Film stretching mechanism and film stretching and shaping device

Abstract

The utility model provides a film stretching mechanism and a film stretching and shaping device, and relates to the field of film manufacturing. The film stretching mechanism comprises two roller sets arranged at intervals along the Z axis, a gap allowing a film to pass through is formed between the two roller sets, and the Z axis is parallel to the normal direction of the film. Wherein each roller set comprises a roller or a plurality of rollers which are arranged in parallel at intervals along the X axis, each roller extends along the Y axis, each roller is configured to be capable of reciprocating along the Z axis to extrude and stretch a film, and when the two roller sets are configured to be in a stretching state, orthographic projections of the rollers of the two roller sets on the XY plane are sequentially and alternately arranged at intervals along the X axis. Through the arrangement, the two sides of the film can be evenly stressed in the stretching process, and the risk that the film is damaged in the stretching process is reduced.

Description

Technical Field

[0001] The present application relates to the field of film manufacturing, and in particular to a film stretching mechanism and a film stretching and shaping device. Background Art

[0002] Battery separator is one of the key materials for secondary batteries. For example, in lithium-ion batteries, the micropores in the battery separator can provide channels for lithium ion transmission and prevent short circuits between the positive and negative electrodes, which directly affects the battery's core performance such as energy density, safety performance, and rate performance.

[0003] During the production process of battery separators, the holes inside the battery separators are usually formed by stretching. The stretching during separator production is usually achieved by the speed difference between the stretching rollers under certain temperature conditions. This setting method has the risk of the separator being damaged during the stretching process due to uneven force on the separator. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a film stretching mechanism and a film stretching and shaping device, which can improve the risk of film, such as diaphragm, being damaged during the stretching process.

[0005] In a first aspect, an embodiment of the present application provides a film stretching mechanism, comprising: two groups of rollers arranged at intervals along the Z axis, a gap for the film to pass through is formed between the two groups of rollers, and the Z axis is parallel to the normal direction of the film; wherein each roller group comprises one roller or a plurality of rollers arranged at intervals and in parallel along the X axis, each roller extends along the Y axis, and each roller is configured to be able to move back and forth along the Z axis to squeeze and stretch the film, and when the two groups of rollers are configured to be in a stretched state, the orthographic projections of the rollers of the two groups of rollers on the XY plane are arranged alternately and at intervals along the X axis.

[0006] In the above implementation process, the two groups of rollers are respectively located on both sides of the film in the normal direction. When the two groups of rollers are configured to be in a stretched state, the orthographic projections of the rollers of the two groups of rollers on the XY plane are arranged alternately and at intervals along the X-axis, which is beneficial for the film to be stressed simultaneously and evenly on both sides during the stretching process, thereby reducing the risk of damage to the film during the stretching process.

[0007] In a possible embodiment, a heating unit for heating the roller is provided inside the roller.

[0008] In the above implementation process, the rollers are used to assist in heating both sides of the film, so that the film can be quickly heated to the required temperature, thereby improving the preparation efficiency and the stretching effect.

[0009] In one possible embodiment, the cross section of the roller is elliptical.

[0010] In the above implementation process, the surface of the roller with an elliptical cross section is smooth and has a smooth transition, thereby avoiding damage to the film during the extrusion and stretching process.

[0011] In one possible embodiment, the roller has a heated state in which the major axis of the cross section is parallel to the XY plane, and a stretched state in which the minor axis of the cross section is parallel to the XY plane.

[0012] In the above implementation process, since the cross-section of the roller is an ellipse, the film is heated by utilizing the heating state in which the long axis of the cross-section is parallel to the XY plane, which can increase the heating area and thus improve the efficiency, and the film is stretched by utilizing the stretching state in which the short axis of the cross-section is parallel to the XY plane to improve the stretching effect.

[0013] In a possible embodiment, the film stretching mechanism includes a driving mechanism, which is drivingly connected to the roller to drive the roller to switch between a heating state and a stretching state.

[0014] In the above implementation process, the driving mechanism is connected to the roller transmission to drive the roller to switch between the heating state and the stretching state, thereby realizing automatic switching between the heating state and the stretching state and reducing labor costs.

[0015] In some optional embodiments, the material of the film is a polymer film material with a high degree of orientation.

[0016] In the second aspect, an embodiment of the present application provides a film stretching and shaping device, which includes a loading area, a cold drawing area and a hot drawing area arranged in sequence; the cold drawing area is used to cold-stretch the film, and the hot drawing area is used to hot-stretch the cold-stretched film, and the cold drawing area and / or the hot drawing area are provided with the above-mentioned film stretching mechanism.

[0017] In the above implementation process, the film stretching and shaping device is set up to achieve film stretching and shaping, so that the film has a preset porosity, and is beneficial for uniform force on both sides of the film during the stretching process, thereby reducing the risk of film breakage during the stretching process.

[0018] In a possible embodiment, the film stretching and shaping device includes a stretching frame that moves back and forth in a loading area, a cold drawing area, and a hot drawing area, and the stretching frame includes: a frame body, a first fixing member, and a second fixing member, the first fixing member is arranged on the frame body and is used to fix one end of the film on the X-axis; the second fixing member is movably arranged on the frame body and is used to fix the other end of the film on the X-axis, and the second fixing member is configured to be able to approach or move away from the first fixing member along the X-axis.

[0019] In the above implementation process, the stretching frame moves back and forth between the loading area, the cold drawing area and the hot drawing area, and the tension of the film is controlled by the first fixing member and the second fixing member, so that the film can be tensioned and stretched before stretching, and then stretched to a preset elongation in the cold drawing area and then continued to be tensioned to enter the hot drawing area, and then continued to stretch, so as to realize unidirectional stretching of the film in the X-axis direction.

[0020] In a possible embodiment, the stretching frame includes a tension sensor, which is disposed on the first fixing member or the second fixing member, and is used to measure the tension of the film.

[0021] In the above implementation process, the unidirectional stretching is achieved by reciprocating motion of the roller group on both sides of the film. After stretching, the tension is measured by the tension sensor and the target stretching ratio is achieved by moving the second fixing member to the set stretching ratio position.

[0022] In a possible implementation, the first fixing member and / or the second fixing member comprises: a clamping surface in contact with the film, the clamping surface extending along the Y-axis and at least flush with the width of the film in the Y-axis.

[0023] In the above implementation process, the first fixing member and / or the second fixing member are connected to the film through the clamping surface, and the clamping surface extends along the Y-axis and is at least flush with the width of the film 130 on the Y-axis, thereby increasing the contact area between the two and making the edge of the film bear force evenly, thereby avoiding tearing of the film during the clamping process.

[0024] In a possible embodiment, each roller group includes a plurality of rollers spaced apart and arranged in parallel along the X-axis, and the cold drawing zone and the hot drawing zone are respectively provided with a detection mechanism, which is used to detect and obtain the position of the second fixing member, and the roller group is configured to move the roller located between the first fixing member and the second fixing member along the Z-axis toward the film to extrude and stretch the film.

[0025] In the above implementation process, by setting the detection mechanism, only the roller located between the first fixing member and the second fixing member can be moved along the Z axis toward the film to squeeze and stretch the film, which is beneficial to saving energy consumption and avoiding the remaining rollers squeezing and damaging the second fixing member.

[0026] In a possible implementation, the loading area includes a vacuum suction cup that can be raised and lowered in the Z-axis, and the vacuum suction cup has a bearing surface for bearing the film, and the bearing surface is provided with vacuum adsorption holes.

[0027] In the above implementation process, the setting of the vacuum suction cup can assist in making the film flat and facilitate the tensioning of the film. The lifting setting can also make the vacuum suction cup detach from the film after the film is installed and tensioned, so that the film can be subsequently stretched. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 This is a schematic diagram of the structure of a film stretching and shaping device according to an embodiment of the present application;

[0030] Figure 2 This is a schematic structural diagram of the roller group and the film in a heated state of the present application;

[0031] Figure 3 This is a schematic diagram of the structure of two groups of rollers in a stretched state in the present application.

[0032] Icons: 1000-film stretching and shaping device; 10-feeding area; 20-cold drawing area; 30-hot drawing area; 100-film stretching mechanism; 101-roller group; 102-gap; 103-roller; 105-support frame; 106-first driving mechanism; 110-stretching frame; 111-frame; 112-first fixing part; 113-second fixing part; 114-guide rail; 115-screw rod; 116-tension sensor; 120-vacuum suction cup; 130-film. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] See also Figures 1 to 3 The film stretching and shaping device 1000 includes a feeding area 10, a cold drawing area 20 and a hot drawing area 30 which are arranged in sequence. The cold drawing area 20 is used to cold-stretch the film 130, and the hot drawing area 30 is used to hot-stretch the cold-stretched film 130. The cold drawing area 20 and / or the hot drawing area 30 are provided with a film stretching mechanism 100.

[0040] The loading area 10 installs the film 130 to make the film 130 flat and taut, which is beneficial to subsequent stretching and to improve the stretching effect.

[0041] The cold-drawing zone 20 and the hot-drawing zone 30 are usually ovens with different temperatures, and the cold-drawing and hot-drawing of the film 130 are realized by different heating temperatures. The cold-drawing can form a plurality of holes inside the film 130, and then the holes in the film 130 are expanded by hot-drawing.

[0042] By setting the film stretching and shaping device 1000, the film 130 is stretched and shaped so that the film 130 has a preset porosity.

[0043] The film 130 may be selected according to actual needs. For example, the film 130 is a diaphragm.

[0044] See also Figure 2 as well as Figure 3 The film stretching mechanism 100 includes two groups of roller groups 101 arranged at intervals along the Z axis, a gap 102 is formed between the two groups of roller groups 101 for the film 130 to pass through, and the Z axis is parallel to the normal direction of the film 130; each roller group 101 includes a roller 103 or a plurality of rollers 103 arranged at intervals and in parallel along the X axis, each roller 103 extends along the Y axis, and each roller 103 is configured to be able to reciprocate along the Z axis to squeeze and stretch the film 130. When the two groups of roller groups 101 are configured to be in a stretched state, the orthographic projections of the rollers 103 of the two groups of roller groups 101 on the XY plane are arranged alternately and at intervals along the X axis.

[0045] Among them, the X-axis, Y-axis, and Z-axis are perpendicular to each other and are collectively referred to as coordinate axes, and the XY plane refers to the plane where the X-axis and the Y-axis are located.

[0046] It can be understood that the Z axis is parallel to the normal direction of the film 130, that is, when the film 130 is actually stretched, the two groups of rollers 101 are respectively located on both sides of the normal direction of the film 130. Usually, the film 130 is arranged horizontally, and the two groups of rollers 101 are located on the upper and lower sides of the film 130. The roller 103 is configured to be able to approach the film 130 along the normal direction of the film 130 to squeeze and stretch the film 130, and move to the side away from the film 130 after stretching is completed.

[0047] Each roller 103 is configured to be able to move back and forth along the Z axis to extrude and stretch the film 130, and the arrangement includes but is not limited to: the film stretching mechanism 100 includes two support frames 105 corresponding to the two groups of roller groups 101 and arranged on both sides of the film 130 in the normal direction, and each support frame 105 is provided with a first driving mechanism 106, and the first driving mechanism 106 is, for example, a cylinder or a telescopic rod. The first driving mechanism 106 is transmission-connected to the roller 103 of the corresponding roller group 101 to drive the roller 103 to move back and forth along the Z axis, thereby achieving extrusion and stretching of the film 130.

[0048] Since each roller group 101 includes one roller 103 or multiple rollers 103 spaced apart and arranged in parallel along the X-axis, each roller 103 extends along the Y-axis, and each roller 103 is configured to be able to reciprocate along the Z-axis to squeeze and stretch the film 130, that is, the film 130 is actually stretched uniaxially in the X-direction, so the above-mentioned film stretching mechanism 100 is particularly suitable for stretching highly oriented films 130.

[0049] Since the film 130 is located between the two groups of rollers 101 and before stretching, the tensioned film 130 is parallel to the XY plane. If the rollers 103 of the two groups of rollers 101 are arranged correspondingly in their projections on the XY plane, when actually stretching, the rollers 103 on both sides of the film move toward the film 130 along the Z axis at the same time so that the corresponding rollers 103 abut against each other, and it is actually impossible to simultaneously apply force to both sides of the film 130 for stretching. Therefore, in the present application, when the two groups of rollers 101 are configured to be in a stretched state, the projections of the rollers 103 of the two groups of rollers 101 on the XY plane are arranged alternately and at intervals along the X axis, so that both sides of the film 130 can be simultaneously applied force for stretching, thereby improving the uniformity of force.

[0050] That is, in the film stretching mechanism 100 provided in the present application, the two groups of roller groups 101 are respectively located on both sides of the film 130 in the normal direction. When the two groups of roller groups 101 are configured to be in a stretched state, the positive projections of the rollers 103 of the two groups of roller groups 101 on the XY plane are arranged alternately and at intervals along the X-axis, which is beneficial for both sides of the film 130 to be stressed simultaneously and evenly during the stretching process, thereby reducing the risk of damage to the film 130 during the stretching process.

[0051] The film stretching mechanism 100 may be disposed only in the cold-drawing zone 20 or only in the hot-drawing zone 30. In this embodiment, both the cold-drawing zone 20 and the hot-drawing zone 30 are provided with the film stretching mechanism 100.

[0052] Since the cold-drawing zone 20 and the hot-drawing zone 30 are ovens with different temperatures, the heating method is air heating, and the heat transfer effect is poor. In addition, some materials of the film 130, such as polypropylene film, have poor fluidity and need to be heated to a higher temperature in a shorter time. Therefore, simply relying on oven heating cannot meet the processing requirements of heating to a higher temperature in a shorter time.

[0053] Therefore, in some embodiments, a heating unit (not shown) for heating the roller 103 is disposed inside the roller 103 .

[0054] It can be understood that the roller 103 is provided with a heating unit, which means that the roller 103 is a hollow roller, and the heating unit is located inside the roller 103 . The above arrangement can not only heat the film 130 through the roller 103 , but also does not affect the surface morphology of the roller 103 .

[0055] By using the rollers 103 to auxiliary heat both sides of the film 130 , the film 130 can be quickly heated to a desired temperature, thereby improving the preparation efficiency and the stretching effect.

[0056] The heating unit may be a heating wire wound inside the roller 103 .

[0057] In order to make the temperature of the roller 103 uniform, optionally, the heating unit includes heat-conducting oil filled in the roller 103 and a heating mechanism for heat-conducting contact with the heat-conducting oil. The heating mechanism includes but is not limited to a heating wire or a heating rod.

[0058] The surface of the roller 103 is smoothly transitioned, which can avoid damaging the film 130 during the stretching process. The roller 103 can be divided into a round roller and an elliptical roller according to the different cross-sectional shapes.

[0059] In some optional embodiments, the cross-section of the roller 103 is elliptical.

[0060] The surface of the roller 103 with an elliptical cross section is smooth and has a smooth transition, thereby preventing the film 130 from being damaged during the extrusion and stretching process.

[0061] In some optional embodiments, the roller 103 has a Figure 2 The long axis of the cross section shown is parallel to the heating state of the XY plane, and Figure 3 The cross section is shown in a stretched state with the minor axis parallel to the XY plane.

[0062] Since the cross section of the roller 103 is an ellipse, the heating state in which the major axis of the cross section is parallel to the XY plane is used to heat the film 130, which can increase the heating area and thus improve the efficiency, and the stretching state in which the minor axis of the cross section is parallel to the XY plane is used to stretch the film 130 to improve the stretching effect. The second driving mechanism is connected to the roller 103 in a transmission manner to drive the roller 103 to switch between the heating state and the stretching state, thereby realizing the automatic switching between the heating state and the stretching state and reducing the labor cost.

[0063] It can be understood that when the two groups of roller groups 101 are configured to be in a stretching state, the orthographic projections of the rollers 103 of the two groups of roller groups 101 on the XY plane are arranged alternately and at intervals along the X-axis, and when the two groups of roller groups 101 are configured to be in a heating state, the orthographic projections of the rollers 103 of the two groups of roller groups 101 on the XY plane are arranged alternately and partially overlapped along the X-axis, which can effectively improve the heating efficiency without affecting the stretching effect.

[0064] In some optional embodiments, the film stretching mechanism 100 includes a second driving mechanism (not shown), which is transmission-connected to the roller 103 to drive the roller 103 to switch between a heating state and a stretching state.

[0065] The provision of the second driving mechanism is conducive to realizing the automated operation of stretching.

[0066] Among them, in order to realize the switching of the roller 103 between the heating state and the stretching state, optionally, the film stretching mechanism 100 includes a mounting frame (not shown) corresponding to the roller 103, wherein both ends of the roller 103 are rotatably mounted on the mounting frame along its axial direction, and the first driving mechanism 106 is connected to the mounting frame to drive the mounting frame to reciprocate along the Z axis, thereby synchronously driving the roller 103 to reciprocate along the Z axis, and the second driving mechanism is arranged on the mounting frame to drive the roller 103 to rotate, thereby realizing the rotation switching of the roller 103 between the heating state and the stretching state, wherein the second driving mechanism is, for example, a servo motor.

[0067] It is understandable that since stretching is required after preheating, in order to avoid the upper and lower roller groups 101 colliding with each other and squeezing and damaging the film 130 during rotation switching, when the roller 103 switches from the heating state to the stretching state, the two roller groups 101 rotate 90° in the same direction. Conversely, when the roller 103 switches from the stretching state to the heating state, the two roller groups 101 also rotate 90° in the same direction.

[0068] It should be noted that the material of the film 130 includes but is not limited to a high-orientation polymer sheet, and may also be other polymer sheets without a high orientation, and both may be stretched by the film stretching mechanism 100 described above.

[0069] In some optional embodiments, the material of the film 130 is a polymer film material with a high degree of orientation.

[0070] The film stretching mechanism 100 can be used to achieve uniaxial stretching of a polymer film 130 with a high degree of orientation and obtain a target porosity.

[0071] The polymer film material with high orientation degree includes but is not limited to polypropylene.

[0072] In some optional embodiments, Figure 1 As shown, the film stretching and shaping device 1000 includes a stretching frame 110 that moves back and forth in the loading area 10, the cold drawing area 20 and the hot drawing area 30. The stretching frame 110 includes: a frame body 111, a first fixing member 112 and a second fixing member 113. The first fixing member 112 is arranged on the frame body 111 and is used to fix one end of the film 130 on the X-axis; the second fixing member 113 is movably arranged on the frame body 111 and is used to fix the other end of the film 130 on the X-axis. The second fixing member 113 is configured to be able to approach or move away from the first fixing member 112 along the X-axis.

[0073] The stretching frame 110 moves back and forth between the loading area 10, the cold drawing area 20 and the hot drawing area 30, and controls the tension of the film 130 through the first fixing member 112 and the second fixing member 113, so that the film 130 can be tensioned and stretched before stretching, and then continue to be tensioned and enter the hot drawing area 30 after being stretched to a preset elongation in the cold drawing area 20, and then continue to stretch, so as to realize unidirectional stretching of the film 130 in the X-axis direction.

[0074] The first fixing member 112 and the second fixing member 113 are specifically, for example, clamps.

[0075] like Figure 1 As shown, the second fixing member 113 is configured to be able to approach or move away from the first fixing member 112 along the X-axis, and the setting method includes but is not limited to: the frame 111 includes two guide rails 114 arranged side by side along the Y-axis, each guide rail 114 extends along the X-axis, and the second fixing member 113 is slidably arranged on the guide rails 114 along the X-axis at both ends along the Y-axis.

[0076] Further optionally, if Figure 1 As shown, the stretching frame 110 is provided with a screw rod 115 extending along the X-axis, a screw nut (not shown) arranged on the screw rod 115, and a third driving mechanism (not shown). The screw rod 115 is axially fixed and circumferentially rotatable on the frame body 111, the second fixing member 113 is arranged on the screw nut, and the third driving mechanism is arranged on the frame body 111. The third driving mechanism is transmission-connected with the screw rod 115 to drive the screw rod 115 to reciprocate forward and reverse, thereby driving the second fixing member 113 to reciprocate along the X-axis direction. The third driving mechanism is, for example, a servo motor.

[0077] In some optional embodiments, the stretching frame 110 includes a tension sensor 116 , which is disposed on the first fixing member 112 or the second fixing member 113 , and is used to measure the tension of the film 130 .

[0078] The roller group 101 is used to reciprocate on both sides of the film 130 to achieve unidirectional stretching. After stretching, the tension is measured by the tension sensor 116 and the second fixing member 113 is moved to the set stretching ratio position to achieve the target stretching ratio.

[0079] For example, Figure 1 As shown, the tension sensor 116 is disposed on the second fixing member 113 .

[0080] In some optional embodiments, the first fixing member 112 and / or the second fixing member 113 include: a clamping surface (not shown) in contact with the film 130, the clamping surface extends along the Y-axis and is at least flush with the width of the film 130 in the Y-axis.

[0081] Through the above arrangement, the first fixing member 112 and / or the second fixing member 113 are connected to the film 130 via the clamping surface, and the clamping surface extends along the Y-axis and is at least flush with the width of the film 130 on the Y-axis, thereby increasing the contact area between the two, making the edge of the film 130 evenly stressed, and avoiding tearing of the film 130 during the clamping process.

[0082] It is understandable that, when the film 130 enters the cold drawing zone 20 and the hot drawing zone 30 for stretching, it may take multiple stretchings to reach the set stretching ratio. During the stretching process, the position of the first fixing member 112 remains unchanged, and the position of the second fixing member 113 changes with the stretching. Therefore, in some optional embodiments, such as Figure 2 As shown, each roller group 101 includes a plurality of rollers 103 spaced apart and arranged in parallel along the X-axis. The cold drawing zone 20 and the hot drawing zone 30 are respectively provided with a detection mechanism (not shown in the figure). The detection mechanism is used to detect and obtain the position of the second fixing member 113. The roller group 101 is configured to move the roller 103 located between the first fixing member 112 and the second fixing member 113 along the Z-axis toward the film 130 to extrude and stretch the film 130.

[0083] It should be noted that each roller group 101 includes a plurality of rollers 103 spaced apart and arranged in parallel along the X-axis. The plurality here refers to two, three, five, ten, etc., and those skilled in the art can make a selection according to actual needs.

[0084] It is understandable that since the position of the second fixing member 113 needs to be adjusted after stretching, the length of each roller group 101 in the X-axis direction (the length between the first roller 103 and the last roller 103 along the X-axis) is greater than the length of the film 130 in the X-axis direction before stretching.

[0085] By setting the above-mentioned detection mechanism, only the roller 103 located between the first fixing member 112 and the second fixing member 113 can be moved along the Z axis toward the film 130 to squeeze and stretch the film 130, which is beneficial to saving energy consumption and preventing the remaining rollers 103 from squeezing and damaging the second fixing member 113.

[0086] like Figure 1 As shown, in some optional embodiments, the loading area 10 includes a vacuum suction cup 120 that can be raised and lowered in the Z-axis, and the vacuum suction cup 120 has a bearing surface for bearing the film 130, and the bearing surface is provided with vacuum adsorption holes.

[0087] The arrangement of the vacuum suction cup 120 is conducive to keeping the film 130 in a flat state and being clamped and tensioned by the first fixing member 112 and the second fixing member 113. The arrangement can be raised and lowered, and the vacuum suction cup 120 can also be separated from the film 130 after the film 130 is installed and tensioned, so that the film 130 can be subsequently stretched.

[0088] Exemplarily, the vacuum suction cup 120 is located below the loading area 10 in the Z-axis direction. When adsorption is required, the vacuum suction cup 120 rises to be flush with the lower ends of the first fixing member 112 and the second fixing member 113 .

[0089] See also Figures 1 to 3 The stretching process of the film stretching and shaping device 1000 includes:

[0090] The stretching frame 110 moves to the loading area 10, the vacuum suction cup 120 is lifted up to be flush with the lower ends of the first fixing member 112 and the second fixing member 113, and the film 130 to be stretched is covered on the vacuum suction cup 120. One end of the film to be stretched in the X-axis direction is fixed by the first fixing member 112, and the film 130 to be stretched is flattened, and the other end is fixed by the second fixing member 113. The tension is set to tighten the film 130 to be stretched, and then it enters the cold drawing area 20 for stretching.

[0091] The stretching process in the cold-drawing zone 20 includes: when the stretching frame 110 enters the oven of the cold-drawing zone 20, the detection mechanism detects the position of the second fixing member 113, and under the premise of keeping the position of the second fixing member 113 unchanged, the first driving mechanism 106 moves the roller 103 located between the first fixing member 112 and the second fixing member 113 from the initial position to the film 130 along the Z axis, and the second driving mechanism puts the roller 103 in a heating state with the long axis parallel to the XY plane and sticks to the film 130 for preheating. After the preheating is completed, the first driving mechanism 106 makes the roller 103 leave the film 130, and after the second driving mechanism drives the roller 103 to rotate and switch to the stretching state, the first driving mechanism 106 drives the roller 103 to move toward the film 130 to squeeze and stretch the film 130. After the stretching is completed, the roller 103 moves away from the film 130 along the Z axis to leave the film 130 and return to the initial position, and the second fixing member 113 moves according to the set tension, and the above steps are repeated until the second fixing member 113 moves to the set stretching ratio position, that is, the current stretching step is completed.

[0092] The film 130 after cold drawing is then sent to the hot drawing zone 30 for stretching. The stretching process refers to the stretching process in the cold drawing zone 20 and is not limited here.

[0093] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A film stretching mechanism, characterized in that: It comprises two groups of rollers arranged at intervals along the Z axis, a gap is formed between the two groups of rollers for the film to pass through, and the Z axis is parallel to the normal direction of the film; Each of the roller groups includes one roller or a plurality of rollers spaced apart and arranged in parallel along the X-axis, each roller extends along the Y-axis, and each roller is configured to be able to move back and forth along the Z-axis to squeeze and stretch the film. When the two groups of roller groups are configured to be in a stretched state, the orthographic projections of the rollers of the two groups of roller groups on the XY plane are arranged alternately and spaced apart along the X-axis.

2. The film stretching mechanism according to claim 1, characterized in that: A heating unit for heating the roller is disposed inside the roller.

3. The film stretching mechanism according to claim 2, characterized in that: The cross section of the roller is elliptical.

4. The film stretching mechanism according to claim 3, characterized in that: The roller has a heated state in which the major axis of the cross section is parallel to the XY plane, and the stretched state in which the minor axis of the cross section is parallel to the XY plane.

5. The film stretching mechanism according to claim 4, characterized in that: The film stretching mechanism comprises a driving mechanism, and the driving mechanism is drivingly connected to the roller to drive the roller to switch between the heating state and the stretching state.

6. The film stretching mechanism according to any one of claims 1 to 4, characterized in that: The film is made of a polymer film material with a high degree of orientation.

7. A film stretching and shaping device, characterized in that: include: It includes a feeding area, a cold drawing area and a hot drawing area which are arranged in sequence; The cold-drawing zone is used to perform cold-drawing on the film, and the hot-drawing zone is used to perform hot-drawing on the film that has undergone the cold-drawing. The cold-drawing zone and / or the hot-drawing zone are provided with the film-drawing mechanism according to any one of claims 1 to 5.

8. The film stretching and shaping device according to claim 7, characterized in that: The film stretching and shaping device comprises a stretching frame which moves back and forth in the feeding area, the cold drawing area and the hot drawing area, and the stretching frame comprises: Frame; A first fixing member, disposed on the frame and used to fix one end of the film on the X-axis; The second fixing member is movably disposed on the frame and is used to fix the other end of the film on the X-axis. The second fixing member is configured to be able to approach or move away from the first fixing member along the X-axis.

9. The film stretching and shaping device according to claim 8, characterized in that: The stretching frame includes a tension sensor, which is arranged on the first fixing member or the second fixing member, and is used to measure the tension of the film.

10. The film stretching and shaping device according to claim 8, characterized in that: The first fixing member and / or the second fixing member comprises: a clamping surface in contact with the film, wherein the clamping surface extends along the Y-axis and is at least flush with the width of the film in the Y-axis.

11. The film stretching and shaping device according to claim 8, characterized in that: Each of the roller groups includes a plurality of rollers spaced apart and arranged in parallel along the X-axis. The cold drawing zone and the hot drawing zone are respectively provided with a detection mechanism, and the detection mechanism is used to detect and obtain the position of the second fixing member. The roller group is configured to move the roller located between the first fixing member and the second fixing member along the Z-axis toward the film to extrude and stretch the film.

12. The film stretching and shaping device according to any one of claims 7 to 11, characterized in that: The loading area includes a vacuum suction cup that can be raised and lowered in the Z axis, and the vacuum suction cup has a bearing surface for bearing the film, and the bearing surface is provided with vacuum adsorption holes.

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