A special-shaped PCB printing machine and a printing method

Abstract

This invention relates to the field of circuit board printing technology, specifically disclosing a shaped PCB printing machine and printing method, suitable for printing on shaped circuit boards with raised structures on the top surface. The shaped PCB printing machine includes: a printing platform; a screen printing stencil with raised bulges; a vision recognition mechanism; and a squeegee module capable of rotating around the raised bulge, having at least a translational degree of freedom in the horizontal direction and a rotational degree of freedom about a vertical axis. Guided by the vision recognition mechanism, the squeegee module performs a rotational printing operation along the periphery of the raised bulge in the planar region of the top surface of the screen printing stencil near the raised bulge; and performs a linear translational printing operation in the planar region of the top surface of the screen printing stencil away from the raised bulge. The shaped PCB printing machine and printing method provided by this invention solve the problem that existing printing equipment cannot print on shaped circuit boards with raised structures.

Description

Technical Field

[0001] This invention relates to the field of circuit board printing technology, and in particular to a shaped PCB printing machine and printing method. Background Technology

[0002] In PCB printing, solder paste printing equipment is the core component for achieving high-precision coating. Typically, the equipment includes a printing platform to support the circuit board, a silkscreen stencil covering the board, a squeegee assembly above the stencil, and a drive unit that drives the squeegee assembly to reciprocate linearly along the stencil surface. Most mainstream drive solutions employ three-way or two-way direct-drive modules, controlling the squeegee's translation in the X, Y, and Z directions to scrape and fill the solder paste, thus forming a precise solder paste pattern in designated areas of the circuit board.

[0003] However, as electronic products evolve towards miniaturization, high integration, and irregular shapes, the surface of some specially designed printed circuit boards is not entirely flat, but rather has a three-dimensional structure with localized upward bulges. To match these board types, the screen printing stencil also needs to be made into a corresponding non-planar shape with localized arches.

[0004] In this context, the design limitations of traditional squeegee drive units, which only possess translational freedom, become increasingly apparent. When the squeegee assembly moves across the stencil surface, it is highly susceptible to interference with the stencil's raised areas. Because existing drive mechanisms lack the freedom to rotate the squeegee assembly around its axis, it cannot adaptively adjust its posture during travel, making it difficult to properly scrape along the circumferential contour of the stencil raised areas. This results in uneven and incomplete solder paste coating around the raised areas, severely impacting printing quality and product reliability.

[0005] Therefore, the motion mechanism of existing printing equipment is no longer able to meet the process requirements when faced with irregularly shaped PCBs with raised structures on the surface. It is urgent to innovate and improve the equipment to enhance its ability to adapt to complex board shapes.

[0006] The information disclosed in this background section is included only to enhance the understanding of the context of this disclosure, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] One objective of this invention is to provide an irregular PCB printing machine and printing method that can solve the problem that existing printing equipment cannot perform printing operations on irregularly shaped circuit boards with raised structures.

[0008] To achieve the above objectives, in one aspect, the present invention provides an irregularly shaped PCB printing machine, suitable for printing irregularly shaped circuit boards with a raised structure on the top surface, comprising:

[0009] A printing platform for receiving the irregularly shaped circuit board;

[0010] A screen printing stencil is located above the printing platform, and a stencil protrusion is provided at the position corresponding to the protruding structure of the irregularly shaped circuit board;

[0011] A visual recognition mechanism is used for visual positioning of the steel mesh protrusions;

[0012] The rotatable scraper module is located above the screen printing steel mesh and has at least a translational degree of freedom to move horizontally and a rotational degree of freedom to rotate about a vertical axis.

[0013] The retractable scraper module is configured as follows:

[0014] Guided by the visual recognition mechanism, a rotating printing operation is performed along the periphery of the convex bulge in the planar area of ​​the top surface of the screen-printed stencil near the convex bulge; and a linear translation printing operation is performed in the planar area of ​​the top surface of the screen-printed stencil away from the convex bulge.

[0015] Optionally, the retractable scraper module includes:

[0016] Rotating platform;

[0017] The platform rotary drive mechanism has its drive end connected to the rotary platform and is used to drive the rotary platform to rotate around the vertical axis.

[0018] The scraper assembly is mounted on the rotating platform and rotates with the rotating platform around the vertical axis;

[0019] The translation drive module has its drive end connected to the rotating platform and is used to drive the rotating platform to perform translational reciprocating motion.

[0020] Optionally, the rotating platform includes an upper platform rotating plate connected to the drive end of the platform rotation drive mechanism, a lower platform rotating plate spaced apart from or even below the upper platform rotating plate, and a platform connecting column connecting the upper platform rotating plate and the lower platform rotating plate.

[0021] Optionally, the scraper assembly includes:

[0022] The scraper direct drive mechanism is installed on the side of the lower platform turntable close to the upper platform turntable, and the drive end protrudes to the bottom of the lower platform turntable;

[0023] The self-leveling blade holder is located below the lower platform rotating plate and is connected to the drive end of the scraper direct drive mechanism;

[0024] The scraper body is mounted on the self-leveling scraper holder.

[0025] Optionally, the self-leveling tool holder includes:

[0026] The lifting block is installed at the drive end of the scraper direct drive mechanism;

[0027] An adaptive rotating plate is connected to the lifting block, which rotates freely around a horizontal axis.

[0028] A rotation-limiting baffle is installed on one side of the lifting block and extends to the opposite side of the adaptive rotating plate to restrict the free rotation of the adaptive rotating plate.

[0029] Optionally, the top of the adaptive rotating plate is provided with a rotating plate stop surface, and the bottom surface of the limiting rotating plate is provided with a baffle stop surface extending to the opposite of the rotating plate stop surface.

[0030] When the two stop surfaces are parallel to each other, there is a space between the two stop surfaces to allow the adaptive rotating plate to swing freely around the horizontal axis within a preset angle.

[0031] Optionally, the visual recognition mechanism includes:

[0032] A double-sided camera is located below the screen-printed steel mesh. The top surface has a top shooting port for upward acquisition of the position information of the steel mesh protrusion, and the bottom surface has a bottom shooting port for downward acquisition of the position information of the protruding structure.

[0033] A camera translation drive mechanism, with its drive end connected to the dual-sided camera, is used to drive the dual-sided camera to move horizontally.

[0034] Optionally, the printing platform includes a PCB conveyor line and a conveyor line three-way drive module that is communicatively connected to the double-sided camera to drive the PCB conveyor line to perform XYZ three-way translational motion.

[0035] Optional, also includes:

[0036] A telescopic blocking mechanism is installed at the drive end of the camera translation drive mechanism and is used to extend downward to block the irregularly shaped circuit board on the PCB conveyor line.

[0037] On the other hand, a printing method is provided, performed by any of the aforementioned irregular PCB printing machines, comprising:

[0038] The positioning information of the raised hull of the screen-printed stencil and the raised structure of the irregularly shaped circuit board is obtained through visual positioning.

[0039] This allows the screen-printed stencil and the irregularly shaped circuit board to be attached vertically, and the protruding structure to be accommodated within the stencil protrusion.

[0040] A rotating printing operation is performed on the planar area of ​​the top surface of the screen-printed stencil near the stencil protrusion, along the peripheral contour of the stencil protrusion.

[0041] A linear translation printing operation is performed on the planar area of ​​the top surface of the screen-printed stencil away from the convex hull of the stencil.

[0042] The beneficial effects of this invention are as follows: It provides an irregularly shaped PCB printing machine and printing method. First, an irregularly shaped circuit board with a raised structure on its top surface, to be printed, is placed on the printing platform. The screen printing stencil located above the printing platform has inwardly recessed stencil protrusions on its lower surface at positions corresponding to the raised structures of the irregularly shaped circuit board. The vision recognition mechanism is activated to visually locate the stencil protrusions on the screen printing stencil, obtaining their precise position in space. Subsequently, the rotatable squeegee module located above the screen printing stencil begins operation. On the top surface of the screen printing stencil, under the guidance of the vision recognition mechanism, the movement of the rotatable squeegee module is intelligently configured into two modes:

[0043] When the device moves to a planar area close to the stencil protrusion, the retractable squeegee module uses its rotational degree of freedom to drive the squeegee to rotate around the vertical axis, thereby performing a rotational printing operation along the peripheral contour of the stencil protrusion projected onto the stencil plane in the planar area around the stencil protrusion.

[0044] When the squeegee module moves to a planar area on the top surface of the screen printing stencil that is far from the convex hull of the stencil, it mainly utilizes its translational freedom to perform conventional linear translational printing operations.

[0045] The irregular PCB printing machine provided by this invention creatively introduces a rotational degree of freedom (rotation around a vertical axis) to the squeegee module, combined with a translational degree of freedom. This allows the squeegee to flexibly "bypass" the projection area of ​​the squeegee's protrusion on the plane through rotational motion when it travels to the planar area near the protrusion on the silkscreen stencil. Its movement trajectory can closely follow the edge contour of the protrusion, thereby ensuring that solder paste can be completely and evenly squeegeed on the circuit board area around the protrusion structure. This effectively avoids the printing blanks or interference problems caused by traditional pure translational squeegees that cannot avoid the projection area of ​​the protrusion, significantly improving the printing adaptability and printing quality of irregular PCBs.

[0046] Therefore, the irregular PCB printing machine and printing method provided by the present invention can solve the problem that existing printing equipment cannot perform printing operations on irregular circuit boards with raised structures. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 A schematic diagram of the irregular PCB printing machine provided in the embodiment;

[0049] Figure 2 This is a schematic diagram of the structure of the bypassable scraper module provided in the embodiment;

[0050] Figure 3 A schematic diagram of the rotating platform provided in the embodiment;

[0051] Figure 4 A schematic diagram of the self-leveling tool holder provided for the embodiment;

[0052] Figure 5 A front view of an irregularly shaped PCB printer provided for an embodiment;

[0053] Figure 6 for Figure 5 A schematic diagram from the perspective of point A;

[0054] Figure 7 This is a schematic diagram showing the layout of the bypassable scraper module, the vision recognition mechanism, and the PCB conveyor line provided in the embodiment.

[0055] In the picture:

[0056] 100. Screen-printed stencil; 100a. Embossed stencil;

[0057] 200. Irregularly shaped circuit board; 200a. Raised structure;

[0058] 300, Printing platform; 300a, PCB conveyor line; 300b, Three-way drive module for conveyor line;

[0059] 400, Visual recognition mechanism; 400a, Dual-sided camera; 400b, Camera translation drive mechanism;

[0060] 500. Retractable scraper module;

[0061] 600. Telescopic stop mechanism;

[0062] 1. Rotating platform; 101. Upper platform rotating plate; 102. Lower platform rotating plate; 103. Platform connecting column;

[0063] 2. Platform rotary drive mechanism;

[0064] 3. Scraper assembly; 301. Scraper direct drive mechanism; 302. Self-leveling blade holder; 3021. Lifting block; 3022. Adaptive rotating plate; 30221. Rotating plate stop surface; 3023. Rotation limiting baffle; 30231. Baffle stop surface; 3024. Rotary bearing; 303. Scraper body;

[0065] 4. Translation drive module. Detailed Implementation

[0066] In this invention, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of the invention. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this invention, as long as there is no technical contradiction or conflict, the technical features mentioned in each embodiment can be combined in any way to form a corresponding implementable technical solution.

[0067] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit the invention.

[0068] In the description of this invention, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " generally indicates that the preceding and following objects have an "or" logical relationship.

[0069] In this invention, terms such as “first” and “second” are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy, or order between these entities or operations.

[0070] Without further limitations, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this invention is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0071] Similar to the understanding in the Examination Guidelines, in this invention, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments of this invention, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0072] In the description of the embodiments of the present invention, the spatial related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of the present invention or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0073] Unless otherwise explicitly stated or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this invention, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral arrangement; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this invention according to the specific circumstances.

[0074] The direct drive mechanism in this invention can be a linear motor, a cylinder, a hydraulic cylinder, or a motor lead screw and slider assembly, etc.; the rotary drive mechanism can be a servo motor, a stepper motor, or a rotary cylinder, etc.

[0075] Example 1

[0076] See Figures 1-7 This embodiment provides an irregularly shaped PCB printing machine, suitable for printing on irregularly shaped circuit boards 200 with a raised structure 200a on the top surface, including:

[0077] The printing platform 300 is used to receive the irregularly shaped circuit board 200;

[0078] A screen printing stencil 100 is located above the printing platform 300, and a stencil protrusion 100a is provided at a position corresponding to the protrusion structure 200a of the irregular circuit board 200.

[0079] A visual recognition mechanism 400 is used to perform visual positioning of the steel mesh protrusion 100a;

[0080] The rotatable scraper module 500 is located above the screen printing steel mesh 100 and has at least a translational degree of freedom to move in the horizontal direction and a rotational degree of freedom to rotate about the vertical axis.

[0081] The retractable scraper module 500 is configured as follows:

[0082] Guided by the visual recognition mechanism 400, a rotational printing operation is performed along the periphery of the stencil protrusion 100a in the planar area of ​​the top surface of the screen printing stencil 100 near the stencil protrusion 100a; and a linear translational printing operation is performed in the planar area of ​​the top surface of the screen printing stencil 100 away from the stencil protrusion 100a.

[0083] The specific working process is as follows: First, the irregularly shaped circuit board 200 with a raised structure 200a on its top surface, to be printed, is placed on the printing platform 300. The screen printing stencil 100, located above the printing platform 300, has an inwardly recessed stencil protrusion 100a on its lower surface at a position corresponding to the raised structure 200a of the irregularly shaped circuit board 200. The visual recognition mechanism 400 is activated to visually locate the stencil protrusion 100a on the screen printing stencil 100, obtaining its precise position in space. Subsequently, the rotatable squeegee module 500 located above the screen printing stencil 100 begins to work. On the top surface of the screen printing stencil 100, under the guidance of the visual recognition mechanism 400, the movement of the rotatable squeegee module 500 is intelligently configured into two modes:

[0084] When the squeegee module 500 moves to a planar area close to the stencil protrusion 100a, it uses its rotational degree of freedom to drive the squeegee to rotate around the vertical axis, thereby performing a rotational printing operation along the peripheral contour of the stencil protrusion 100a projected onto the stencil plane in the planar area around the stencil protrusion 100a.

[0085] When the squeegee module 500 moves to a planar area on the top surface of the screen printing stencil 100 that is far from the stencil protrusion 100a, it mainly uses its translational degree of freedom to perform conventional linear translational printing operations.

[0086] The irregular PCB printing machine provided by this invention creatively introduces a rotational degree of freedom (rotation around a vertical axis) to the squeegee module, combined with a translational degree of freedom. This allows the squeegee to flexibly "bypass" the projection area of ​​the squeegee protrusion 100a on the plane through rotational motion when it travels to the planar area near the protrusion on the stencil 100. Its movement trajectory can closely follow the edge contour of the protrusion, thereby ensuring that solder paste can be completely and evenly squeegeed on the circuit board area around the protrusion structure 200a. This effectively avoids the printing blanks or interference problems caused by traditional pure translational squeegees that cannot avoid the projection area of ​​the protrusion, significantly improving the printing adaptability and printing quality of irregular PCBs.

[0087] Therefore, the irregular PCB printing machine provided by the present invention can solve the problem that existing printing equipment cannot perform printing operations on irregular circuit boards 200 with raised structures 200a.

[0088] In this embodiment, the retractable scraper module 500 includes:

[0089] Rotating platform 1;

[0090] Platform rotary drive mechanism 2, with its drive end connected to the rotary platform 1, is used to drive the rotary platform 1 to rotate around the vertical axis;

[0091] The scraper assembly 3 is mounted on the rotating platform 1 and rotates with the rotating platform 1 around the vertical axis.

[0092] Translation drive module 4, with its drive end connected to the rotating platform 1, is used to drive the rotating platform 1 to perform translational reciprocating motion.

[0093] For example, the translation drive module 4 can be a unidirectional direct drive mechanism, a bidirectional direct drive mechanism, or a tridirectional direct drive mechanism, etc. This embodiment does not limit this.

[0094] The translation drive module 4, as the main drive unit, is connected to the rotating platform 1 at its drive end. It is responsible for driving the entire rotating platform 1 and its load to perform reciprocating translational motion in the horizontal direction. This is the basis for enabling the squeegee assembly 3 to move over a wide range on the screen printing stencil 100. The squeegee assembly 3, mounted on the rotating platform 1, moves along with it. When circumferential printing is required, the platform rotary drive mechanism 2 is activated, and its drive end directly drives the rotating platform 1 to rotate precisely around the vertical axis. Since the squeegee assembly 3 is fixedly mounted on the rotating platform 1, it will synchronously follow the rotation of the rotating platform 1, thereby achieving rotational circumferential motion on a plane.

[0095] The above structure provides a modular and easily implemented motion decoupling solution for the retractable scraper module 500. By integrating the rotation function onto a separate rotating platform 1, driven by a dedicated platform rotation drive mechanism 2, and then mounting the platform as a whole onto the translation drive module 4, the two degrees of freedom of translation and rotation are clearly separated. This design makes the motion control logic clear, the mechanical structure reliable, and facilitates independent optimization and calibration of rotational and translational accuracy, ensuring the accuracy and stability of the composite motion trajectory.

[0096] Specifically, the rotating platform 1 includes an upper platform rotating plate 101 connected to the drive end of the platform rotating drive mechanism 2, a lower platform rotating plate 102 spaced apart from or even below the upper platform rotating plate 101, and a platform connecting column 103 connecting the upper platform rotating plate 101 and the lower platform rotating plate 102.

[0097] The scraper assembly 3 includes:

[0098] The scraper direct drive mechanism 301 is installed on the side of the lower platform turntable 102 near the upper platform turntable 101, and the drive end protrudes to the bottom of the lower platform turntable 102;

[0099] The self-leveling blade holder 302 is located below the lower platform rotating plate 102 and is connected to the drive end of the scraper direct drive mechanism 301.

[0100] The scraper body 303 is mounted on the self-leveling scraper holder 302.

[0101] The upper platform rotating plate 101 is connected to the drive end of the platform rotary drive mechanism 2, receiving rotational power. The upper platform rotating plate 101 and the lower platform rotating plate 102 are rigidly connected by the platform connecting column 103, thus forming a stable frame-type rotating platform 1, ensuring overall rigidity during rotation. The scraper direct drive mechanism 301 is installed on the top of the lower platform rotating plate 102, but its drive end extends downward through the lower platform rotating plate 102. The self-leveling blade holder 302 is connected to the protruding drive end, and the scraper body 303 is finally installed on the self-leveling blade holder 302. During operation, the platform rotary drive mechanism 2 drives the entire rotating platform 1 to rotate, thereby causing the scraper direct drive mechanism 301, the self-leveling blade holder 302, and the scraper body 303 to revolve together, achieving a circular motion. The squeegee direct drive mechanism 301 can operate independently, driving the self-leveling squeegee holder 302 and the squeegee body 303 to move up and down relative to the rotating platform 1, so as to complete the adhesion and separation of the squeegee to the screen printing steel mesh 100.

[0102] The beneficial effects of this structural design are mainly reflected in two aspects: First, by setting up rotating plates spaced vertically and connecting them with columns, a stable and torsional-resistant rotating frame is formed, improving the structural rigidity and dynamic stability of the rotational motion and reducing vibrations that may occur during high-speed rotation. Second, by installing the scraper direct drive mechanism 301 inside the rotating platform 1, with its drive end extending downwards to connect to the scraper holder, efficient spatial integration and motion decoupling of the scraper lifting drive and rotation drive are achieved. The scraper lifting action is completely controlled by the independent scraper direct drive mechanism 301, without affecting the rotational motion; while the rotational motion is completed by the platform as a whole, without interfering with the scraper's own lifting. The two work together without interfering with each other, making the composite motion control more precise and reliable.

[0103] In this embodiment, the self-leveling tool holder 302 includes:

[0104] The lifting block 3021 is installed at the drive end of the scraper direct drive mechanism 301;

[0105] An adaptive rotating plate 3022 is rotatably connected to the lifting block 3021 about a horizontal rotating axis; for example, the adaptive rotating plate 3022 and the lifting block 3021 are rotatably connected by a rotary bearing 3024.

[0106] A rotation-limiting baffle 3023 is mounted on one side of the lifting block 3021 and extends to the opposite side of the adaptive rotating plate 3022 to restrict the free rotation of the adaptive rotating plate 3022.

[0107] Furthermore, the top of the adaptive rotating plate 3022 is provided with a rotating plate stop surface 30221, and the bottom surface of the limiting rotating plate 3023 is provided with a baffle stop surface 30231 extending to the opposite of the rotating plate stop surface 30221.

[0108] When the two stop surfaces are parallel to each other, there is a space between the two stop surfaces to allow the adaptive rotating plate 3022 to swing freely around the horizontal axis within a preset angle.

[0109] In this embodiment, the working process of the self-leveling tool holder 302 is as follows:

[0110] The drive end of the scraper direct drive mechanism 301 is connected to the lifting block 3021, driving it to perform lifting actions.

[0111] The adaptive rotating plate 3022 is rotatably connected to the lifting block 3021 via a horizontal rotating shaft, which allows the adaptive rotating plate 3022 and the scraper body 303 mounted on it to swing freely around the horizontal rotating shaft within a certain angle.

[0112] The rotation limiting baffle 3023 is fixedly installed on the lifting block 3021, and its side extends to a position opposite to the adaptive rotating plate 3022. In order to achieve precise and reliable limitation of the free swing angle, a rotating plate stop surface 30221 is provided on the top of the adaptive rotating plate 3022, and a baffle stop surface 30231 opposite to it is provided on the bottom surface of the rotation limiting baffle 3023.

[0113] In the initial or theoretically vertical state, the two stop surfaces are parallel to each other and maintain a preset interval. When the scraper operates on the surface of the screen-printed stencil 100, if it encounters slight flatness fluctuations, the adaptive rotating plate 3022 can swing freely around the horizontal axis to perform adaptive leveling, at which time the distance between the two stop surfaces changes. As long as the swing angle is controlled within the preset range, the two stop surfaces will not contact each other, and the adaptive leveling process is smooth and unobstructed. Once the swing angle is too large, the rotating plate stop surface 30221 will contact the baffle stop surface 30231, forming a mechanical hard limit, immediately preventing the adaptive rotating plate 3022 from further flipping. The width of the interval space is preferably designed to be between 0.1mm and 5mm, a range that has been verified in practice. This ensures that the adaptive rotating plate 3022 has sufficient swing space to adapt to the slight unevenness of the screen-printed stencil 100 surface, achieving effective self-leveling, while strictly limiting the maximum swing angle to avoid instability or interference risks caused by excessive flipping.

[0114] The self-leveling blade holder 302 described above has the following advantages: First, the rotatable connection between the adaptive rotating plate 3022 and the lifting block 3021 endows the squeegee with self-leveling capability at the microscopic level, enabling it to conform to the stencil surface in real time, ensuring uniform printing pressure and thus improving the consistency of printing quality. Second, the cooperation between the rotating plate stop surface 30221 and the baffle stop surface 30231, and the interval space between them, provides a precise, reliable, and quantifiable mechanical limit for the self-leveling function. This not only prevents damage to the stencil or the squeegee itself due to excessive rotation of the squeegee posture caused by unexpected circumstances.

[0115] In this embodiment, the visual recognition mechanism 400 includes:

[0116] A double-sided camera 400a is located below the screen-printed steel mesh 100. The top surface has a top shooting port for obtaining the position information of the steel mesh protrusion 100a upwards, and the bottom surface has a bottom shooting port for obtaining the position information of the protruding structure 200a downwards.

[0117] The camera translation drive mechanism 400b has its drive end connected to the double-sided camera 400a and is used to drive the double-sided camera 400a to move horizontally.

[0118] In this invention, "double-sided camera 400a" refers to an industrial vision device in the prior art that has two vision acquisition modules, one upward and one downward. For example, dual-view vision systems commonly used in the SMT field to simultaneously identify components on the front of a PCB board and carrier reference points, or bidirectional inspection cameras in PCB inspection equipment to simultaneously acquire images of the board surface and component pins, are all mature products of this type. Those skilled in the art can directly select commercially available products with double-sided vision functionality, or implement it by integrating two independent industrial cameras back-to-back. The innovation of this invention lies not in the structure of the camera itself, but in its integration with the camera translation drive mechanism 400b and the entire printing system to achieve synchronous or sequential positioning of the "stencil protrusion 100a" and the "protrusion structure 200a". Therefore, its implementation is not dependent on a specific model; any vision module capable of bidirectional image acquisition can be applied to this invention.

[0119] The dual-sided camera 400a is a core sensing component. Its top-side camera aperture faces the screen-printed stencil 100 upwards, capturing the precise position of the stencil protrusion 100a on the bottom surface of the stencil. Its bottom-side camera aperture faces the irregularly shaped circuit board 200 placed on the printing platform 300 downwards, capturing the precise position of the protruding structure 200a on the top surface of the circuit board. The camera translation drive mechanism 400b is connected to the dual-sided camera 400a, driving it to move horizontally, thereby aligning its top and bottom camera apertures above and below the stencil protrusion 100a and the protruding structure 200a, respectively, to complete the positioning and capturing. This achieves efficient and high-precision dual positioning. By using an integrated dual-sided camera 400a in conjunction with a translation drive, the visual coordinates of both the stencil protrusion 100a and the circuit board protrusion structure 200a can be acquired sequentially or simultaneously. This provides a precise and unified coordinate reference for subsequent control of the printing platform 300 for alignment and bonding, as well as for planning the bypass path of the bypassable squeegee module 500, greatly improving alignment accuracy and overall system coordination. Simultaneously, the compact structure reduces the space occupied by the equipment.

[0120] In this embodiment, the printing platform 300 includes a PCB conveyor line 300a and a conveyor line three-way drive module 300b that is communicatively connected to the double-sided camera 400a to drive the PCB conveyor line 300a to move in XYZ three-way translation.

[0121] Furthermore, the irregular PCB printing machine also includes a telescopic stop mechanism 600. The telescopic stop mechanism 600 is mounted on the drive end of the camera translation drive mechanism 400b and is used to extend downward to block the irregular circuit board 200 on the PCB conveyor line 300a.

[0122] The collaborative working process between the printing platform 300 and the visual recognition mechanism 400 is as follows:

[0123] First, the camera translation drive mechanism 400b drives the telescopic stop mechanism 600 to move in front of the predetermined path of the irregularly shaped circuit board 200 on the PCB conveyor line 300a. When the irregularly shaped circuit board 200 is conveyed by the PCB conveyor line 300a to near the printing station, the telescopic stop mechanism 600 extends downward to precisely block and position the irregularly shaped circuit board 200 at the printing station.

[0124] Subsequently, the camera translation drive mechanism 400b drives the dual-sided camera 400a to move, aligning its bottom shooting port with the protruding structure 200a on the circuit board to obtain its position information; simultaneously or subsequently, aligning its top shooting port with the stencil protrusion 100a on the screen-printed stencil 100 to obtain its position information. After completing the visual positioning, the dual-sided camera 400a moves to avoid being positioned further away.

[0125] Next, the three-way drive module 300b of the conveyor line, which is communicatively connected to the dual-sided camera 400a, starts to work. Based on the acquired visual coordinate data, it drives the PCB conveyor line 300a to perform precise X and Y-axis translation, so that the protrusion structure 200a on the circuit board is aligned with the stencil protrusion 100a on the stencil in a planar position. Then, it drives the PCB conveyor line 300a to rise, so that the protrusion structure 200a is embedded in the stencil protrusion 100a and presses the circuit board in preparation for printing.

[0126] Finally, the bypass squeegee module 500 can plan the translation and bypass routes based on the information collected by the double-sided camera 400a to complete the printing operation.

[0127] Generally, lifting and blocking mechanisms used for material blocking are installed on conveyor lines. To adjust the blocking position, an XY bidirectional adjustment platform needs to be installed at the bottom of the lifting and blocking mechanism. In this embodiment, since the camera translation drive mechanism 400b is already installed on the bottom surface of the steel mesh, the telescopic blocking mechanism 600 is installed on the camera translation drive mechanism 400b, allowing the camera translation drive mechanism 400b to be reused for material blocking, thus reducing equipment costs.

[0128] The printing platform 300 and vision recognition mechanism 400 provided in this embodiment achieve fully automated and high-precision closed-loop control of the entire process, including positioning, material blocking, alignment, and bonding. Firstly, by integrating the telescopic material blocking mechanism 600 onto the camera translation drive mechanism 400b, a single drive system is creatively reused to achieve precise material blocking at adjustable positions, eliminating the need for a separate XY material blocking drive module, significantly simplifying the mechanical structure and reducing hardware costs. Secondly, the double-sided camera 400a and the three-way drive module 300b of the conveyor line communicate and link based on visual information, forming a visual feedback closed loop. This fully automates the entire process from coarse positioning of the circuit board, visual fine positioning to final motion alignment and bonding, with accuracy guaranteed by the vision system, completely eliminating errors from manual intervention and greatly improving the printing accuracy and production cycle time for irregularly shaped PCBs. Thirdly, these components are functionally closely integrated and share data, forming a highly efficient and collaborative subsystem, fundamentally improving the adaptability, processing consistency, and reliability of the entire equipment for irregularly shaped circuit boards 200.

[0129] Example 2

[0130] This embodiment provides a printing method, executed by any of the irregularly shaped PCB printing machines provided in Embodiment 1, which includes the following steps:

[0131] S10: Obtain the positioning information of the stencil protrusion 100a of the screen-printed stencil 100 and the protrusion structure 200a of the irregular circuit board 200 through visual positioning.

[0132] S20: The screen printing stencil 100 and the irregular circuit board 200 are attached vertically, and the protruding structure 200a is accommodated in the stencil protrusion 100a;

[0133] S30: A rotating printing operation is performed along the periphery of the stencil protrusion 100a in the planar area near the top surface of the screen printing stencil 100.

[0134] S40: Perform a linear translation printing operation on the planar area of ​​the top surface of the screen printing stencil 100 away from the stencil protrusion 100a.

[0135] The printing method provided in this embodiment is a procedural manifestation of the collaborative operation of various functional modules of the irregular PCB printing machine. The method begins with the action of the vision recognition mechanism 400: the camera translation drive mechanism 400b first drives the double-sided camera 400a to move, so that its bottom shooting port is aligned with the irregular circuit board 200 on the printing platform 300, and captures the image and position coordinates of its raised structure 200a; subsequently, the same drive mechanism drives the double-sided camera 400a to move, so that its top shooting port is aligned with the screen printing stencil 100, and captures the image and position coordinates of its stencil protrusion 100a, thereby completing high-precision dual vision positioning.

[0136] Next, the positioning data is sent to the three-way drive module 300b of the conveyor line. This module drives the PCB conveyor line 300a to perform precise X and Y-axis translation, achieving initial alignment of the planar position, and then performs a Z-axis upward movement. This action causes the irregularly shaped circuit board 200 to be lifted as a whole, and the protrusion structure 200a on it is precisely embedded into the stencil protrusion 100a of the screen printing stencil 100 until the circuit board and the bottom surface of the stencil are tightly attached, preparing for printing.

[0137] The core printing operation is performed by the retractable squeegee module 500. The control system plans a composite motion path for the squeegee based on the contour coordinates of the stencil protrusion 100a pre-acquired by the vision system. In the flat area on the top surface of the stencil away from the protrusion, the translation drive module 4 drives the entire module to perform conventional linear reciprocating squeegee printing. When the squeegee needs to process the area surrounding the protrusion, the platform rotary drive mechanism 2 is activated, driving the rotating platform 1 to rotate and revolve the squeegee assembly 3 along the peripheral contour of the stencil protrusion 100a. During this process, if the stencil surface exhibits a slight tilt due to the presence of the protrusion, the self-leveling blade holder 302 in the squeegee assembly 3 can adjust the posture of the squeegee body 303 in real time to ensure that the squeegee blade edge always maintains ideal contact with the stencil surface.

[0138] This printing method transforms the structural innovation of the irregular PCB printer into a stable and programmable process solution. Through the sequential and data-driven linkage of the vision recognition mechanism 400, the three-way drive module 300b of the conveyor line, and the squeegee module 500, full automation of the entire process—from automatic feeding and positioning, high-precision alignment and bonding, to intelligent zone printing—is achieved. This method fundamentally solves the problem of solder paste printing around the raised areas of irregular PCBs, ensuring the integrity and uniformity of the printed pattern, and significantly improving production yield and efficiency.

[0139] Based on Example 1, features not explained in this example will be explained using the methods described in Example 1, and will not be repeated here.

[0140] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A shaped PCB printing machine, suitable for printing on shaped circuit boards (200) with a raised structure (200a) on the top surface, characterized in that, include: A printing platform (300) is used to receive the irregularly shaped circuit board (200). A screen printing stencil (100) is located above the printing platform (300) and has a stencil protrusion (100a) at a position corresponding to the protrusion structure (200a) of the irregular circuit board (200). A visual recognition mechanism (400) is used to visually locate the steel mesh protrusion (100a); The retractable scraper module (500) is located above the screen printing steel mesh (100) and has at least a translational degree of freedom to translate in the horizontal direction and a rotational degree of freedom to rotate about the vertical axis. The retractable scraper module (500) is configured as follows: Guided by the visual recognition mechanism (400), a rotational printing operation is performed along the periphery of the stencil protrusion (100a) in the planar area of ​​the top surface of the screen printing stencil (100) near the stencil protrusion (100a); and a linear translation printing operation is performed in the planar area of ​​the top surface of the screen printing stencil (100) away from the stencil protrusion (100a).

2. The irregular PCB printing machine according to claim 1, characterized in that, The retractable scraper module (500) includes: Rotating platform (1); The platform rotary drive mechanism (2) has its drive end connected to the rotary platform (1) and is used to drive the rotary platform (1) to rotate around the vertical axis. The scraper assembly (3) is mounted on the rotating platform (1) and rotates around the vertical axis with the rotating platform (1); The translation drive module (4) is connected to the rotating platform (1) at its drive end and is used to drive the rotating platform (1) to perform translational reciprocating motion.

3. The irregular PCB printing machine according to claim 2, characterized in that, The rotating platform (1) includes an upper platform rotating plate (101) connected to the drive end of the platform rotating drive mechanism (2), a lower platform rotating plate (102) spaced apart from or below the upper platform rotating plate (101), and a platform connecting column (103) connecting the upper platform rotating plate (101) and the lower platform rotating plate (102).

4. The irregular PCB printing machine according to claim 3, characterized in that, The scraper assembly (3) includes: The scraper direct drive mechanism (301) is installed on the side of the lower platform turntable (102) near the upper platform turntable (101), and the drive end protrudes to the bottom of the lower platform turntable (102); The self-leveling blade holder (302) is located below the lower platform turntable (102) and connected to the drive end of the scraper direct drive mechanism (301); The scraper body (303) is mounted on the self-leveling scraper holder (302).

5. The irregular PCB printing machine according to claim 4, characterized in that, The self-leveling tool holder (302) includes: The lifting block (3021) is installed at the drive end of the scraper direct drive mechanism (301); The adaptive rotating plate (3022) is freely rotatable to the lifting block (3021) around a horizontal rotating axis; A rotation-limiting baffle (3023) is mounted on one side of the lifting block (3021) and extends to the opposite side of the adaptive rotating plate (3022) to restrict the free rotation of the adaptive rotating plate (3022).

6. The irregular PCB printing machine according to claim 5, characterized in that, The top of the adaptive rotating plate (3022) is provided with a rotating plate stop surface (30221), and the bottom surface of the limiting rotating plate (3023) is provided with a baffle stop surface (30231) extending to the opposite of the rotating plate stop surface (30221). When the two stop surfaces are parallel to each other, there is a space between the two stop surfaces to allow the adaptive rotating plate (3022) to swing freely around the horizontal axis within a preset angle.

7. The irregular PCB printing machine according to claim 1, characterized in that, The visual recognition mechanism (400) includes: A double-sided camera (400a) is located below the screen-printed steel mesh (100). The top surface has a top shooting port for upward acquisition of the position information of the steel mesh protrusion (100a), and the bottom surface has a bottom shooting port for downward acquisition of the position information of the protruding structure (200a). A camera translation drive mechanism (400b) is connected to the dual-sided camera (400a) at its drive end, and is used to drive the dual-sided camera (400a) to move horizontally.

8. The irregular PCB printing machine according to claim 7, characterized in that, The printing platform (300) includes a PCB conveyor line (300a) and a conveyor line three-way drive module (300b) that is communicatively connected to the double-sided camera (400a) to drive the PCB conveyor line (300a) to move in XYZ three-way translation.

9. The irregular PCB printing machine according to claim 8, characterized in that, Also includes: A telescopic stop mechanism (600) is installed at the drive end of the camera translation drive mechanism (400b) and is used to extend downward to block the irregular circuit board (200) on the PCB conveyor line (300a).

10. A printing method, performed by the irregular PCB printing machine according to any one of claims 1-9, characterized in that, include: Positioning information of the stencil protrusion (100a) of the screen-printed stencil (100) and the protrusion structure (200a) of the irregularly shaped circuit board (200) is obtained through visual positioning. This allows the screen-printed stencil (100) and the irregularly shaped circuit board (200) to be attached vertically, and the protruding structure (200a) to be housed within the stencil protrusion (100a); A rotating printing operation is performed along the periphery of the stencil protrusion (100a) in the planar area of ​​the top surface of the screen printing stencil (100). A linear translation printing operation is performed on the planar area of ​​the top surface of the screen printing stencil (100) away from the stencil protrusion (100a).

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