lower supporting plate. When one film roll is used up, in the process of replacing a new film roll, the film wound on the upper roller and the lower roller in the buffer unit can temporarily support the operation of production in the process of replacing the film roll, so that the whole production line can keep continuous and stable operation.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile phone protective film production equipment, and particularly relates to a film conveying mechanism. Background Art

[0002] When producing mobile phone films, the raw material is a roll of film (commonly known as a film roll). The film on the film roll is released from the unwinding unit under the pulling of the driving unit and then sent to the subsequent blanking equipment for blanking.

[0003] When a film roll is used up, a new film roll needs to be replaced. During the replacement, the operation of the driving unit and the subsequent equipment needs to be paused, so the continuous operation of production cannot be guaranteed, thereby reducing production efficiency and affecting the production rhythm of products.

[0004] The patent with the publication number CN222410416U discloses a film conveying device with an anti-deviation function, which includes a bottom plate, a deviation detection component, a deviation correction component, a sliding table, a vertical plate, an adjustment component, and a lifting support component. The bottom plate is connected to the central control console, and two guiding rollers are symmetrically and rotatably arranged on the central control console. The deviation detection component is connected to the central control console. The deviation correction component is connected to the central control console and is located between the two guiding rollers on both sides. The sliding table is slidably connected to the bottom plate, and a linear module for driving the sliding table to slide is arranged on the bottom plate. The vertical plate is connected to one side of the sliding table, the vertical plate is rotatably connected to a support shaft, and two groups of clamping components are symmetrically arranged on the support shaft. The adjustment component is connected to the support shaft and is drivingly connected to the two groups of clamping components to adjust the distance between the two groups of clamping components. Since the film directly enters the central control console for deviation correction after being released, when the film is used up, the operation of the equipment needs to be interrupted to replace the new film roll, resulting in the inability to work continuously. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a film conveying mechanism to solve the problem that the driving unit and subsequent equipment need to be paused during the replacement of the film roll, thereby reducing production efficiency.

[0006] To solve the above technical problem, the technical solution adopted by the present invention is:

[0007] A film conveying mechanism includes a buffer unit and a driving unit for driving the film to move, which are arranged in sequence along the moving direction of the film. The film passes through the buffer unit and the driving unit in sequence. The buffer unit includes a lower support plate and an upper support plate arranged above the lower support plate. The upper support plate and the lower support plate are vertically movably connected. Along the moving direction of the film, lower rollers rotatably connected to the lower support plate are evenly distributed on the lower support plate. Along the moving direction of the film, upper rollers rotatably connected to the upper support plate are evenly distributed on the upper support plate. The axes of the upper rollers and the axes of the lower rollers are both perpendicular to the moving direction of the film in the horizontal plane. The film bypasses the lower rollers and the upper rollers in a serpentine shape. An elevating assembly for driving the upper support plate to move up and down is provided on the lower support plate.

[0008] Further, the elevating assembly includes a pair of upper connecting rods symmetrically arranged in a V shape and a pair of lower connecting rods symmetrically arranged in an inverted V shape. The two upper connecting rods and the two lower connecting rods correspond one by one. The two upper connecting rods and the two lower connecting rods are of equal length. The upper ends of the two upper connecting rods are respectively rotatably connected to the upper support plate. The lower ends of the two lower connecting rods are respectively rotatably connected to the lower support plate. The lower ends of the two upper connecting rods are respectively rotatably connected to the upper ends of the corresponding lower connecting rods. A synchronous driving structure for driving the two upper connecting rods to rotate synchronously and reversely and simultaneously driving the two lower connecting rods to rotate synchronously and reversely is provided on the upper support plate and the lower support plate.

[0009] Further, the synchronous driving structure includes an upper first gear fixedly connected to the upper end of one of the upper connecting rods, an upper second gear meshing with the upper first gear, an upper first sprocket coaxially and fixedly connected to the upper second gear, and an upper second sprocket fixedly connected to the upper end of the other upper connecting rod. The upper first gear, the upper second gear, the upper first sprocket, and the upper second sprocket are all rotatably connected to the upper support plate. The number of teeth of the upper first gear and the upper second gear is the same. The number of teeth of the upper first sprocket and the upper second sprocket is the same. An upper chain is wound around the upper first sprocket and the upper second sprocket.

[0010] Further, the synchronous driving structure includes a lower first gear fixedly connected to the lower end of one of the lower connecting rods, a lower second gear meshing with the lower first gear, a lower first sprocket coaxially and fixedly connected to the lower second gear, and a lower second sprocket fixedly connected to the lower end of the other lower connecting rod. The lower first gear, the lower second gear, the lower first sprocket, and the lower second sprocket are all rotatably connected to the lower support plate. The number of teeth of the lower first gear and the lower second gear is the same. The number of teeth of the lower first sprocket and the lower second sprocket is the same. A lower chain is wound around the lower first sprocket and the lower second sprocket.

[0011] Further, the synchronous driving structure includes a pulley rotatably connected to the middle of one of the lower connecting rods and a steel wire rope wound around the pulley. One end of the steel wire rope is tied to a position near the middle of the other lower connecting rod. The other end bypasses the pulley and hangs downwards with a counterweight at the lower end.

[0012] Further, the synchronous drive structure includes a tension spring disposed between two lower connecting rods. One end of the tension spring is hung on a pin in the middle of one of the lower connecting rods, and the other end is hung on a pin in the middle of the other lower connecting rod.

[0013] Further, it further includes a platform and a detection unit sequentially arranged on the film feeding side of the buffer unit from near to far. The film sequentially passes through the detection unit and the platform along its moving direction, and a film clamping unit for stopping the film from entering the buffer unit is provided on the platform.

[0014] Further, the detection unit includes a fixed U-shaped support frame and support rollers respectively rotatably connected to two top ends of the support frame. The film passes through the tops of the two support rollers. A swing arm rotatably connected to one end of the support frame is further provided on the support frame. The other end of the swing arm is rotatably connected to a movable roller. The movable roller is located between the two support rollers. The film passes through the bottom of the movable roller. A travel switch electrically connected to the film clamping unit is further provided in the support frame. After the movable roller drops, the swing arm triggers the travel switch.

[0015] Further, the film clamping unit includes a frame straddling both sides of the film in a gate shape. The frame is fixedly connected to the platform. A horizontal pressing plate is slidably connected in the frame. The film passes through the gap between the pressing plate and the platform. An electromagnetic push rod for driving the pressing plate to move up and down is fixedly connected to the frame.

[0016] The positive effects of the present invention are as follows:

[0017] The present invention is provided with a buffer unit. The buffer unit includes a lower support plate and an upper support plate. The upper support plate is provided with upper rollers, and the lower support plate is provided with lower rollers. The film winds around the upper rollers and the lower rollers in a snake shape. When one film roll is used up, during the process of replacing the new film roll, the film wound around the upper rollers and the lower rollers in the buffer unit can temporarily support the production operation during the film roll replacement process, so that the entire production line can maintain continuous and stable operation. The buffer unit adopts a pure mechanical structure, and there is no need to be equipped with an electrical control system when replacing the film roll, and the reliability is higher. Description of the Drawings

[0018] Figure 1 is the system diagram of Embodiments 1, 2, 4, and 5;

[0019] Figure 2 is the structural schematic diagram of the buffer unit in Embodiments 1, 2, 4, and 5;

[0020] Figure 3 is the structural schematic diagram of the buffer unit in Embodiment 3;

[0021] Figure 4It is a schematic structural diagram of a detection unit, a film receiving unit, and a film clamping unit;

[0022] In the figure:

[0023] 1. Detection unit; 2. Film receiving unit; 3. Platform; 4. Film clamping unit; 5. Buffer unit; 6. Driving unit; 7. Film; 8. Lower roller; 9. Pulley; 10. Lower connecting rod; 11. Upper connecting rod; 12. Upper roller; 13. Upper first gear; 14. Upper second gear; 15. Upper first sprocket; 16. Upper chain; 17. Upper second sprocket; 18. Lower second sprocket; 19. Lower chain; 20. Lower first sprocket; 21. Lower second gear; 22. Counterweight; 23. Steel wire rope; 24. Lower first gear; 25. Tension spring; 26. Pin; 27. Threaded hole; 28. Electromagnetic push rod; 29. Frame; 30. Pressure plate; 31. Movable roller; 32. Support roller; 33. Support frame; 34. Swing arm; 35. Travel switch; 36. Unwinding unit; 37. Upper support plate; 38. Lower support plate. Specific implementation manner

[0024] Embodiment 1

[0025] As Figure 1 and Figure 2 shown, the film roll is placed on the unwinding unit 36, and the film 7 unwound from the unwinding unit 36 moves from left to right under the pulling of the driving unit 6. The driving unit 6 mainly consists of a bracket installed on the ground and two rotatable drums, an upper one and a lower one, rotatably connected inside the bracket. The two drums are driven by a motor to rotate in opposite directions, thereby pulling the film 7 clamped between the two drums to the right. This structure is prior art and will not be elaborated here.

[0026] A film conveying mechanism includes a buffer unit arranged between the unwinding unit 36 and the driving unit 6. After the film 7 is unwound from the unwinding unit 36, it passes through the buffer unit 5 and the driving unit 6 in sequence from right to left. The buffer unit 5 includes a long strip-shaped lower support plate 38 and a long strip-shaped upper support plate 37 arranged parallel to the lower support plate 38 directly above it. Both the upper support plate 37 and the lower support plate 38 are arranged in the horizontal direction. Legs are welded to the bottom of the lower support plate 38, and the legs support on the ground.

[0027] The upper support plate 37 and the lower support plate 38 are vertically movably connected. Five lower rollers 8 are evenly distributed from left to right on the lower support plate 38 and are rotatably connected to the lower support plate 38. Four upper rollers 12 are evenly distributed from left to right on the upper support plate 37 and are rotatably connected to the upper support plate 37. The four upper rollers 12 and the five lower rollers 8 are staggered in the horizontal direction. The axis of the upper roller 12 and the axis of the lower roller 8 are both perpendicular to the moving direction of the film 7 in the horizontal plane. After entering from the bottom of the lower roller 8 on the left, the film 7 snakes around the lower rollers 8 and the upper rollers 12, and then goes out from the lower roller 8 on the right. The lower support plate 38 is provided with a lifting component for driving the upper support plate 37 to move up and down.

[0028] The lifting assembly includes a pair of upper connecting rods 11 symmetrically arranged in an eight-shaped shape and a pair of lower connecting rods 10 symmetrically arranged in an inverted eight-shaped shape. The two upper connecting rods 11 and the two lower connecting rods 10 correspond one to one vertically, and the two upper connecting rods 11 and the two lower connecting rods 10 are equal in length. The upper ends of the two upper connecting rods 11 are rotatably connected to the left and right ends of the upper support plate 37 respectively, and the lower ends of the two lower connecting rods 10 are rotatably connected to the parts of the lower support plate 38 close to the left and right ends respectively. The lower ends of the two upper connecting rods 11 are hinged to the upper ends of the corresponding lower connecting rods 10 respectively, and the upper support plate 37 and the lower support plate 38 are provided with a synchronous driving structure for driving the two upper connecting rods 11 to rotate synchronously in the opposite direction and driving the two lower connecting rods 10 to rotate synchronously in the opposite direction.

[0029] The working process of the present invention is:

[0030] When a film roll is used up, the film 7 on the left side of the buffer unit 5 stops moving. At this time, the drive unit 6 continues to run and pulls the film 7 on the right side of the buffer unit 5 to the right. Under the pull of the film 7 and the drive of the synchronous drive structure, the two upper connecting rods 11 and the two lower connecting rods 10 are synchronously opened outward, so that the upper support plate 37 moves vertically downward to ensure that the film 7 is continuously output from the right side of the buffer unit 5. At the same time, a new film roll is replaced, and the film 7 on the new film roll is connected to the previous film. After the connection is completed, the synchronous drive structure drives the two upper connecting rods 11 and the two lower connecting rods 10 to retract inward synchronously, so that the upper support plate 37 rises to increase the length of the film 7 inside the buffer unit 5.

[0031] Therefore, when a film roll is used up and a new film roll is replaced, the film 7 in the buffer unit 5 can temporarily support the production operation during the film roll replacement process, so that the entire production line can maintain continuous and stable operation, and the products produced at the joint of the films 7 of the two film rolls can be treated as waste.

[0032] Example 2

[0033] The difference between this embodiment and Embodiment 1 lies in that: the synchronous drive structure includes an upper first gear 13 fixedly connected to the upper end of the left upper connecting rod 11, an upper second gear 14 meshing with the upper first gear 13, an upper first sprocket 15 coaxially and fixedly connected to the upper second gear 14, and an upper second sprocket 17 fixedly connected to the upper end of the right upper connecting rod 11. The upper first gear 13, the upper second gear 14, the upper first sprocket 15, and the upper second sprocket 17 are all rotatably connected to the upper support plate 37. The number of teeth of the upper first gear 13 and the upper second gear 14 is the same, the number of teeth of the upper first sprocket 15 and the upper second sprocket 17 is the same, and an upper chain 16 is wound around the upper first sprocket 15 and the upper second sprocket 17.

[0034] The synchronous drive structure further includes a lower first gear 24 fixedly connected to the lower end of the left lower connecting rod 10, a lower second gear 21 meshing with the lower first gear 24, a lower first sprocket 20 coaxially and fixedly connected to the lower second gear 21, and a lower second sprocket 18 fixedly connected to the lower end of the right lower connecting rod 10. The lower first gear 24, the lower second gear 21, the lower first sprocket 20, and the lower second sprocket 18 are all rotatably connected to the lower support plate 38. The number of teeth of the lower first gear 24 and the lower second gear 21 is the same, the number of teeth of the lower first sprocket 20 and the lower second sprocket 18 is the same, and a lower chain 19 is wound around the lower first sprocket 20 and the lower second sprocket 18.

[0035] When the upper end of one of the lower connecting rods 10 swings outward, the lower first gear 24 rotates counterclockwise, driving the lower second gear 21 to rotate clockwise, and at the same time driving the lower first sprocket 20 to rotate clockwise, and then driving the lower second sprocket 18 to rotate clockwise through the lower chain 19. Since the number of teeth of the lower first gear 24 and the lower second gear 21 is the same, and the number of teeth of the lower first sprocket 20 and the lower second sprocket 18 is the same, the two lower connecting rods 10 swing outward synchronously.

[0036] When the two lower connecting rods 10 swing outward synchronously, they drive the lower ends of the two upper connecting rods 11 to swing outward synchronously. Under the action of the upper first gear 13, the upper second gear 14, the upper first sprocket 15, the upper second sprocket 17, and the upper chain 16, when the two upper connecting rods 11 swing synchronously, they drive the upper support plate 37 to move downward vertically, and at the same time, the upper support plate 37 can be kept horizontal, avoiding the adjacent films 7 between the upper roller 12 and the lower roller 8 from rubbing against each other due to the left and right movement of the upper support plate 37 after it descends, or affecting the operation of adjacent equipment. Therefore, since the upper support plate 37 moves vertically up and down, the space occupied by the buffer unit 5 is smaller.

[0037] The length of the thin film 7 in the buffer unit 5 can be achieved by adjusting the lengths of the upper connecting rod 11 and the lower connecting rod 10 or by adjusting the numbers of the upper roller 12 and the lower roller 8. The two upper connecting rods 11 are connected to both ends of the upper support plate 37, and the two lower connecting rods 10 are connected to the parts of the lower support plate 38 near both ends, so that the upper support plate 37 moves more smoothly up and down.

[0038] Embodiment 3

[0039] The difference between this embodiment and Embodiment 2 is that:

[0040] The synchronous drive structure further includes a pulley 9 rotatably connected to the middle parts of the two lower connecting rods 10 and two steel wire ropes 23 respectively wound around each pulley 9. One end of each steel wire rope 23 is tied to the part of the lower connecting rod 10 near the middle, and the other end hangs down after passing around the pulley 9 on the other lower connecting rod 10 and is hung with a counterweight 22 at the lower end.

[0041] Through the cooperation of the counterweight 22, the steel wire rope 23 and the pulley 9, an inward pulling force can be applied to the two lower connecting rods 10, so that the thin film 7 between the upper roller 12 and the lower roller 8 is kept taut. When replacing a new film roll, the thin film 7 on the left side of the buffer unit 5 stops entering, and the driving unit 6 continues to pull the thin film 7 to the right. The pulling force of the driving unit 6 can overcome the pulling force of the counterweight 22 acting on the thin film 7, and the thin film 7 in the buffer unit 5 continues to be sent out to the right, thereby pulling the upper support plate 37 to move downward, and then pulling the steel wire rope 23 to make the counterweight 22 rise, so as to store gravitational potential energy.

[0042] After replacing the new film roll, under the action of the pulling force of the driving unit 6, the thin film 7 on the left side of the buffer unit 5 continues to be fed in, the counterweight 22 moves downward, pulls the steel wire rope 23, and drives the upper support plate 37 to move upward through the two lower connecting rods 10 and the two upper connecting rods 11 to increase the length of the thin film 7 between the upper roller 12 and the lower roller 8. Until the part of the lower connecting rod 10 near the lower end abuts against the limit pin welded on the lower support plate 38, the counterweight 22 stops descending, and the upper support plate 37 reaches the highest position at this time.

[0043] Therefore, in this embodiment, when replacing the film roll, a pure mechanical structure is adopted to automatically provide continuous thin film 7 to the subsequent production equipment without equipping an electrical control system, and the reliability is higher.

[0044] Embodiment 4

[0045] Combined with Figure 3 As shown, the difference between this embodiment and Embodiment 2 is that:

[0046] The synchronous drive structure further includes a tension spring 25 disposed horizontally between the two lower connecting rods 10. One end of the tension spring 25 is hung on a pin 26 in the middle of one of the lower connecting rods 10, and the other end is hung on the pin 26 in the middle of the other lower connecting rod 10. Four threaded holes 27 are provided along the length direction on each lower connecting rod 10, and one end of the pin 26 is screwed into one of the threaded holes 27.

[0047] When replacing the new film roll, the film 7 on the left side of the buffer unit 5 stops entering, and the driving unit 6 continues to pull the film 7 to the right. The pulling force of the driving unit 6 can overcome the pulling force of the tension spring 25, and the film 7 in the buffer unit 5 continues to be sent out to the right, thereby pulling the upper support plate 37 downward, and further stretching the tension spring 25, so as to store elastic potential energy.

[0048] After replacing the new film roll, under the action of the pulling force of the driving unit 6, the film 7 on the left side of the buffer unit 5 continues to be fed in, and the tension spring 25 pulls the two lower connecting rods 10 inward, driving the upper support plate 37 to move upward through the two upper connecting rods 11 to increase the length of the film 7 between the upper roller 12 and the lower roller 8. Until the part of the lower connecting rod 10 near the lower end abuts against the limit pin welded on the lower support plate 38, the lower connecting rod 10 stops rotating, and the upper support plate 37 reaches the highest position at this time.

[0049] Therefore, in this embodiment, when replacing the film roll, a pure mechanical structure is adopted to automatically provide continuous film 7 to subsequent production equipment without the need to be equipped with an electrical control system, so the reliability is higher. In addition, when the upper support plate 37 moves from top to bottom, the acute angle between the two lower connecting rods 10 and the horizontal direction gradually decreases, so the component of the pulling force of the tension spring 25 acting on the two lower connecting rods 10 in the vertical upward direction on the upper support plate 37 gradually decreases. As the tension spring 25 elongates, the pulling force acting on the two lower connecting rods 10 gradually increases, so that the upward thrust of the tension spring 25 acting on the upper support plate 37 through the two lower connecting rods 10 and the two upper connecting rods 11 changes little, so that the pulling force on the film 7 between the upper roller 12 and the lower roller 8 changes little, so that the tension received by the film 7 during movement and transmission is more stable.

[0050] Embodiment 5

[0051] Combined with Figure 4 As shown, a platform 3 and a detection unit 1 are sequentially arranged from right to left on the film inlet side of the buffer unit 5. Columns are provided on the ground of the platform 3, and the columns are fixed on the ground. The film 7 passes through the detection unit 1 and the upper surface of the platform 3 from left to right, and a film clamping unit 4 for stopping the film 7 from entering the buffer unit 5 is provided on the platform 3.

[0052] The detection unit 1 includes a U-shaped support frame 33 and support rollers 32 respectively rotatably connected to two top ends of the support frame 33. A support column is fixedly connected to the lower part of the shown support frame 33, and the shown support column is fixed on the ground. The film 7 passes over the tops of the two support rollers 32. A swing arm 34 is rotatably connected to one end of the support frame 33. The other end of the swing arm 34 is rotatably connected to a movable roller 31. The movable roller 31 is located between the two support rollers 32. The film 7 passes under the movable roller 31.

[0053] The film clamping unit 4 includes a frame 29 straddling the front and rear sides of the film 7 in a gate shape. The frame 29 is fixedly connected to the platform 3. A horizontal pressing plate 30 is vertically slidably connected inside the frame 29. The film 7 passes through the gap between the pressing plate 30 and the platform 3. An electromagnetic push rod 28 is fixedly connected to the top of the frame 29. The push rod of the electromagnetic push rod 28 faces downward and is fixedly connected to the pressing plate 30 for driving the pressing plate 30 to move up and down.

[0054] A travel switch 35 is fixedly connected to the inner side of the support frame 33. The travel switch 35 is connected to a controller, and the electromagnetic push rod 28 is electrically connected to the controller. When all the film 7 on the film roll is released and the film 7 disengages from the unwinding unit 36, since the tension at the left end of the film 7 passing through the detection unit 1 disappears and it cannot be tightened, the movable roller 31 sags under the action of gravity, driving the swing arm 34 to rotate, triggering the travel switch 35. The controller controls the electromagnetic push rod 28 to act, clamping the film 7 downward, thereby preventing the film 7 on the left side of the buffer unit 5 from moving, and at the same time emitting an audible and visual alarm to prompt the operator to replace the film roll.

[0055] A film receiving unit 2 is further provided on the platform 3 on the left side of the film clamping unit 4. The film receiving unit 2 can be a heat sealer or an ultrasonic welding machine. After installing a new film roll on the unwinding unit 36, lift the movable roller 31 upward to make the film 7 of this film roll pass through the two support rollers 32, cut the end of the film 7 neatly, then weld the end of the film 7 of the new film roll to the end of the previous film 7, lower the movable roller 31 and press it on the film 7, and then press the reset button on the controller. The electromagnetic push rod 28 resets, the pressing plate 30 moves upward, and the film 7 is released. The heat sealer and the ultrasonic welding machine are both prior arts, and their structures and operation methods will not be elaborated here.

[0056] Through the detection unit 1 and the film clamping unit 4, the film 7 can be automatically clamped after it is released, thereby preventing the film 7 from being pulled into the buffer unit 5 and making it difficult to connect the film 7 of the new film roll to the previous film 7.

[0057] To further ensure the stability of the buffer unit 5, there are two upper support plates 37 provided on the front and rear sides of the upper roller 12, and two lower support plates 37 provided on the front and rear sides of the lower roller 8. Correspondingly, there are two sets of lifting assemblies provided on the front and rear sides of the upper roller 12 and the lower roller 8.

[0058] The above embodiments are described in more detail and specifically, expressing the preferred embodiments of the present invention. They are only used to illustrate the technical ideas and features of the present invention. The purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. However, it is not limited to the present invention only. The patent scope of the present invention cannot be limited only by this embodiment. That is, any equivalent changes or modifications made in accordance with the spirit disclosed by the present invention, for researchers or technicians in the field, within the structure of the present invention, local improvements within the system and changes and transformations between subsystems are still within the patent scope of the present invention.

Claims

1. A film conveying mechanism, characterized in that: The invention comprises a buffer unit (5) arranged in sequence along the moving direction of the film (7) and a driving unit (6) for driving the film (7) to move, wherein the film (7) passes through the buffer unit (5) and the driving unit (6) in sequence; the buffer unit (5) comprises a lower support plate (38) and an upper support plate (37) arranged above the lower support plate (38), wherein the upper support plate (37) and the lower support plate (38) are vertically movably connected, and the lower support plate (38) is uniformly provided with a plurality of support plates which are arranged along the moving direction of the film (7) and are connected to the lower support plate (38). The support plate (38) is rotatably connected to a lower roller (8), and upper rollers (12) rotatably connected to the upper support plate (37) are evenly distributed on the upper support plate (37) along the moving direction of the film (7). The axis of the upper roller (12) and the axis of the lower roller (8) are both perpendicular to the moving direction of the film (7) in a horizontal plane. The film (7) snakes around the lower roller (8) and the upper roller (12). The lower support plate (38) is provided with a lifting component for driving the upper support plate (37) to move up and down.

2. A film conveying mechanism according to claim 1, characterized in that: The lifting assembly comprises a pair of upper connecting rods (11) symmetrically arranged in an eight-shaped shape and a pair of lower connecting rods (10) symmetrically arranged in an inverted eight-shaped shape, the two upper connecting rods (11) and the two lower connecting rods (10) correspond to each other one by one, the two upper connecting rods (11) and the two lower connecting rods (10) are of equal length, the upper ends of the two upper connecting rods (11) are respectively rotatably connected to the upper support plate (37), the lower ends of the two lower connecting rods (10) are respectively rotatably connected to the lower support plate (38), the lower ends of the two upper connecting rods (11) are respectively rotatably connected to the upper ends of the corresponding lower connecting rods (10), and the upper support plate (37) and the lower support plate (38) are provided with a synchronous driving structure for driving the two upper connecting rods (11) to rotate synchronously in the opposite direction and driving the two lower connecting rods (10) to rotate synchronously in the opposite direction.

3. A film conveying mechanism according to claim 2, characterized in that: The synchronous drive structure comprises an upper first gear (13) fixedly connected to the upper end of one of the upper connecting rods (11), an upper second gear (14) meshing with the upper first gear (13), an upper first sprocket (15) coaxial with and fixedly connected to the upper second gear (14), and an upper second sprocket (17) fixedly connected to the upper end of the other upper connecting rod (11); the upper first gear (13), the upper second gear (14), the upper first sprocket (15) and the upper second sprocket (17) are all rotatably connected to the upper support plate (37); the upper first gear (13) and the upper second gear (14) have the same number of teeth; the upper first sprocket (15) and the upper second sprocket (17) have the same number of teeth; and an upper chain (16) is wound around the upper first sprocket (15) and the upper second sprocket (17).

4. A film conveying mechanism according to claim 3, characterized in that: The synchronous drive structure comprises a lower first gear (24) fixedly connected to the lower end of one of the lower connecting rods (10), a lower second gear (21) meshing with the lower first gear (24), a lower first sprocket (20) coaxial with and fixedly connected to the lower second gear (21), and a lower second sprocket (18) fixedly connected to the lower end of the other lower connecting rod (10); the lower first gear (24), the lower second gear (21), the lower first sprocket (20) and the lower second sprocket (18) are all rotatably connected to the lower support plate (38); the lower first gear (24) and the lower second gear (21) have the same number of teeth; the lower first sprocket (20) and the lower second sprocket (18) have the same number of teeth; and a lower chain (19) is wound around the lower first sprocket (20) and the lower second sprocket (18).

5. A film conveying mechanism according to any one of claims 2 to 4, characterized in that: The synchronous drive structure comprises a pulley (9) rotatably connected to the middle part of one of the lower connecting rods (10) and a steel wire rope (23) wound around the pulley (9); one end of the steel wire rope (23) is tied to a portion near the middle part of the other lower connecting rod (10), and the other end of the steel wire rope (23) is passed around the pulley (9) and then hangs down, with a counterweight (22) hung at the lower end.

6. A film conveying mechanism according to any one of claims 2 to 4, characterized in that: The synchronous drive structure comprises a tension spring (25) arranged between two lower connecting rods (10), one end of the tension spring (25) being hung on a pin (26) in the middle of one of the lower connecting rods (10), and the other end being hung on a pin (26) in the middle of the other lower connecting rod (10).

7. A film conveying mechanism according to claim 1, characterized in that: The device also comprises a platform (3) and a detection unit (1) which are arranged in sequence from near to far on the film inlet side of the buffer unit (5); the film (7) passes through the detection unit (1) and the platform (3) in sequence along its moving direction; and a film clamping unit (4) is provided on the platform (3) for stopping the film (7) from entering the buffer unit (5).

8. A film conveying mechanism according to claim 7, characterized in that: The detection unit (1) comprises a fixed U-shaped support frame (33) and two support rollers (32) rotatably connected to the top ends of the support frame (33), the film (7) passes through the tops of the two support rollers (32), the support frame (33) is also provided with a swing arm (34) with one end rotatably connected thereto, the other end of the swing arm (34) is rotatably connected to a movable roller (31), the movable roller (31) is located between the two support rollers (32), the film (7) passes through the bottom of the movable roller (31), the support frame (33) is also provided with a travel switch (35) electrically connected to the film clamping unit (4), and after the movable roller (31) falls, the swing arm (34) triggers the travel switch (35).

9. A film conveying mechanism according to claim 7, characterized in that: The film clamping unit (4) comprises a door-shaped frame (29) spanning both sides of the film (7); the frame (29) is fixedly connected to the platform (3); a horizontal pressing plate (30) is slidably connected inside the frame (29); the film (7) passes through the gap between the pressing plate (30) and the platform (3); and an electromagnetic push rod (28) is fixedly connected to the frame (29) for driving the pressing plate (30) to move up and down.

Images