A photovoltaic cell grid line printing apparatus

Abstract

The utility model discloses a photovoltaic cell grid line printing device, include: frame, screen frame, scraping device, screen frame fixedly be provided with screen, the scraping device is located screen's top, the scraping device includes support, with the rotation connection of support pivot, with the fixed connection of pivot knife rest, the knife rest is in the circumferential fixed setting of pivot and ink return knife, the utility model discloses utilize single knife rest cooperation rotation mechanism has replaced double knife rest and corresponding double lifting mechanism, has simplified the structure of grid line printing device, the utility model discloses only need to rotate knife rest pivot can change the included angle of scraper and screen simultaneously, the depth that scraper will screen press down, has provided new parameter adjustment approach for the printing process of grid line.

Description

Technical Field

[0001] This utility model relates to the field of solar cells, and specifically to a photovoltaic cell grid line printing device. Background Technology

[0002] Screen printing machines use a squeegee to force ink through the perforations of a screen onto the substrate. They are suitable for printing on materials such as paper, glass, metal, ceramics, and plastics. In the photovoltaic field, to ensure the printing quality of the grid lines (the ink is printed onto the silicon wafer surface and finally sintered to form conductive grid lines), screen printing machines are typically equipped with ink return blades.

[0003] Screen printing machines used in the photovoltaic industry typically include a squeegee and a back-inking blade fixedly connected to the same translation mechanism. Both the squeegee and the back-inking blade can move up and down independently. The working process of a screen printing machine in the photovoltaic industry includes a back-inking step and a printing step. During back-inking, the squeegee moves away from the screen, while the back-inking blade contacts the screen and gathers the ink on the screen in a first direction onto the area to be printed. During printing, the back-inking blade moves away from the screen, while the squeegee contacts the screen and moves in the opposite direction. During this movement, the squeegee squeezes the ink and forces it through the perforations of the screen to transfer it to the silicon wafer surface. However, this screen printing machine structure requires two blade holders (one squeegee holder and one back-inking blade holder) and two lifting systems, and the angle between the squeegee and the screen (also known as the printing angle) can only be achieved by using different types of squeegees.

[0004] Therefore, it is necessary to improve existing screen printing machines used in the photovoltaic field. Utility Model Content

[0005] The purpose of this invention is to provide a photovoltaic cell grid line printing device, which integrates a squeegee and a back-inking blade on a rotating blade holder, and the angle between the squeegee and the screen can be achieved by rotating the rotating blade holder.

[0006] To achieve the above technical effects, the technical solution of this utility model is as follows: a photovoltaic cell grid line printing device, including a frame, a screen frame, and an ink scraping device; the screen frame is fixedly equipped with a screen; the ink scraping device includes a support, a rotating shaft rotatably connected to the support, and a blade holder fixedly connected to the rotating shaft; the blade holder is located above the screen, and the blade holder is fixedly equipped with a scraper and an ink return blade in the circumference of the rotating shaft.

[0007] Preferably, the ink scraping device includes a pair of guide rails arranged horizontally and fixedly connected to the frame, a traveling member slidably connected to the guide rails, a bracket fixedly connected to the traveling member, a blade holder located between the two pairs of guide rails, and a rotating shaft and a rotating drive member fixedly connected.

[0008] Preferably, the traveling components are fixedly connected by a synchronizing rod, which is parallel to the rotating shaft.

[0009] Preferably, the frame and the screen frame are connected by a lifting assembly, which includes a guide and a lifting drive. The guide includes a guide rail fixedly connected to the frame and a slider slidably connected to the guide rail and fixedly connected to the screen frame.

[0010] Preferably, the frame has a top frame and a bottom frame, the guide rail is fixedly mounted on the bottom frame, and / or the lifting assembly is fixedly mounted on the top frame.

[0011] Preferably, the doctor blade and / or the ink return blade are provided with detachable blade heads.

[0012] Preferably, the doctor blade and / or the ink return blade further includes a strip-shaped elastic block with a through groove, the blade head is provided with an insertion part that engages with the through groove, and the extension direction of the through groove is parallel to the rotating shaft.

[0013] Preferably, the cross-sectional shape of the through groove is polygonal.

[0014] Preferably, it further includes a horizontal vibrating element, which is fixed and disposed at the corner of the screen.

[0015] Preferably, the blades of the doctor blade and the ink return blade are located on opposite sides of the radial direction of the rotating shaft.

[0016] The advantages and beneficial effects of this utility model are as follows: This invention utilizes a single blade holder combined with a rotating mechanism to replace a double blade holder and a corresponding double lifting mechanism, thus simplifying the structure of the grid line printing device. This invention allows for simultaneous adjustment of the angle between the squeegee and the screen, as well as the depth to which the squeegee presses down on the screen, simply by rotating the squeegee holder shaft, providing a new way to adjust parameters for the grid line printing process. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the photovoltaic cell grid line printing device in Example 1; Figure 2 yes Figure 1 Enlarged view of part A; Figure 3 This is a schematic diagram of the photovoltaic cell grid line printing device in Example 2; Figure 4 yes Figure 3 Enlarged view of part B; In the diagram: 1. Frame; 101. Top frame; 102. Base frame; 2. Screen frame; 201. Screen; 3. Support; 4. Rotating shaft; 5. Blade holder; 6. Squeegee; 601. Squeegee head; 602. Squeegee elastic block; 6021. Squeegee head through slot; 7. Ink return blade; 701. Ink return blade head; 702. Ink return blade elastic block; 7021. Ink return blade through slot; 8. Guide rail; 9. Traveling component; 10. Rotation drive component; 11. Synchronizing rod; 12. Guide rail; 13. Slider; 14. Horizontal vibration component. Detailed Implementation

[0018] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0019] Example 1

[0020] like Figure 1 and Figure 2 As shown, the photovoltaic cell grid line printing apparatus of Embodiment 1 includes a frame 1, a screen frame 2 fixedly connected to the frame 1, a screen 201 fixedly mounted on the screen frame 2, and guide rails 8 arranged in pairs in the horizontal direction and fixedly connected to the frame 1. A traveling member 9 is provided on the guide rail 8, and a bracket 3 is fixedly connected above the traveling member 9. A rotating shaft 4 is rotatably mounted between the pairs of brackets 3. The rotating shaft 4 is fixedly connected to a blade holder 5 and driven by a rotation drive member 10. The blade holder 5 is located above the screen 201. A squeegee 6 and a back-ink blade 7 are fixedly mounted on the blade holder 5 around the rotating shaft 4. A horizontal vibrating member 14 is provided at the corner of the screen 201.

[0021] Specifically, by setting supports 3 in pairs on both sides of the screen 201, the squeegee 6 and the ink return blade 7 connected to the rotating shaft 4 are more stable during operation. In the photovoltaic field, the angle between the squeegee 6 and the screen 201 is usually achieved by replacing squeegees 6 with different shapes. In this invention, the angle between the squeegee 6 or the ink return blade 7 and the screen 201 can be changed by controlling the rotation drive 10. Furthermore, with the distance between the rotating shaft 4 and the screen 201 remaining constant, rotating the rotating shaft 4 not only changes the angle between the squeegee 6 or the ink return blade 7 and the screen 201, but also changes the depth to which the squeegee 6 or the ink return blade 7 presses down on the screen 201 (this pressing depth is generally achieved in existing screen printing machines through a lifting device connected to the squeegee 6). The horizontal vibrating element 14 located at the corner of the screen 201 helps eliminate micro-air bubbles in the ink paste during vibration, improving printing quality; it also helps to make the ink paste laid on the surface of the screen 201 more even, which is beneficial for the consistency of ink paste quality printed on silicon wafers of the same batch.

[0022] The screen printing plate 201 has a stencil pattern. During screen printing, the squeegee 6 or the ink return blade 7 moves from one side of the stencil pattern to the other. Both the printing direction and the ink return direction are unidirectional and opposite. Initially, the squeegee 6 is in contact with the screen printing plate 201 and is located on one side of the stencil pattern. The battery is located below the screen printing plate 201.

[0023] The working process of the photovoltaic cell grid line printing apparatus in Example 1: First, the paste is guided to the surface of the screen 201. Then, the squeegee 6 is driven by the traveling member 9 to print along the printing direction. The paste is located in front of the printing direction of the squeegee 6. The paste is then pressed by the squeegee 6 and adhered to the silicon wafer through the hollow pattern. When the squeegee 6 moves to the other side of the screen pattern, the rotation drive 10 is controlled to make the ink return blade 7 contact the screen 201 (when the squeegee 6 rotates upward away from the screen 201, the ink return blade 7 rotates downward to contact the screen 201), and at this time the contact position between the ink return blade 7 and the screen 201 is in front of the ink in the printing direction. The traveling component 9 drives the ink return knife 7 to move horizontally along the ink return direction, so that the ink paste is spread evenly on the screen pattern again.

[0024] In the above workflow, activating the horizontal vibration element 14 before printing helps the ink spread more quickly and evenly on the surface of the screen 201. When the blades of the doctor blade 6 and the back-ink blade 7 are located on opposite sides of the radial direction of the rotating shaft 4, the rotating shaft 4 is more stable during rotation, which helps improve printing stability.

[0025] Example 2

[0026] like Figure 3 and Figure 4 As shown, the photovoltaic cell grid line printing apparatus of Embodiment 2 is based on Embodiment 1, except that it also includes a synchronizing rod 11 that is parallel to the rotating shaft 4 and fixedly connected to the group of traveling members 9. After setting the synchronizing rod 11, even if the traveling member 9 on one side runs at a slightly slower speed, the rotating shaft 4 is still perpendicular to the printing direction, which is beneficial to improving the printing quality (when it is not perpendicular, the paste will slowly converge to the side where the squeegee 6 lags behind, resulting in uneven grid line height on the same silicon wafer).

[0027] In the photovoltaic cell grid line printing apparatus of Example 2, the frame 1 has a top frame 101 and a bottom frame 102, and the guide rail 8 is fixed on the bottom frame 102.

[0028] The top frame 101 is connected to the screen frame 2 via a lifting assembly. The lifting assembly includes a guide and a lifting drive. The guide includes a guide rail 12 fixedly connected to the top frame 101 and a slider 13 slidably connected to the guide rail 12 and fixedly connected to the screen frame 2. This structural design improves space utilization. The guide rail 12 is fixed to the top frame 101 (the drive mechanism of the slider 13 is located above the screen 201), thus not obstructing the transport of silicon wafers.

[0029] In the photovoltaic cell grid line printing apparatus of Example 2, for ease of machine maintenance, the squeegee 6 and the ink return blade 7 are equipped with detachable blade heads. More specifically, the squeegee 6 consists of a squeegee elastic block 602 and a squeegee head 601, with the squeegee elastic block 602 fixedly connected to the blade holder 5. A squeegee head through groove 6021 is provided on the side of the squeegee elastic block 602 opposite to the blade holder 5, and the squeegee head 601 has an insertion part that engages with this through groove. The extension direction of the through groove is parallel to the rotating shaft 4. The squeegee head 601 is fixed to the squeegee elastic block 602 through the insertion engagement, facilitating disassembly. The squeegee elastic block 602 provides a buffer for the contact between the squeegee 6 and the screen 201, extending the service life of the screen 201. To ensure a tighter connection between the squeegee head through groove 6021 and the squeegee head 601 and reduce relative displacement between them, the cross-sectional shape of the squeegee head through groove 6021 is polygonal.

[0030] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A photovoltaic cell grid line printing device, characterized in that... ,include: frame; A screen frame, in which the screen is fixedly mounted; A doctor blade device includes a bracket, a rotating shaft rotatably connected to the bracket, and a blade holder fixedly connected to the rotating shaft; The blade holder is located above the screen, and a scraper and a back-inking blade are fixedly arranged on the blade holder around the rotating shaft.

2. The photovoltaic cell grid line printing apparatus according to claim 1, characterized in that, The ink scraping device includes a pair of guide rails arranged horizontally and fixedly connected to the frame, and a traveling component slidably connected to the guide rails. The bracket is fixedly connected to the walking component; The tool holder is located between two pairs of guide rails; The rotating shaft and the rotation drive are fixedly connected.

3. The photovoltaic cell grid line printing apparatus according to claim 2, characterized in that, The traveling components are fixedly connected by a synchronizing rod, which is parallel to the rotating shaft.

4. The photovoltaic cell grid line printing apparatus according to claim 2, characterized in that, The frame and the screen frame are connected by a lifting assembly; The lifting assembly includes a guide and a lifting drive component; The guide includes a guide rail fixedly connected to the frame and a slider slidably connected to the guide rail and fixedly connected to the screen frame.

5. The photovoltaic cell grid line printing apparatus according to claim 4, characterized in that, The frame has a top frame and a bottom frame, and the guide rail is fixedly mounted on the bottom frame; And / or the lifting assembly is fixedly mounted on the top frame.

6. The photovoltaic cell grid line printing apparatus according to claim 1, characterized in that, The doctor blade and / or the ink return blade are provided with detachable blade heads.

7. The photovoltaic cell grid line printing apparatus according to claim 6, characterized in that, The doctor blade and / or the ink return blade also include a strip-shaped elastic block with a through groove; The cutting head is provided with a plug-in portion that engages with the through groove; The extension direction of the through groove is parallel to the rotating shaft.

8. The photovoltaic cell grid line printing apparatus according to claim 7, characterized in that, The cross-sectional shape of the through groove is polygonal.

9. The photovoltaic cell grid line printing apparatus according to claim 1, characterized in that, It also includes a horizontal vibrating element, which is fixed and disposed at the corner of the screen.

10. The photovoltaic cell grid line printing apparatus according to claim 1, characterized in that, The blades of the doctor blade and the ink return blade are located on both sides of the radial direction of the rotating shaft.

Images