Winding device

Abstract

The utility model discloses a winding device and belongs to the technical field of diaphragms. The winding device comprises a rack and a winding core. The roll core comprises a barrel and a supporting body wrapping the surface of the barrel, the two ends, in the axial horizontal direction, of the barrel are connected with the rack, and the surface of the supporting body is used for winding a film material. In the direction perpendicular to the axial direction, the outer contour of the section of the supporting body is provided with a long axis and a short axis which are perpendicular to each other, the direction of the long axis is consistent with the gravity direction, and the ratio of the long axis to the short axis is larger than 1. By means of the winding device, when the membrane material is wound around the supporting body of the winding core, the stress area of the membrane material in the direction perpendicular to the gravity can be reduced, the supporting force borne by the membrane material in the direction perpendicular to the membrane face is reduced, and then the probability that the membrane material deforms due to the gravity effect is reduced.

Description

Technical Field

[0001] The present application relates to the field of diaphragm technology, and in particular to a winding device. Background Art

[0002] Lithium-ion batteries have been widely used due to their high energy density, long cycle life, light weight and small size, as well as their safety, reliability, environmental friendliness and rapid charge and discharge.

[0003] As one of the key components of lithium-ion batteries, lithium-ion battery microporous diaphragms have a direct impact on the capacity, cycle life and safety of the battery. Most lithium-ion battery diaphragm production lines use a winding device to wind up the semi-finished film material using the winding core in the winding device. In the winding device, the axial direction of the winding core is perpendicular to the direction of gravity, that is, the winding core is set horizontally.

[0004] However, currently, a cylindrical winding core is generally used for winding in a winding device. During the storage of the semi-finished film material on the cylindrical winding core, the film surface is prone to deformation. Utility Model Content

[0005] In view of the above-mentioned deficiencies, the present application provides a winding device to improve the problem in the related art that the film material wound in the winding device is prone to film surface deformation.

[0006] This application is implemented as follows:

[0007] An example of the present application provides a winding device, including a frame and a winding core; the winding core includes a cylinder and a support body wrapped around the surface of the cylinder, the two ends of the cylinder in the horizontal direction along the axial direction are connected to the frame, and the surface of the support body is used to wind the film material; in the direction perpendicular to the axial direction, the outer contour of the cross-section of the support body has a major axis and a minor axis that are perpendicular to each other, the direction of the major axis is consistent with the direction of gravity, and the ratio of the major axis to the minor axis is greater than 1.

[0008] In the above implementation process, the axial ends of the core cylinder are connected to the frame so that the axial direction of the core is perpendicular to the gravity direction, so that the film material can be wound on the core and placed horizontally, so as to facilitate storage or winding or unwinding the film material to the corresponding device. The film material wound on the surface of the core support body will be subjected to vertical downward gravity, tension along the tangent direction of the film surface, and support force along the perpendicular direction of the film surface in a state of force balance. The component of gravity along the perpendicular direction of the film surface is equal to the support force and opposite in direction. Under the condition of constant mass, the magnitude of the component of gravity along the perpendicular direction of the film surface is related to the magnitude of the angle between the gravity direction and the tangent direction of the film surface. Set the gravity to G, the component of force along the perpendicular direction of the film surface to G2, and the angle between the gravity direction and the tangent direction of the film surface to α, then G2 = Gsinα. If the angle between the gravity direction and the tangent direction of the film surface is large, the larger G2 is, in order to maintain balance, the greater the support force of the film material on the perpendicular direction of the film surface will be, which will cause the film surface to deform.

[0009] In the winding device provided in the example of the present application, in the direction perpendicular to the axial direction, the outer contour of the cross section of the support body has a long axis and a short axis that are perpendicular to each other, and the direction of the long axis is consistent with the direction of gravity. Compared with the ratio of the long axis to the short axis being less than 1, the ratio of the long axis to the short axis of the winding core provided in the present application is greater than 1, which can relatively reduce the angle α between the direction of gravity and the tangent direction of the film surface, thereby reducing the support force of the film material on the film surface in the direction perpendicular to the film surface, and reducing the probability of deformation of the film surface.

[0010] In an optional embodiment, the ratio of the major axis to the minor axis does not exceed 4.

[0011] In combination with the first aspect, in an optional implementation, the minor axis is not less than 150 mm.

[0012] In the above implementation process, the ratio of the major axis to the minor axis is greater than 1 and not more than 4, and the minor axis is not less than 150 mm, which can reduce the probability of deformation of the film surface due to gravity while improving the stability of the winding core.

[0013] In an optional embodiment, the support body is an elastic support body.

[0014] In the above implementation process, the elastic support body can release the pressure caused by changes in the membrane material such as shrinkage or expansion, and can further reduce the probability of deformation of the membrane surface.

[0015] In an optional embodiment, the outer contour of the cross section of the support body is elliptical or polygonal.

[0016] In an optional embodiment, the outer contour of the cross section of the support body is elliptical.

[0017] In the above implementation process, compared with the winding core of the prior art in which the outer contour of the cross section of the support body is circular, the winding core provided in the embodiment of the present application has an outer contour of the cross section of the support body that is elliptical, and the major axis along the gravity direction is greater than the minor axis along the horizontal direction, which can relatively reduce the angle α between the gravity direction and the tangent direction of the film surface, thereby reducing the support force of the film material on the vertical direction of the film surface and reducing the probability of deformation of the film surface. The outer contour of the cross section of the support body is elliptical and smooth, which can reduce the probability of deformation of the film material.

[0018] In combination with the first aspect, in an optional embodiment, the frame includes a support base and a bracket supported above the support base, and the bracket is connected to the end of the cylinder to support the support body away from the support base.

[0019] In the above implementation process, a bracket is arranged above the support seat, which can be used to support the cylinder, and the support body used for winding the film material is separated from the support seat to avoid the support seat from contacting the film material wound on the support body and affecting the quality of the film material.

[0020] In an optional embodiment, the bracket is a support column, and a through hole is provided inside the cylinder for being sleeved with the support column.

[0021] In the above implementation process, a through hole is provided inside the cylinder, and the through hole can be used to be sleeved with the support column to support the support body of the winding core away from the support seat.

[0022] In an optional embodiment, the cross-sectional shape of the through hole along the direction perpendicular to the axial direction is circular, elliptical, rectangular, square or diamond-shaped.

[0023] In an optional embodiment, along the axial direction of the cylinder, both ends of the cylinder extend beyond the support body.

[0024] In the above implementation process, both ends of the cylinder extend beyond the support body along the axial direction of the cylinder, which can reduce the probability that the film material wound on the support body contacts the brackets connected to the two ends of the cylinder and affects the quality of the film material. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0026] Figure 1 Schematic diagram of the force analysis of the core provided for comparison technology;

[0027] Figure 2 A schematic plan view of a winding device provided for an example of this application;

[0028] Figure 3 A cross-sectional schematic diagram of a first structure of a winding core provided in an embodiment of the present application;

[0029] Figure 4 A schematic diagram of force analysis of a first structure of a winding core provided in an embodiment of the present application;

[0030] Figure 5 A cross-sectional schematic diagram of the second structure of the winding core provided in an embodiment of the present application.

[0031] Icon: 100-cylindrical winding core; 200-membrane material; 1-winding device; 10-frame; 11-support seat; 12-bracket; 20-winding core; 21-cylinder; 211-through hole; 22-support body; 221-major axis; 222-minor axis; D1-axial direction; D2-gravity direction; D3-tangent direction of membrane surface; D4-vertical direction of membrane surface; α1-first angle; α2-second angle; G-gravity; G1-first component force; G2-second component force; F1-tension; F2-support force. DETAILED DESCRIPTION

[0032] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions.

[0034] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0035] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0036] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "long", "upper", "lower", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0037] Usually, lithium-ion battery separator production lines use winding equipment to wind up the semi-finished film materials using the winding core in the winding equipment.

[0038] like Figure 1 As shown, current winding equipment generally adopts a cylindrical winding core 100 for winding.

[0039] In the current winding equipment, the axial direction D1 of the cylindrical winding core 100 is perpendicular to the gravity direction D2, that is, the cylindrical winding core 100 is arranged horizontally.

[0040] However, the film material 200 is wound on the cylindrical winding core 100 , and during storage, the film surface of the film material 200 is easily deformed.

[0041] The applicant analyzed the reasons why the film material 200 wound on the cylindrical core 100 is prone to deformation during storage and found that the film material 200 wound on the cylindrical core 100, in a balanced state, will be subjected to a support force F2 perpendicular to the film surface. The greater the support force F2, the easier it is for the film surface to deform.

[0042] Please continue reading Figure 1 The film material 200 wound on the cylindrical winding core 100 is subjected to gravity G along the gravity direction D2, tension F1 along the film surface tangent direction D3, and support force F2 along the film surface perpendicular direction D4 in a force balanced state. There is a first angle α1 between the film surface tangent direction D3 and the gravity direction D2.

[0043] The gravity G can be decomposed into a first component force G1 along the tangent direction D3 of the membrane surface and a second component force G2 along the perpendicular direction D4 of the membrane surface. The first component force G1 is opposite to the pulling force F1 in direction and equal in magnitude; the second component force G2 is opposite to the supporting force F2 in direction and equal in magnitude to the supporting force F2.

[0044] Therefore, the larger the second component force G2 is, the larger the supporting force F2 in the direction perpendicular to the membrane surface D4 is.

[0045] The applicant believes that the probability of deformation of the membrane surface can be reduced by reducing the supporting force F2.

[0046] The applicant found that, since the magnitude of the supporting force F2 is equal to the magnitude of the second force component G2, and the second force component G2 = Gsinα1, the probability of deformation of the membrane surface can be reduced by reducing the first angle α1.

[0047] Furthermore, when the first angle α1 between the film surface tangent direction D3 and the gravity direction D2 is 90°, the support force F2 is equal to the gravity G. If the force area of ​​the film material 200 perpendicular to the gravity direction D2 is larger, the gravity G of the film material 200 is larger, the support force F2 of the film material 200 is larger, and the film material 200 is more likely to deform. Therefore, the probability of deformation of the film material 200 can be reduced by reducing the force area of ​​the film material 200 perpendicular to the gravity direction D2.

[0048] Based on this, the present application further improves the winding device 1 to improve the problem of film surface deformation to a certain extent. In order to make the purpose, technical solution and advantages of the embodiment of the present application clearer, the technical solution in the embodiment of the present application will be clearly and completely described below in conjunction with the drawings in the embodiment of the present application.

[0049] See also Figure 2 The present application example provides a winding device 1, including a frame 10 and a winding core 20.

[0050] The winding core 20 includes a cylinder 21 and a support 22 covering the surface of the cylinder 21. Both ends of the cylinder 21 in the horizontal direction of the axial direction D1 are connected to the frame 10. That is, the winding core 20 can be placed in a horizontal position through the frame 10.

[0051] It can be understood that the two ends of the cylinder 21 in the horizontal direction along the axial direction D1 are connected to the frame 10, which means that the cylinder 21 can be placed horizontally in an industrial manner, and does not mean that it is absolutely horizontal.

[0052] The surface of the support 22 is used for winding the film material 200. Figure 3 In a direction perpendicular to the axial direction D1, the outer contour of the cross section of the support body 22 has a long axis 221 and a short axis 222 that are perpendicular to each other, the direction of the long axis 221 is consistent with the gravity direction D2, and the ratio of the long axis 221 to the short axis 222 is greater than 1.

[0053] Understandably, see Figure 3 The extending direction of the major axis 221 is consistent with the gravity direction D2, and the extending direction of the minor axis 222 is consistent with the horizontal direction.

[0054] It can be understood that the ratio of the major axis 221 to the minor axis 222 is greater than 1, which means that in the cross-sectional outer contour of the support body 22 , the length of the major axis 221 along the gravity direction D2 is greater than the length of the minor axis 222 along the horizontal direction.

[0055] The present application increases the height of the winding core 20 along the gravity direction D2 and reduces the width of the winding core 20 along the horizontal direction, thereby reducing the force area and size of the film material 200 perpendicular to the gravity direction D2, and can effectively reduce the support force F2 of the film material 200 in the vertical direction D4 of the film surface, thereby reducing the probability of deformation of the film material 200.

[0056] For example, see Figure 4 The film material 200 wound on the winding core 20 is subjected to gravity G along the gravity direction D2, tension F1 along the film surface tangent direction D3, and support force F2 along the film surface perpendicular direction D4 in a force balanced state. There is a second angle α2 between the film surface tangent direction D3 and the gravity direction D2.

[0057] The gravity G can be decomposed into a first force component G1 along the tangent direction D3 of the membrane surface, and a second force component G2 along the perpendicular direction D4 of the membrane surface. The first force component G1 is opposite to the pulling force F1 in direction and equal in magnitude; the second force component G2 is opposite to the supporting force F2 in direction, and the magnitude of the supporting force F2 is equal to that of the second force component G2, and the second force component G2 = Gsinα2.

[0058] At the same height position, compared with the cylindrical winding core 100 of the comparative technology, in the winding core 20 provided by the embodiment of the present application, the second angle α2 is smaller than the first angle α1.

[0059] Therefore, compared with the cylindrical winding core 100 of the comparative technology, in the winding core 20 provided in the example of the present application, the ratio of the major axis 221 to the minor axis 222 is greater than 1, which can reduce the magnitude of the support force F2 on the membrane surface in the vertical direction D4, thereby reducing the probability of deformation of the film material 200.

[0060] The present application does not limit the specific ratio of the major axis 221 to the minor axis 222 . In some possible embodiments, the ratio of the major axis 221 to the minor axis 222 does not exceed 4.

[0061] Exemplarily, the ratio of the major axis 221 to the minor axis 222 may be in the range of one or any two of 1.01, 1.05, 1.1, 1.5, 2.0, 2.5, 3.0, 3.5 or 4.0.

[0062] Furthermore, in some possible embodiments, the size of the short axis 222 is not less than 150 mm.

[0063] Furthermore, the present application does not limit the specific shape of the cross-sectional outer contour of the support body 22 in the winding core 20. In some possible embodiments, the cross-sectional outer contour of the support body 22 may be selected from an ellipse or a polygon.

[0064] For example, please refer to Figure 3 and Figure 4 The outer contour of the cross section of the support body 22 can be elliptical.

[0065] For example, see Figure 5 The outer contour of the cross section of the support body 22 can be rectangular.

[0066] Compared with a square or other shape, the outer contour of the cross section of the support body 22 is a rectangle, and the long axis 221 along the gravity direction D2 is larger than the short axis 222 along the horizontal direction, which can relatively reduce the force area of ​​the membrane surface perpendicular to the gravity direction D2, thereby reducing the probability of deformation of the membrane material 200.

[0067] For example, under the same winding circumference, the length of the membrane surface at the horizontal side length in the square is greater than the length of the membrane surface at the horizontal side length in the rectangle. The force area of ​​the membrane material 200 wound on the support body 22 with a square cross-sectional outer contour, which is perpendicular to the gravity direction D2, is greater than the force area of ​​the membrane material 200 wound on the support body 22 with a rectangular cross-sectional outer contour, which is perpendicular to the gravity direction D2. Therefore, the supporting force F2 of the membrane material 200 wound on the support body 22 with a square cross-sectional outer contour is greater than the supporting force F2 of the membrane material 200 wound on the support body 22 with a rectangular cross-sectional outer contour, which increases the probability of deformation of the membrane material 200.

[0068] In some other possible embodiments, the outer contour of the cross section of the support body 22 may be rhombus-shaped.

[0069] Furthermore, the present application does not limit the specific material of the support body 22. In some possible embodiments, the support body 22 may be an elastic support body.

[0070] Exemplarily, the material of the elastic support body can be selected from rubber, silicone or sponge.

[0071] Furthermore, in some possible embodiments, the support body 22 may be a continuous layered structure coated on the surface of the cylinder 21 .

[0072] Alternatively, along the circumference of the cylinder 21 , the support body 22 may be provided with a plurality of strip-shaped gaps extending along the axial direction D1 .

[0073] A plurality of strip-shaped gaps extending along the axial direction D1 are provided on the support body 22 , and the strip-shaped gaps can adapt to stress changes of the film material 200 .

[0074] In some possible embodiments, the frame 10 may include a support base 11 and a bracket 12 supported above the support base 11 , wherein the bracket 12 is connected to an end of the cylinder 21 to separate the support body 22 from the support base 11 .

[0075] In some possible embodiments, the frame 10 has two support seats 11, and the two support seats 11 are spaced apart along the axial direction D1. A bracket 12 is provided on the upper side of each support seat 11 facing the other support seat 11. The bracket 12 is a support column structure, and a storage space for the winding core 20 and the film material 200 wound on the outer surface of the support body 22 is formed between the two brackets 12.

[0076] The two brackets 12 are respectively connected to the two ends of the cylinder 21 along the axial direction D1, so that the core 20 is placed horizontally, and the direction of the long axis 221 of the core 20 is consistent with the gravity direction D2, and the support body 22 and the film material 200 wound on the support body 22 can be placed between the two brackets 12 and suspended in the air, which can avoid the support seat 11 from contacting the film material 200.

[0077] The present application does not limit the specific structure of the cylinder 21. In order to facilitate the connection between the cylinder 21 and the bracket 12, in some possible embodiments, a through hole 211 extending along the axial direction D1 can be provided in the cylinder 21, that is, the cylinder 21 is a hollow tubular structure.

[0078] A support column extending a certain distance along the axial direction D1 is disposed on one side of each bracket 12 facing the other bracket 12 , and both ends of the cylinder 21 can be sleeved on the two support columns through the through holes 211 .

[0079] Furthermore, in some possible embodiments, the cross-sectional shape of the through hole 211 along the direction perpendicular to the axial direction D1 is circular, elliptical, rectangular, square or diamond-shaped.

[0080] Exemplarily, the cross-sectional shape of the through hole 211 along the direction perpendicular to the axial direction D1 is circular.

[0081] Further, in some possible embodiments, along the axial direction D1 , both ends of the cylinder 21 extend beyond the support body 22 .

[0082] Furthermore, in some possible embodiments, the cylinder 21 and the support body 22 are an integral structure.

[0083] Exemplarily, the winding core 20 may be a hollow tubular structure with an outer elliptical shape and an inner circular shape.

[0084] Exemplarily, the winding core 20 may be a hollow tubular structure with an oval outer surface and a square inner surface.

[0085] Alternatively, in some other possible embodiments, the frame 10 may include two oppositely disposed support seats 11, and the top ends of the two support seats 11 are configured to be Y-shaped openings. The two ends of the cylinder 21 can be mounted at the Y-shaped openings to support the winding core 20, and make the direction of the long axis 221 of the winding core 20 consistent with the gravity direction D2.

[0086] The above description is only the preferred embodiment of the present application and is 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 winding device, characterized in that: It comprises a frame and a winding core; the winding core comprises a cylinder and a support body wrapped on the surface of the cylinder, the two ends of the cylinder along the horizontal direction of the axial direction are connected to the frame, and the surface of the support body is used for winding the film material; in the direction perpendicular to the axial direction, the outer contour of the cross-section of the support body has a long axis and a short axis perpendicular to each other, the direction of the long axis is consistent with the direction of gravity, and the ratio of the long axis to the short axis is greater than 1.

2. The winding device according to claim 1, characterized in that: The ratio of the major axis to the minor axis does not exceed 4.

3. The winding device according to claim 2, characterized in that: The minor axis is not less than 150 mm.

4. The winding device according to claim 1, characterized in that: The support body is an elastic support body.

5. The winding device according to claim 1, characterized in that: The outer contour of the cross section of the support body is elliptical or polygonal.

6. The winding device according to claim 5, characterized in that: The outer contour of the cross section of the support body is elliptical.

7. The winding device according to claim 1, characterized in that: The frame comprises a support seat and a bracket supported above the support seat, wherein the bracket is connected to the end of the cylinder to separate the support body from the support seat.

8. The winding device according to claim 7, characterized in that: The bracket is a support column, and a through hole is provided inside the cylinder for sleeve connection with the support column.

9. The winding device according to claim 8, characterized in that: The cross-sectional shape of the through hole along the direction perpendicular to the axial direction is circular, elliptical, rectangular, square or rhombus.

10. The winding device according to claim 7, characterized in that: Along the axial direction, both ends of the cylinder exceed the support body.

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