Battery cell fixing jig

Abstract

The utility model relates to the technical field of jigs, and discloses a battery cell fixing jig, which comprises a fixing base for bearing a battery cell; the pressing block is rotationally mounted on one side of the top of the fixed base; the first driving assembly comprises a first crank arm and a first driving device arranged on one side of the bottom of the fixed base, one end of the first crank arm is hinged to the pressing block, and the other end of the first crank arm is hinged to the driving end of the first driving device; and the first driving device drives the first crank arm to move, so that the pressing block rotates and tightly presses the battery cell. According to the battery cell fixing jig disclosed by the utility model, the occupied area of other parts on the top surface of the fixing base can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of jigs, in particular to a battery core fixing jig. Background Art

[0002] During the battery cell production process, it is often necessary to fix the battery cells before connecting or assembling other components to the battery cells. Generally, a jig is used to fix the battery cells. The jig generally includes a fixed base and a clamping assembly installed on the fixed base. The clamping assemblies are all arranged on the top surface of the fixed base, occupying a large area of ​​the top surface of the fixed base, resulting in a larger size of the jig, and the clamping assembly easily blocks the robot from placing or removing the battery cells.

[0003] In view of this, it is necessary to design a battery cell fixing fixture to reduce the area occupied by other components on the top surface. Utility Model Content

[0004] The utility model aims to provide a battery core fixing fixture to reduce the area occupied by other components on the top surface.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A battery cell fixing fixture, comprising:

[0007] A fixed base for carrying the battery cells;

[0008] A pressing block, rotatably mounted on one side of the top of the fixed base;

[0009] A first driving assembly, comprising a first curved arm and a first driving device disposed on one side of the bottom of the fixed base, wherein one end of the first curved arm is hinged to the pressing block, and the other end is hinged to the driving end of the first driving device;

[0010] The first driving device drives the first crank arm to move so that the pressing block rotates and presses the battery core.

[0011] Optionally, a fixing seat is provided on a side of the fixing base, and the pressing block is rotatably mounted on the fixing seat via a first rotating shaft.

[0012] Optionally, the pressing block and the first rotating shaft are an integral structure, or the fixing seat and the first rotating shaft are an integral structure.

[0013] Optionally, the pressing block is rotatably mounted on the fixed base via a first rotating shaft, one end of the first curved arm is rotatably connected to the end of the pressing block via a second rotating shaft, and the other end is rotatably connected to the driving end of the first driving device via a third rotating shaft, the first rotating shaft, the second rotating shaft and the third rotating shaft are parallel to each other, and the moving direction of the driving end of the first driving device is perpendicular to the third rotating shaft.

[0014] Optionally, one end of the first curved arm is hinged to the pressing block ball, and the other end is hinged to the driving end ball.

[0015] Optionally, at least two pressing blocks are provided, and the two pressing blocks are respectively provided on two opposite sides of the fixed base;

[0016] Alternatively, a positioning vertical plate for stopping the battery core is further provided on the fixed base, and the positioning vertical plate and the pressing block are arranged opposite to each other.

[0017] Optionally, the pressing block is provided with a pressing portion for pressing the battery cell, and the first rotating shaft is located between the second rotating shaft and the pressing portion.

[0018] Optionally, a supporting pad is provided on the fixed base;

[0019] The opposite side edges of the support pad are both provided with avoidance grooves for avoiding the clamping claws.

[0020] Optionally, the battery cell fixing jig further includes a film pressing device for pressing the insulating film;

[0021] The film pressing device comprises a support seat mounted on the fixed base, a film pressing assembly rotatably mounted on the support seat to press the insulating film, and a second driving assembly for driving the film pressing assembly to rotate;

[0022] The film pressing assembly includes a film pressing plate rotatably mounted on the support seat and a film pressing roller rotatably mounted on the film pressing plate; the second driving assembly is used to drive the film pressing assembly to rotate relative to the support seat so that the film pressing roller presses the insulating film.

[0023] Optionally, the second driving assembly includes a second curved arm and a second linear driving device, one end of the second curved arm is rotatably connected to the end of the film pressing assembly, and the other end is rotatably connected to the driving end of the second linear driving device.

[0024] Optionally, the first driving device comprises a connecting plate and a driving cylinder, and a driving shaft of the driving cylinder is perpendicular to the third rotating shaft;

[0025] A resetting elastic member is also installed between the fixed base and the connecting plate. When the driving cylinder stops driving, the resetting elastic member is reset to allow the pressing block to keep pressing the battery core.

[0026] Optionally, the battery cell fixing fixture further comprises a side clamping block, and the side clamping block is fixedly connected to the adjacent connecting plate;

[0027] When the pressing block presses the battery core, the side clamping block contacts the side surface of the battery core.

[0028] Optionally, the battery cell fixing fixture further includes a top cover positioning assembly arranged on one side of the fixing base;

[0029] The top cover positioning assembly comprises a support plate and a positioning assembly, wherein the positioning assembly and the support plate form a positioning station for placing the top cover;

[0030] The positioning assembly includes at least two positioning blocks arranged opposite to each other and at least two positioning columns arranged opposite to each other;

[0031] When the battery cell is placed in the positioning station, one side surface of the battery cell at least abuts against one positioning block or at least abuts against one positioning column.

[0032] Compared with the prior art, the utility model has the following beneficial effects:

[0033] In this embodiment, through a clever structural arrangement, the first execution drive device at the bottom can drive the pressing block to rotate through the crank arm, so that the pressing block can press or loosen the battery cell; part of the structure in this embodiment is located on the bottom side of the fixed base, which can effectively reduce the area occupied by other components on the top surface of the fixed base, and can better plan the movement path of the manipulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.

[0036] Figure 1 A schematic diagram of the three-dimensional structure of a battery cell fixing fixture provided in an embodiment of the utility model;

[0037] Figure 2 A schematic diagram of the three-dimensional structure of the battery cell fixing fixture provided by an embodiment of the utility model when viewed from another perspective;

[0038] Figure 3 for Figure 2 A magnified schematic diagram of position A in the middle;

[0039] Figure 4 A schematic diagram of the top view of the battery cell fixing fixture provided in an embodiment of the utility model;

[0040] Figure 5 for Figure 4 Schematic diagram of the AA section structure;

[0041] Figure 6 for Figure 4 Schematic diagram of the structure of the middle BB section;

[0042] Figure 7 A bottom view schematic diagram of a battery cell fixing fixture provided by an embodiment of the utility model;

[0043] Figure 8 A partially enlarged schematic diagram of a battery cell fixing fixture provided by an embodiment of the utility model when viewed from above;

[0044] Fig. 9 A three-dimensional schematic diagram of a support pad provided in an embodiment of the utility model;

[0045] Fig.10 A three-dimensional schematic diagram of a top cover positioning assembly provided in an embodiment of the utility model.

[0046] Illustrations: 1. Fixed base; 11. First rotating shaft; 12. Second rotating shaft; 13. Third rotating shaft; 201. Elastic buffer layer; 21. Fixed seat; 22. Pressing block; 23. First driving assembly; 231. First curved arm; 232. Connecting plate; 233. Resetting elastic member; 3. Support pad; 301. Avoidance groove; 4. Film pressing device; 41. Support seat; 42. Film pressing assembly; 421. Film pressing plate; 422. Film pressing roller; 43. Second driving assembly; 4301. Rotary driving device; 4302. Flange; 4303. Connecting curved arm; 4304. Sliding part; 431. Second curved arm; 51. First film pressing shaft; 52. Second film pressing shaft; 53. Third film pressing shaft; 6. Side clamping block; 7. Slide rail; 8. Top cover positioning assembly; 81. Support plate; 82. Positioning block; 83. Positioning column. DETAILED DESCRIPTION

[0047] In order to make the utility model's purpose, features, and advantages more obvious and easy to understand, the following will be combined with the drawings in the utility model embodiments to clearly and completely describe the technical solutions in the utility model embodiments. Obviously, the embodiments described below are only part of the utility model embodiments, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0048] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0049] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0050] Embodiment 1

[0051] The embodiment of the utility model provides a battery core fixing fixture, which can reduce the area occupied by other components on the top surface of the fixing base 1 and reduce the possibility of other components blocking the robot arm.

[0052] See also Figures 1 to 9 The battery cell fixing fixture includes a fixing base 1 and a pressing block 22 , a first driving assembly 23 and a first curved arm 231 .

[0053] Among them, the fixed base 1 is used to carry the battery cell; the pressing block 22 is rotatably installed on the top side of the fixed base 1; the first driving assembly 23 includes a first curved arm 231 and a first driving device arranged on the bottom side of the fixed base 1, one end of the first curved arm 231 is hinged to the pressing block 22, and the other end is hinged to the driving end of the first driving device; the first driving device drives the first curved arm 231 to move, so that the pressing block 22 rotates and presses the battery cell.

[0054] In the actual work process, Figure 5, the first driving device drives the bottom end of the first curved arm 231 to move, thereby driving the pressing block 22 to rotate, and the pressing block 22 rotates to a suitable angle to clamp the battery cell on the fixed base 1. Preferably, the first driving device can be a cylinder, an electric telescopic device or other driving device. When it is not necessary to clamp the battery cell, the first driving device drives in the reverse direction, so that the pressing block 22 releases the battery cell.

[0055] Optionally, a fixing seat 21 is provided on the side of the fixing base 1, and the pressing block 22 is rotatably mounted on the fixing seat 21 via the first rotating shaft 11. The fixing seat 21 supports the pressing block 22, so that the pressing block 22 is at the top of the fixing base 1, so that the pressing block 22 can more easily press the battery cell, that is, the rotation angle of the pressing block 22 does not need to be too large to press the battery cell. The pressing block 22 is rotatably connected to the fixing seat 21 via the first rotating shaft 11.

[0056] Preferably, the pressing block 22 and the first rotating shaft 11 are an integral structure, or the fixing seat 21 and the first rotating shaft 11 are an integral structure.

[0057] Optionally, the pressing block 22 is rotatably mounted on the fixed base 1 via a first rotating shaft 11, one end of the first curved arm 231 is rotatably connected to the end of the pressing block 22 via a second rotating shaft 12, and the other end is rotatably connected to the driving end of the first driving device via a third rotating shaft 13, the first rotating shaft 11, the second rotating shaft 12 and the third rotating shaft 13 are parallel to each other, and the moving direction of the driving end of the first driving device is perpendicular to the third rotating shaft.

[0058] It should be noted that the second rotating shaft 12 and the pressing block 22 may be an integral structure, or the first crank arm 231 and the second rotating shaft 12 may be an integral structure, or the second rotating shaft 12, the first crank arm 231, and the pressing block 22 may be three components.

[0059] The first rotating shaft 11, the second rotating shaft 12 and the third rotating shaft 13 are parallel to each other, which is conducive to smoother rotation, more reasonable structure, and convenient transmission of the force for pressing the battery cell, so that the pressure of the pressing block 22 on the battery cell is greater.

[0060] In another specific embodiment, one end of the first curved arm 231 is ball-jointed to the pressing block 22 , and the other end is ball-jointed to the driving end.

[0061] In this embodiment, only the pressing block 22 is located on the top side of the fixed base 1, and the pressing block 22 occupies a smaller area of ​​the top surface, thereby helping to reduce the overall volume of the battery cell fixing fixture. Compared with the existing clamping assembly, in the structure of this embodiment, the part located on the top side of the fixed base 1 is less likely to block the manipulator, thereby making the path for the manipulator to grab the battery cell more reasonable.

[0062] It should be noted that the first driving device can be a cylinder, a motor screw assembly, an electric telescopic rod, a linear module, etc. For example, when the first driving device is a cylinder, the cylinder body of the cylinder is hinged to the fixed base 1, the telescopic rod of the cylinder is rotatably connected to the first crank arm 231 through the third rotating shaft 13, and the telescopic rod of the cylinder is perpendicular to the third rotating shaft 13; of course, the telescopic rod of the cylinder can be parallel to the top surface of the fixed base 1, and can also form an angle with the top surface of the fixed base 1.

[0063] Optionally, at least two pressing blocks 22 are provided, and the two pressing blocks 22 are arranged on opposite sides of the fixed base 1 ; the two pressing blocks 22 act synchronously from both sides of the battery cell, thereby pressing the battery cell against the top surface of the fixed base 1 . Figure 5 The first driving device is used to open the pressing block 22 and press the battery cell onto the fixed base 1. Preferably, at least two pressing blocks 22 are arranged on the same side of the fixed base 1 to improve the fixing effect on the battery cell.

[0064] In another specific embodiment, a positioning vertical plate for stopping the battery cell is further provided on the fixed base 1, and the positioning vertical plate and the pressing block 22 are arranged opposite to each other. That is, after the positioning vertical plate stops and positions the battery cell, the pressing block 22 presses the battery cell onto the fixed base 1.

[0065] Optionally, the pressing block 22 is provided with a pressing portion for pressing the battery cell, and the first rotating shaft 11 is located between the second rotating shaft 12 and the pressing portion, so that the first curved arm 231 can better drive the pressing block 22 to rotate around the first rotating shaft 11 .

[0066] Optionally, an elastic buffer layer 201 is provided on the pressing portion, and the elastic buffer layer 201 is provided on the bottom side of the pressing portion close to the fixed base 1. The provision of the elastic buffer layer 201 can reduce the possibility of failure to compress the battery cell due to the thickness deviation of the battery cell, and can effectively avoid embossing the side of the battery cell.

[0067] Optionally, a support pad 3 is provided on the fixed base 1; and avoidance grooves 301 for avoiding the clamping claws are provided on the opposite side edges of the support pad 3. Specifically, the provision of the support pad 3 can reduce the possibility of collision between the manipulator and the fixed base 1 when clamping and placing or clamping the battery cell; and the provision of the avoidance grooves 301 provides an avoidance space for the clamping claws on the manipulator when loading and unloading materials, which is conducive to extending the service life of the clamping claws and the fixed base 1.

[0068] Optionally, the battery cell fixing fixture further comprises a film pressing device 4 for pressing the insulating film. It should be particularly noted that a bottom support sheet is provided at the bottom of the battery cell in this embodiment, and an insulating film is provided on the bottom support sheet, and the film pressing device 4 is used to press the insulating film.

[0069] The laminating device 4 includes a support base 41 installed on the fixed base 1, a laminating assembly 42 rotatably installed on the support base 41 through a first laminating shaft 51 to press the insulating film, and a second driving assembly 43 for driving the laminating assembly 42 to rotate around the first laminating shaft 51; the laminating assembly 42 includes a laminating plate 421 rotatably installed on the first laminating shaft 51 and a laminating roller 422 rotatably installed on the laminating plate 421; the second driving assembly 43 is used to drive the laminating assembly 42 to rotate around the first laminating shaft 51 so that the laminating roller 422 presses the insulating film.

[0070] In this embodiment, the pressing principle of the film pressing device 4 is the same as the pressing principle of the pressing block 22. The film pressing assembly 42 in this embodiment can avoid the situation where the insulating film cannot be pressed. Even if the insulating film cannot be well laid on the bottom support sheet after the top cover and the insulating film are hot pressed, the film pressing roller 422 on the film pressing assembly 42 can be well pressed on the insulating film. The second driving assembly 43 includes a rotating driving device 4301, a flange 4302 fixedly connected to the rotating shaft of the rotating driving device 4301, a connecting arm 4303 rotatably connected to the flange 4302, and a sliding part 4304 rotatably connected to the connecting arm 4303, the sliding part 4304 is slidably installed on the fixed base 1, and the opposite ends of the connecting arm 4303 are respectively connected to the flange 4302 and the sliding part 4304; the sliding part 4304 is connected to the second arm 431. The rotary drive device 4301 rotates and pulls the sliding part 4304 to slide back and forth along the set direction through the connecting arm 4303, thereby changing the position of the second arm 431, so that the second arm 431 can push the film pressing plate 421 to rotate around the first film pressing shaft 51 to achieve compression or loosening of the insulating film.

[0071] Optionally, the second drive assembly 43 includes a second curved arm 431 and a second linear drive device, one end of the second curved arm 431 is rotatably connected to the end of the film pressing assembly 42 through the second film pressing shaft 52, and the other end is rotatably connected to the driving end of the second linear drive device through the third film pressing shaft 53, the first film pressing shaft 51, the second film pressing shaft 52, and the third film pressing shaft 53 are parallel to each other, and the moving path of the driving end of the second linear drive device is perpendicular to the third film pressing shaft 53. Similarly, the second linear drive device can be a cylinder, a motor screw assembly, an electric telescopic rod, a linear module, etc.

[0072] Optionally, the first driving device includes a connecting plate 232 and a driving cylinder, the driving axis of the driving cylinder is perpendicular to the third rotating shaft 13; a reset elastic member 233 is also installed between the fixed base 1 and the connecting plate 232, and when the driving cylinder stops driving, the reset elastic member 233 is reset to allow the pressing block 22 to press the battery cell. The driving cylinder is not shown in the figure. Figure 7 In the embodiment, the driving cylinder drives the connecting plate 232 to move from left to right or from right to left. Figure 7When the connecting plate 232 moves toward the center of the fixed base 1, the fixed base 21 opens to allow the battery cell to pass through. When the connecting plate 232 moves away from the center of the fixed base 1, the fixed base 21 gradually approaches and presses the battery cell on the fixed base 1.

[0073] Optionally, the battery cell fixing fixture further includes a side clamping block 6, which is fixedly connected to the adjacent connecting plate 232; when the pressing block 22 presses the battery cell, the side clamping block 6 contacts the side of the battery cell. The provision of the side clamping block 6 can press the battery cell more accurately.

[0074] Optionally, a slide rail 7 perpendicular to the third rotating shaft 13 is provided on the top surface of the fixed base 1, and the driving end of the first driving device is slidably mounted on the slide rail 7. The provision of the slide rail 7 can improve the transmission stability of the first driving device, that is, the telescopic value or displacement value of the driving end of the first driving device can be better set.

[0075] Optionally, the battery cell fixing fixture also includes a top cover positioning assembly 8 arranged on one side of the fixed base 1; the top cover positioning assembly 8 includes a support plate 81 and a positioning assembly, and the positioning assembly and the support plate 81 form a positioning station for placing the top cover; the positioning assembly includes at least two relatively arranged positioning blocks 82 and at least two relatively arranged positioning columns 83; when the battery cell is placed in the positioning station, one side of the battery cell at least contacts one positioning block 82 or at least contacts one positioning column 83. Figure 2 , Figure 4 and Figure 7 In each, two battery cell fixing jigs and a top cover positioning assembly 8 are included, and the top cover positioning assembly 8 is arranged in the middle of the two battery cell fixing jigs. In this way, the adapters of the two battery cells can be connected to the poles of the top cover at the same time, thereby improving the assembly efficiency. Optionally, the positioning block 82 and the positioning column 83 are both made of ceramic.

[0076] As described above, the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A battery cell fixing fixture, characterized in that: include: A fixed base (1) for supporting the battery cell; A pressing block (22) is rotatably mounted on one side of the top of the fixed base (1); A first driving assembly (23), comprising a first curved arm (231) and a first driving device arranged on one side of the bottom of the fixed base (1), one end of the first curved arm (231) being hinged to the pressing block (22), and the other end being hinged to a driving end of the first driving device; The first driving device drives the first curved arm (231) to move, so that the pressing block (22) rotates and presses the battery core.

2. The battery cell fixing fixture according to claim 1, characterized in that: A fixing seat (21) is arranged on the side of the fixing base (1), and the pressing block (22) is rotatably mounted on the fixing seat (21) via a first rotating shaft (11).

3. The battery cell fixing fixture according to claim 1, characterized in that: The pressing block (22) is rotatably mounted on the fixed base (1) via a first rotating shaft (11); one end of the first crank arm (231) is rotatably connected to the end of the pressing block (22) via a second rotating shaft (12); the other end is rotatably connected to the driving end of the first driving device via a third rotating shaft (13); the first rotating shaft (11), the second rotating shaft (12) and the third rotating shaft (13) are parallel to each other, and the moving direction of the driving end of the first driving device is perpendicular to the third rotating shaft.

4. The battery cell fixing fixture according to claim 3, characterized in that: The first driving device comprises a connecting plate (232) and a driving cylinder, wherein a driving shaft of the driving cylinder is perpendicular to the third rotating shaft (13); A resetting elastic member (233) is also installed between the fixed base (1) and the connecting plate (232); when the driving cylinder stops driving, the resetting elastic member (233) is reset to allow the pressing block (22) to keep pressing the battery core.

5. The battery cell fixing fixture according to claim 4, characterized in that: It also includes a side clamping block (6), wherein the side clamping block (6) is fixedly connected to the adjacent connecting plate (232); When the pressing block (22) presses the battery core, the side clamping block (6) contacts the side surface of the battery core.

6. The battery cell fixing fixture according to claim 4, characterized in that: It also includes a top cover positioning assembly (8) arranged on one side of the fixed base (1); The top cover positioning assembly (8) comprises a support plate (81) and a positioning assembly, wherein the positioning assembly and the support plate (81) form a positioning station for placing the top cover; The positioning assembly comprises at least two positioning blocks (82) arranged opposite to each other and at least two positioning posts (83) arranged opposite to each other; When the battery cell is placed in the positioning station, one side surface of the battery cell contacts at least one positioning block (82) or at least one positioning column (83).

7. The battery cell fixing fixture according to claim 3, characterized in that: The pressing block (22) is provided with a pressing portion for pressing the battery core, and the first rotating shaft (11) is located between the second rotating shaft (12) and the pressing portion.

8. The battery cell fixing fixture according to claim 1, characterized in that: At least two pressing blocks (22) are provided, and the two pressing blocks (22) are respectively provided on two opposite sides of the fixed base (1); Alternatively, a positioning vertical plate for stopping the battery core is also provided on the fixed base (1), and the positioning vertical plate and the pressing block (22) are arranged relative to each other.

9. The battery cell fixing fixture according to claim 1, characterized in that: A supporting pad (3) is provided on the fixed base (1); The opposite side edges of the support pad (3) are both provided with avoidance grooves (301) for avoiding the clamping claws.

10. The battery cell fixing fixture according to any one of claims 1 to 9, characterized in that: It also includes a film pressing device (4) for pressing the insulating film; The film pressing device (4) comprises a support seat (41) mounted on the fixed base (1), a film pressing component (42) rotatably mounted on the support seat (41) to press the insulating film, and a second driving component (43) for driving the film pressing component (42) to rotate; The film pressing assembly (42) includes a film pressing plate (421) rotatably mounted on the support seat (41) and a film pressing roller (422) rotatably mounted on the film pressing plate (421); the second driving assembly (43) is used to drive the film pressing assembly (42) to rotate relative to the support seat (41) so that the film pressing roller (422) presses the insulating film.

11. The battery cell fixing fixture according to claim 10, characterized in that: The second driving assembly (43) comprises a second curved arm (431) and a second linear driving device, one end of the second curved arm (431) is rotatably connected to the end of the film pressing assembly (42), and the other end is rotatably connected to the driving end of the second linear driving device.

Images