Screen printing plate structure

Abstract

The utility model relates to the technical field of solar cell production equipment, and discloses a screen printing plate structure which comprises a screen printing plate body, the screen printing plate body comprises a first surface close to a solar cell and a second surface away from the solar cell, and the screen printing plate body comprises screen cloth. The screen cloth comprises a plurality of mutually parallel screen cloth strips, the plurality of screen cloth strips are arranged at intervals along a first direction, a trunking is formed between the adjacent screen cloth strips, the trunking is used for allowing slurry to penetrate, so that the slurry forms an auxiliary grid on the solar cell, and the first direction is a direction perpendicular to the auxiliary grid; the reinforcing structure is arranged on the second surface, the reinforcing structure comprises a plurality of first reinforcing ribs, and any first reinforcing rib is connected with the multiple mesh cloth strips. According to the screen structure, the mechanical property of the screen structure can be improved, so that the service life of the screen structure is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cell production equipment, in particular to a screen plate structure. Background Art

[0002] In the process of preparing the electrodes of a solar cell, it is necessary to print the paste onto the solar cell by means of a screen plate structure. To further reduce the use cost of the paste, it is necessary to reduce the width of the wire diameter of the screen plate structure and control the transmittance of the paste. However, due to the narrow wire diameter, the mechanical properties of the screen plate structure will be reduced to a certain extent, affecting the service life of the screen plate structure, which undoubtedly increases the cost of replacing and repairing the screen plate structure. Summary of the Utility Model

[0003] An embodiment of the utility model discloses a screen plate structure, which has good tensile strength and can effectively improve the service life of the screen plate structure.

[0004] An embodiment of the present application provides a screen plate structure, which includes:

[0005] A screen plate body, the screen plate body includes a first surface close to the solar cell and a second surface facing away from the solar cell. The screen plate body includes a screen cloth, and the screen cloth includes a plurality of screen cloth strips arranged in parallel with each other. The plurality of screen cloth strips are arranged at intervals in a first direction, and a wire groove is formed between adjacent screen cloth strips. The wire groove is used for passing through the paste so that the paste forms a sub-grid on the solar cell. The first direction is perpendicular to the direction of the sub-grid;

[0006] A strengthening structure, the strengthening structure is arranged on the second surface, and the strengthening structure includes a plurality of first reinforcing ribs. Any one of the first reinforcing ribs is respectively connected to a plurality of screen cloth strips.

[0007] Further, the plurality of first reinforcing ribs all extend along the first direction, and the plurality of first reinforcing ribs are arranged at intervals perpendicular to the first direction.

[0008] Further, the distance between adjacent first reinforcing ribs is the same.

[0009] Further, the diameter of the first reinforcing rib is 4μm to 20μm; and / or,

[0010] The material of the first reinforcing rib includes one of stainless steel and nickel-based alloy; and / or,

[0011] The material of the screen cloth includes one of stainless steel and nickel-based alloy.

[0012] Furthermore, the strengthening structure further includes a plurality of second reinforcing ribs arranged at intervals along the first direction. Any one of the second reinforcing ribs is respectively connected to a plurality of the first reinforcing ribs. The plurality of first reinforcing ribs all extend perpendicular to the first direction. The second reinforcing ribs are disposed on the second surface of the mesh fabric.

[0013] Furthermore, the number of the first reinforcing ribs is more than the number of the second reinforcing ribs.

[0014] Furthermore, the ratio of the number of the first reinforcing ribs to the number of the second reinforcing ribs is 2:1 to 3:1.

[0015] Furthermore, the mesh number of the strengthening structure is 100 mesh to 400 mesh; and / or,

[0016] the diameter of the second reinforcing rib is 4 μm to 20 μm; and / or,

[0017] the material of the second reinforcing rib includes one of stainless steel and nickel-based alloy.

[0018] Furthermore, any one of the wire grooves penetrates the mesh fabric perpendicular to the first direction.

[0019] Furthermore, the screen printing plate structure further includes a screen frame. The screen printing plate body is disposed within the screen frame. Both ends of the strengthening structure are connected to the screen frame, and both ends of the mesh fabric are connected to the screen frame.

[0020] Furthermore, the screen printing plate structure further includes a polyester mesh. The polyester mesh is connected to the screen frame. The screen printing plate body is disposed in the middle area of the polyester mesh. The first surface of the screen printing plate body is connected to the polyester mesh, and the area of the screen printing plate body is smaller than the area of the polyester mesh.

[0021] Compared with the prior art, the present application has at least the following beneficial effects:

[0022] The present application provides a stencil structure, which includes a stencil body and a strengthening structure. The stencil body includes a first surface close to the solar cell and a second surface facing away from the solar cell. The stencil body further includes a screen cloth, which includes a plurality of screen cloth strips parallel to each other. The plurality of screen cloth strips are arranged at intervals in a first direction, and a wire groove is formed between adjacent screen cloth strips. The wire groove is a permeation area for the paste. Therefore, when the paste permeates through the wire groove to the surface of the solar cell, a sub-grid will be formed on the surface of the solar cell. Among them, the first direction is perpendicular to the sub-grid. Moreover, the present application further provides a strengthening structure on the second surface of the stencil structure. The strengthening structure includes a plurality of first reinforcing ribs, and any one of the reinforcing ribs is respectively connected to a plurality of screen cloth strips. Since the first reinforcing ribs connect the plurality of screen cloth strips, it enables the screen cloth strips to have tensile force in the first direction, which is beneficial to improving the Kang Le strength of the stencil structure in the first direction, avoiding the phenomenon of plate explosion during the printing process, increasing the service life of the stencil structure, and reducing the maintenance and replacement costs. In addition, since the first reinforcing ribs are arranged on the second surface and do not affect the penetration of the paste, the flatness of the sub-grid printed by using this stencil structure is high, and the uniformity of the sub-grid wire diameter is good, thus effectively reducing the resistance of the grid lines of the solar cell and improving the photoelectric conversion efficiency of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 is a schematic structural diagram of the stencil version structure provided by the embodiment of the present application;

[0025] Figure 2 is a schematic structural diagram of the screen cloth provided by the embodiment of the present application;

[0026] Figure 3 is a schematic structural diagram of the strengthening structure provided by the embodiment of the present application;

[0027] Figure 4 is a schematic structural diagram of the stencil structure of the prior art provided by the embodiment of the present application;

[0028] Figure 5 is a schematic structural diagram of the stencil frame provided by the embodiment of the present application;

[0029] Figure 6 is a schematic structural diagram of the polyester screen provided by the embodiment of the present application.

[0030] Icon: 1. Mesh version body; 11. Mesh cloth; 111. Mesh cloth strip; 112. Mesh cloth block; 12. Wire groove; 2. Reinforcement structure; 21. First reinforcing rib; 22. Second reinforcing rib; 3. Mesh frame; 4. Polyester mesh; Y. First direction. Detailed implementation mode

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

[0032] In the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation.

[0033] Moreover, in addition to being able to represent the orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, the meaning of "a plurality" is two or more.

[0035] Next, the technical solutions provided by the present invention will be further described in conjunction with the embodiments and the accompanying drawings.

[0036] The manufacturing cost of solar cells includes silicon wafer cost, paste cost, power cost, labor cost, and depreciation cost. Among them, the paste cost accounts for about 8% of the manufacturing cost of solar cells and about 33% of the total non-silicon cost. Therefore, it is particularly urgent to reduce paste loss in the entire cell production process.

[0037] Currently, the paste content is reduced by decreasing the wire diameter of the stencil structure. However, for the commonly used stencil structure of the wire mesh type, if the wire diameter of the secondary grid prepared therefrom is small, during the printing process, a part of the paste will be brought back after the wire mesh rebounds, resulting in a significant reduction in the flatness of the surface of the secondary grid after printing. Furthermore, the stability of current transmission is reduced, the short-circuit current decreases, and further the battery conversion efficiency decreases. For the stencil structure prepared by the nanoimprinting technology, there is no obstruction of the wire in the grid line area, and the flatness of the grid line after printing is high. Moreover, the wire diameter of the grid line can be further reduced, effectively reducing the consumption of the paste. However, the stencil structure prepared by the nanoimprinting technology has poor tensile strength in the direction perpendicular to the secondary grid. During the printing process, when the squeegee is pressed down and the stencil structure deforms in this direction, the stencil structure is difficult to withstand the pressure applied by the squeegee, making it extremely easy to have the phenomenon of plate explosion during the printing process, reducing the service life of the stencil structure.

[0038] Based on the above problems, the present application provides a stencil structure, which can improve the mechanical properties of the stencil structure, thereby improving the service life of the stencil structure.

[0039] An embodiment of the present application discloses a stencil structure, as Figures 1 to 6 shown. This stencil structure is used for printing the electrodes of a solar cell, and the stencil structure includes:

[0040] A stencil body 1, the stencil body 1 includes a first surface close to the solar cell and a second surface facing away from the solar cell. The stencil body 1 includes a mesh cloth 11, the mesh cloth 11 includes a plurality of mesh cloth strips 111 arranged in parallel with each other, the plurality of mesh cloth strips 111 are arranged at intervals along a first direction Y, and a wire groove 12 is formed between adjacent mesh cloth strips 111. The wire groove 12 is used to penetrate the paste, so that the paste forms a secondary grid on the solar cell. The first direction Y is the direction perpendicular to the secondary grid;

[0041] A strengthening structure 2, the strengthening structure 2 is arranged on the second surface, and the strengthening structure 2 includes a plurality of first reinforcing ribs 21, and any one of the first reinforcing ribs 21 is respectively connected to the plurality of mesh cloth strips 111.

[0042] The stencil structure provided by this application includes a stencil body 1 and a strengthening structure 2. The stencil body 1 includes a screen cloth 11, and the screen cloth 11 includes a plurality of screen cloth strips 111 that are parallel to each other. The plurality of screen cloth strips 111 are arranged at intervals in the first direction Y. A wire groove 12 is formed between adjacent screen cloth strips 11. Therefore, when a squeegee acts on the slurry, the slurry will pass through the wire groove 12, thereby forming a sub-grid on the solar cell. Among them, the first direction Y is perpendicular to the sub-grid. In addition, since the strengthening structure 2 is provided on the second surface of the stencil body 1 and the strengthening structure 2 includes a plurality of first reinforcing ribs 21, and any one of the first reinforcing ribs 21 is respectively connected to the plurality of screen cloth strips 111, under the connection of the first reinforcing ribs 21, the screen cloth strips 111 have a certain tensile force in the first direction Y, which helps to improve the tensile resistance of the stencil structure in the first direction Y, can effectively improve the service life of the stencil structure, and reduce the maintenance and replacement costs of the stencil structure. And, since the first reinforcing ribs 21 are provided on the second surface, during the printing process, it will not affect the penetration of the slurry, so that the flatness of the printed sub-grid is relatively high, and the uniformity of the wire diameter of the sub-grid is high, which can effectively reduce the resistance of the grid lines of the solar cell and improve the photoelectric conversion efficiency of the solar cell.

[0043] In addition, by using the stencil structure of this application, the width of the prepared sub-grid is 4μm to 11μm, thereby effectively reducing the consumption of the slurry, reducing the use cost of the slurry, and improving the production efficiency.

[0044] Furthermore, as Figure 3 shown, the plurality of first reinforcing ribs 21 all extend along the first direction Y, and the plurality of first reinforcing ribs 21 are arranged at intervals perpendicular to the first direction Y. By adopting the above setting method, when the squeegee is located in a certain area of the stencil, the force uniformity of the stencil structure in this area is high, which is beneficial to improving the service life of the stencil structure.

[0045] In addition, in order to ensure the force uniformity of each area of the stencil structure and avoid the phenomenon of local bursting due to poor force uniformity, the distance between adjacent first reinforcing ribs 21 is set to be the same, which helps to improve the service life of the stencil structure.

[0046] Furthermore, the diameter of the first reinforcing rib 21 is 4μm to 20μm. When the diameter of the first reinforcing rib 21 is within the above range, it can not only ensure good tensile strength of the stencil structure, but also ensure the performance of the printed sub-grid structure. When the diameter of the first reinforcing rib 21 is too thin, the strength of the manufactured stencil structure is too low to effectively ensure the mechanical effect of the stencil structure and affect its service life; when the diameter of the first reinforcing rib 21 is too thick, the thickness of the stencil structure increases, the weight increases, which is not conducive to operation, and being too thick will also affect the penetration of the slurry, making it difficult to ensure the integrity and high uniformity of the prepared sub-grid structure.

[0047] In addition, the material of the first reinforcing rib 21 includes one of stainless steel and nickel-based alloy; the material of the mesh cloth 11 includes one of stainless steel and nickel-based alloy.

[0048] Furthermore, as Figure 3 shown, the reinforcing structure 2 further includes a plurality of second reinforcing ribs 22 arranged at intervals along the first direction Y. Any one of the second reinforcing ribs 22 is respectively connected to a plurality of first reinforcing ribs 21. The plurality of first reinforcing ribs 21 all extend perpendicular to the first direction Y. The second reinforcing ribs 22 are arranged on the second surface of the mesh cloth 11.

[0049] The arrangement of the second reinforcing ribs 22 of the screen plate structure of the present application, on the one hand, the second reinforcing ribs 22 are respectively connected to a plurality of first reinforcing ribs 21, so it plays a role in fixing the first reinforcing ribs 21, thereby preventing the first reinforcing ribs 21 from shifting when stressed, ensuring that the first reinforcing ribs 21 can fully play their role, and thus ensuring that the screen plate structure has a high tensile strength; on the other hand, the second reinforcing ribs 22 can also enhance the tensile force of the mesh cloth 11 in the direction perpendicular to the first direction Y, further reducing the deformation, improving the service life of the screen plate structure, and reducing the maintenance and replacement costs of the screen plate structure.

[0050] In addition, since the mesh cloth strips 111 of the present application have a tensile effect in the direction perpendicular to the first direction Y, the number of the first reinforcing ribs 21 is set to be more than the number of the second reinforcing ribs 22. Such an arrangement not only effectively ensures the mechanical effect of the screen plate structure, but also reduces the number of the second reinforcing ribs 22 used, thereby reducing the production and processing costs. And it can also reduce the weight of the screen plate structure, thereby improving the operation convenience and production efficiency.

[0051] Furthermore, the ratio of the number of the first reinforcing ribs 21 to the number of the second reinforcing ribs 22 is 2:1 to 3:1. When the number of the first reinforcing ribs 21 and the number of the second reinforcing ribs 22 satisfy the above relationship, it can not only ensure the mechanical effect of the screen plate structure, but also reduce the production costs of the first reinforcing ribs and the second reinforcing ribs.

[0052] Furthermore, the mesh number of the reinforcing structure 2 is 100 mesh to 400 mesh. Among them, the mesh number refers to the number of holes per unit length. The mesh number is related to the number of the first reinforcing ribs 21 and the second reinforcing ribs 22. The higher the mesh number, the more the number of the first reinforcing ribs and the second reinforcing ribs, which is more conducive to improving the mechanical effect of the screen plate structure and the service life of the screen plate structure.

[0053] Moreover, the diameter of the second reinforcing rib 22 is 4 μm to 20 μm. When the diameter of the second reinforcing rib 22 is within the above range, not only can the fixing effect of the second reinforcing rib 22 on the first reinforcing rib 21 be ensured to be good, thus avoiding the offset of the first reinforcing rib 21 when stressed, effectively enhancing the tensile strength of the screen plate structure in the first direction Y, but also it can cooperate with the screen cloth strip 11 to enhance the tensile strength of the screen plate structure perpendicular to the first direction Y, and improving the service life of the screen plate structure. When the diameter of the second reinforcing rib 22 is too thin, the fixing effect on the first reinforcing rib 21 is poor, it is difficult to ensure the mechanical effect of the screen plate structure, and the service life is affected; when the diameter of the second reinforcing rib 22 is too thick, the thickness of the screen plate structure increases, the weight increases, which is not conducive to operation and reduces the production efficiency.

[0054] In addition, the material of the second reinforcing rib 22 includes one of stainless steel and nickel-based alloy.

[0055] Furthermore, any one of the wire grooves 12 penetrates through the screen cloth 11 perpendicular to the first direction Y. Therefore, the flatness of the sub-grid structure obtained by printing the solar cell is good. Especially for the intersection area of the main grid and the sub-grid, the height of the paste in this area after printing is relatively high, which is conducive to the subsequent welding of the photovoltaic module, reducing the phenomenon of broken grid in welding, ensuring the stability of welding, and thus contributing to improving the photoelectric conversion efficiency of the solar cell.

[0056] In order to improve the tensile force of the screen plate structure, a plurality of screen cloth blocks 112 are also provided in the area of the wire groove 12. As Figure 4 shown, any one of the screen cloth blocks 112 connects the adjacent screen cloth strips 111. The position of any one of the screen cloth blocks 11 corresponds to the intersection area of the main grid and the sub-grid. The setting of the screen cloth blocks 112 helps to improve the tensile strength of the screen plate structure in the first direction Y. However, for this setting method, the height of the paste in the intersection area of the main grid and the sub-grid is relatively low, which is not conducive to the subsequent welding of the photovoltaic module and is prone to the phenomenon of broken welding, thus affecting the photoelectric conversion efficiency of the solar cell; while the present application adopts the setting method of the reinforcing structure 2, which can not only effectively increase the tensile force of the screen plate structure, but also set the wire groove 12 to penetrate perpendicular to the first direction Y, thus ensuring the stability of the welding of the photovoltaic module. That is to say, the design method of the screen plate structure of the present application not only improves the service life of the screen plate structure, but also the performance of the grid lines printed with this screen plate structure is good, which is conducive to improving the photoelectric conversion efficiency of the solar cell.

[0057] Furthermore, as Figure 5 shown, the screen plate structure further includes a screen frame 3. The screen plate body 1 is arranged inside the screen frame 3. Both ends of the reinforcing structure 2 are connected to the screen frame 3, and both ends of the screen cloth 11 are connected to the screen frame 3. Among them, the screen frame 3 is used to fix the reinforcing structure 2 and the screen plate body, so that it can withstand the force of the screen breaking and ensure the stability during printing.

[0058] Further, as Figure 6 shown, the screen plate structure further includes a polyester mesh 4. The polyester mesh 4 is connected to the screen frame 3. The screen plate body 1 is disposed in the middle area of the polyester mesh 4. The first surface of the screen plate body 1 is connected to the polyester mesh 4, and the area of the screen plate body 1 is smaller than the area of the polyester mesh 4.

[0059] Among them, the polyester mesh 4 has a good supporting effect on the screen plate body 1, which helps to improve the service life of the screen plate structure, reduce the costs of maintenance and replacement, and the area of the screen plate body 1 can be set to adapt to the size of the solar cell, reduce the area of the screen plate body 1, and reduce the production cost.

[0060] The above has introduced in detail a screen plate structure disclosed in an embodiment of the present application. Specific examples are used herein to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand a screen plate structure. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A screen structure for printing electrodes of solar cells, characterized in that: The screen structure comprises: A mesh body, the mesh body comprising a first surface close to the solar cell and a second surface away from the solar cell, the mesh body comprising a mesh, the mesh comprising a plurality of mesh strips parallel to each other, the plurality of mesh strips being arranged at intervals along a first direction, wire grooves being formed between adjacent mesh strips, the wire grooves being used to penetrate slurry so that the slurry forms a secondary grid on the solar cell, the first direction being a direction perpendicular to the secondary grid; A reinforcing structure is arranged on the second surface, and the reinforcing structure includes a plurality of first reinforcing ribs, and any of the first reinforcing ribs is respectively connected to the plurality of mesh strips.

2. The screen structure according to claim 1, characterized in that: The plurality of first reinforcing ribs all extend along the first direction, and the plurality of first reinforcing ribs are arranged at intervals in a direction perpendicular to the first direction.

3. The screen structure according to claim 2, characterized in that: The spacings between adjacent first reinforcing ribs are the same.

4. The screen structure according to claim 1, characterized in that: The diameter of the first reinforcing rib is 4 μm to 20 μm; and / or, The material of the first reinforcing rib includes one of stainless steel and nickel-based alloy; and / or, The material of the mesh cloth includes one of stainless steel and nickel-based alloy.

5. The screen structure according to claim 1, characterized in that: The reinforcement structure also includes a plurality of second reinforcement ribs arranged at intervals along the first direction, any of the second reinforcement ribs is respectively connected to a plurality of the first reinforcement ribs, the plurality of the first reinforcement ribs all extend perpendicular to the first direction, and the second reinforcement ribs are arranged on the second surface of the mesh.

6. The screen structure according to claim 5, characterized in that: The number of the first reinforcing ribs is greater than the number of the second reinforcing ribs.

7. The screen structure according to claim 6, characterized in that: The ratio of the number of the first reinforcing ribs to the number of the second reinforcing ribs is 2:1 to 3:

1.

8. The screen structure according to claim 5, characterized in that: The mesh number of the reinforcement structure is 100 to 400 meshes; and / or, The diameter of the second reinforcing rib is 4 μm to 20 μm; and / or, The material of the second reinforcing rib includes one of stainless steel and nickel-based alloy.

9. The screen structure according to claim 1, characterized in that: Any of the wire grooves passes through the mesh in a direction perpendicular to the first direction.

10. The screen structure according to claim 1, characterized in that: The screen structure also includes a screen frame, the screen body is arranged in the screen frame, two ends of the reinforcement structure are connected to the screen frame, and two ends of the mesh cloth are connected to the screen frame.

11. The screen structure according to claim 10, characterized in that: The screen structure also includes a polyester screen, which is connected to the screen frame. The screen body is arranged in the middle area of ​​the polyester screen, the first surface of the screen body is connected to the polyester screen, and the area of ​​the screen body is smaller than that of the polyester screen.

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