Efficient and energy-saving SMT printing jig

Abstract

The invention relates to the technical field of manufacturing of electrical components, in particular to an efficient and energy-saving SMT printing jig which comprises a workbench, and coordinate points distributed in the radial direction X and the axial direction Y are arranged on the workbench face. A supporting mechanism is arranged on the top end face of the workbench. A cleaning piece used for cleaning the steel mesh periodically is further arranged below the workbench. The upper part of the back plate is connected with a steel mesh through a first driver and is positioned above the workbench; a scraper and a liquid spraying pipe are further connected to the back plate and located above the steel mesh through a second driver. The second driver is configured to drive the scraper and the liquid spraying pipe to integrally move left and right and move front and back, and can complete height adjusting operation that the scraper is far away from and close to the steel mesh; a cavity is formed in the lower part of the back plate; a heating barrel is arranged in the cavity; and a stirring piece is further arranged in the heating barrel to keep the fluidity of the solder paste. The optimized structure adopts an integrated design, and the purposes of intelligently adjusting to adapt to multi-size PCB processing and improving the PCB operation efficiency and quality are achieved.

Description

Technical Field

[0001] This invention relates to the field of printed circuit and electrical component manufacturing technology, specifically to a high-efficiency and energy-saving SMT printing fixture. Background Technology

[0002] In products such as smartphones, wearable devices, and automotive electronics, precision circuit boards serve as the "brain" of the device. The core technology for precisely "placed" these tiny components on the circuit boards is surface mount technology (SMT). As a core process in electronics manufacturing, SMT determines the performance, reliability, and production efficiency of electronic products. SMT printing primarily focuses on solder paste printing, which involves precisely printing a paste-like solder paste onto the PCB pads using a stencil. The stencil aperture accuracy must reach ±0.01mm, and the solder paste thickness is monitored in real time using a laser sensor. This step is like "micro-sculpture art on the circuit board," directly affecting the reliability of subsequent soldering. However, existing SMT printing fixtures have simple structures, limited functions, and unsatisfactory performance.

[0003] A search of the publicly available prior art "CN108601240B, An SMT Printing Fixture" describes it as "including a machine body, a fixture body, an FR4 board, a PCB circuit board, an SMT printing stencil, and a squeegee assembly. The squeegee assembly includes a high-pressure solder storage box, a squeegee drive assembly, a squeegee recovery drive assembly, a solder paste mixing assembly, and a mixing box. The squeegee drive assembly includes a squeegee cylinder, a squeegee drive connector, and a squeegee body. The squeegee recovery drive assembly includes a squeegee cylinder, a squeegee drive connector, and a squeegee body." The beneficial effects of this invention are: it overcomes a series of shortcomings caused by manual solder paste mixing in traditional technology, and improves product production efficiency by adopting automatic solder paste mixing and automatic solder paste dispensing; moreover, it can recycle and reuse excess solder paste.

[0004] The existing SMT fixtures still suffer from the following technical problems: First, they lack support and adjustment structures, making them unsuitable for complex and diverse support environments. Without a stable horizontal support plane, PCB deformation is highly likely. Furthermore, the existing SMT fixtures cannot efficiently adapt to the varying sizes of different PCBs, hindering high-quality processing. Second, they lack effective stencil cleaning. In SMT printing, the frequency of stencil cleaning directly impacts solder paste printing quality and product yield. Traditional stencil cleaning methods often rely on manual labor or other independent cleaning equipment, which is cumbersome and ineffective. It is difficult to achieve both efficient PCB printing and high-quality processing while simultaneously improving stencil cleaning efficiency. Third, solder paste in non-use states is generally stored in an environment with certain refrigeration conditions. That is, solder paste needs to be thawed to room temperature before it can be used effectively. However, the traditional solder paste thawing method is not very effective and cannot achieve integrated structure, high efficiency and energy saving by utilizing waste heat to treat the solder paste. This results in low work efficiency and high energy consumption. Therefore, there is an urgent need for a high-efficiency and energy-saving SMT printing fixture. Summary of the Invention

[0005] To address the shortcomings and deficiencies of existing SMT printing technologies, this invention provides an efficient and energy-saving SMT printing fixture with an optimized integrated design, intelligent adjustment to adapt to multi-size PCBs, and improved PCB manufacturing efficiency and quality.

[0006] The present invention achieves the above objectives by adopting the following technical solution: A high-efficiency and energy-saving SMT printing fixture includes a worktable with horizontally distributed left and right sides, and coordinate points distributed radially (X) and axially (Y) on the worktable surface. A support mechanism is located on the top surface of the worktable, used for supporting and positioning PCBs of different specifications, models, and sizes, and providing board surface error recognition and alarm functions. A cleaning device for periodically cleaning the stencil is also located below the worktable. A backplate is located at the rear of the worktable, and a control panel is located on the right side of the backplate. The control panel is connected to a controller, which has functions of program programming, module embedding, signal transmission, and command control. A stencil is also connected to the upper part of the backplate, located above the worktable, via a first drive to move the stencil left and right. The device is movable and can move back and forth; a second calibration point is provided on the stencil; a scraper and a spray pipe are connected to the back plate and above the stencil via a second drive, with sufficient distance maintained between the scraper and the spray pipe; the second drive is configured to move the scraper and spray pipe as a whole left and right and back and forth, and can adjust the height of the scraper moving away from or closer to the stencil; a cavity is provided at the bottom of the back plate; a heating tank is provided in the cavity, and a resistance wire and a temperature probe are provided on the side wall of the heating tank, with the resistance wire and the temperature probe electrically connected; a stirring element is also provided in the heating tank to maintain the fluidity of the solder paste; a liquid pump is provided on one side of the heating tank, and one end of the liquid pump is connected to the spray pipe via a liquid delivery pipe, which is long enough and also equipped with an electromagnetic flow control valve.

[0007] As a preferred technical solution: a leveling component is also provided at the bottom of the workbench. The leveling component includes an indicator light, a level detection sensor, and a support foot. The indicator light is located on the front of the workbench and includes red and green colors. The level detection sensor is located on the bottom surface of the workbench and is electrically connected to the indicator light. The support foot is mainly composed of a rubber protrusion and a connecting rod located at the center of the rubber protrusion and vertically distributed. The connecting rod is connected to the bottom surface of the workbench by a thread.

[0008] A further preferred technical solution: The support mechanism includes a base plate, guide rods, and cylinders; the base plates are horizontally distributed, with four plates positioned at the four corners. The upper surface of each base plate is also provided with insertion posts for inserting into PCB board holes. When the four base plates are closed, the four insertion posts are arranged in a square. The left front base plate is fixedly mounted on the worktable. The left front base plate is connected to the right front base plate and the left rear base plate via cylinders. The right rear base plate is slidably connected to the left rear base plate and the right front base plate via guide rods. The left front base plate also has a first calibration point located at the (X0, Y0) coordinate point, and the first calibration point corresponds to the position of the insertion post on the base plate. The surface of the left front base plate also has a camera and a voice alarm connected to the camera.

[0009] A further preferred technical solution: A guide component is provided between the right front substrate and the worktable. The guide component includes a guide strip and a guide groove. The guide strip is disposed on the right front substrate, and the guide groove is opened on the worktable. The guide strip and the guide groove are matched and installed. The structure between the left rear substrate and the worktable is the same as the structure between the right front substrate and the worktable.

[0010] A further preferred technical solution: The cleaning component includes a cleaning chamber, a rotating shaft, a rotating frame, and an ultrasonic generator; the cleaning chamber is located at the bottom of the workbench and has a door on one side; the rotating shaft is vertically arranged in the cleaning chamber and has a rotating motor connected to its bottom end; the rotating frame is located on the rotating shaft and has a rectangular frame structure, with a mounting groove on one side for fitting and installing a steel mesh; the ultrasonic generator is located inside the cleaning chamber.

[0011] A further preferred technical solution: The first drive includes a first motor, a first lead screw, a first auxiliary rod, a first mounting base, a first electric push rod, and a mounting plate; the first motor is mounted on the back plate via a bracket, the first lead screw is rotatably mounted between the left and right side walls of the back plate and connected to the first motor; the first auxiliary rod is mounted on the back plate and is parallel to the first lead screw; the first mounting base is mounted on the first lead screw and the first auxiliary rod, and is threadedly connected to the first lead screw and slidably connected to the first auxiliary rod; the first electric push rod is distributed front and rear on the first mounting base, and its other end is connected to the mounting plate.

[0012] A further preferred technical solution: a telescopic rod is provided between the mounting plate and the first mounting seat; the mounting plate is also provided with a groove adapted for the installation of the steel mesh, and is fixed by electromagnet.

[0013] A further preferred technical solution: The second drive includes a second lead screw, a second motor, a second auxiliary rod, a second mounting base, a second electric push rod, and a carrier plate; the second lead screw is rotatably mounted on the back plate and parallel to the first lead screw; the second motor is fixedly mounted on the side wall of the back plate via a bracket and connected to the second lead screw; the second auxiliary rod is mounted on the back plate and parallel to the second lead screw; the second mounting base is threaded to the second lead screw and slidably connected to the second auxiliary rod; one end of the second electric push rod is mounted on the second mounting base, and the other end is connected to the carrier plate; a stretchable connecting arm is also provided between the carrier plate and the second mounting base; the carrier plate is connected to the scraper via a third electric push rod; the spray pipes are vertically distributed on the carrier plate.

[0014] A further preferred technical solution: the stirring component includes a stirring motor, a stirring shaft, and stirring rods; the stirring motor is located at the bottom of the heating tank, the stirring shaft is vertically distributed in the heating tank and connected to the stirring motor; the stirring rods are multiple rods arranged on the stirring shaft, and the multiple stirring rods distributed from top to bottom have a gradually increasing trend.

[0015] A further preferred technical solution: A storage chamber is provided above the heating barrel, and the storage chamber is connected to the heating barrel through an exhaust pipe; the storage chamber is inclined, and one side is connected to the feed pipe, and the other side is connected to the heating barrel through an outlet pipe; electromagnetic switch valves are provided on the exhaust pipe, feed pipe, and outlet pipe.

[0016] The advantages of this invention compared to existing technologies are as follows: This invention optimizes the structure and upgrades the design, employing an integrated design to achieve adaptive adjustment and positioning of the PCB and alignment of the stencil, greatly improving the efficiency of SMT printing. Intelligent adjustment adapts to various PCB sizes and ensures diverse horizontal support conditions, further guaranteeing the stability of the PCB processing foundation and providing strong support for further improving SMT processing quality. Simultaneously, the use of a camera and voice alarm prevents careless placement of the PCB board by workers, avoiding accidents during SMT processing and ensuring the quality and safety of SMT printing. This invention further optimizes the stencil installation, disassembly, and processing structure, improving the cleaning quality and convenience of the stencil, optimizing the solder paste addition method and usage structure, utilizing waste heat, saving resources, reducing energy consumption, and further improving the quality and efficiency of SMT printing. Attached Figure Description

[0017] 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.

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the structure of the worktable of the present invention; Figure 3 This is a distribution diagram of the substrate of the present invention; Figure 4 This is a structural diagram of the guide component of the present invention; Figure 5 This is a schematic diagram of the structure of the first drive of the present invention; Figure 6 This is a three-dimensional structural view of the second drive mechanism of the present invention; Figure 7This is a schematic diagram of the cleaning component of the present invention; Figure 8 This is a partial perspective view of the cleaning component of the present invention; Figure 9 This is a schematic diagram of the heating barrel of the present invention; Figure 10 This is a three-dimensional structural view of the stirring component of the present invention; Figure 11 This is a schematic diagram of the leveling component in Embodiment 2 of the present invention.

[0019] In the diagram: 1. Workbench; 11. Coordinate point; 2. Support mechanism; 21. Base plate; 22. Guide rod; 23. Cylinder; 24. Insertion post; 25. First calibration point; 26. Camera; 27. Voice alarm; 3. Cleaning component; 31. Cleaning chamber; 32. Rotating shaft; 33. Rotating frame; 34. Ultrasonic generator; 35. Box door; 36. Rotating motor; 37. Mounting slot; 4. Back plate; 41. Controllable panel; 42. Controller; 43. Cavity; 44. Storage chamber; 45. Exhaust pipe; 46. Feed pipe; 47. Discharge pipe; 48. Electromagnetic switch valve; 5. First drive; 51. First motor; 52. First lead screw; 53. First auxiliary rod; 54. First mounting base; 55. First electric push rod; 56. Mounting plate; 57. Telescopic rod; 58. Groove; 59. Electromagnet; 6. Steel mesh; 61. Second calibration point; 7. Second drive; 71. Second lead screw; 72. Second motor; 73. Second auxiliary rod; 74. Second mounting base; 75. Second electric push rod; 76. Carrier plate; 77. Connecting arm; 78. Third electric push rod; 8. Scraper; 9. Spray pipe; 10. Heating tank; 101. Resistance wire; 102. Temperature probe; 103. Stirring component; 104. Liquid pump; 105. Infusion pipe; 106. Electromagnetic flow control valve; 107. Stirring motor; 108. Stirring shaft; 109. Stirring rod; 11. Leveling component; 111. Indicator light; 112. Horizontal detection sensor; 113. Support foot; 114. Rubber protrusion; 115. Connecting rod; 12. Guide component; 121. Guide strip; 122. Guide groove. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that, in specific embodiments of the present invention, relational 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 relationship or order between these entities or operations. Furthermore, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, the use of phrases such as "comprising one" to define an element does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0022] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," and "equipped" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; or they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] Example 1: As Figures 1 to 10 As shown: A high-efficiency and energy-saving SMT printing fixture includes a worktable 1, which is horizontally distributed left and right, and has multiple coordinate points 11 distributed radially (X) and axially (Y) on its surface; specifically as follows... Figure 2 As shown: This means that a Cartesian coordinate system is constructed by setting XY coordinates on the surface of the workbench 1, using each coordinate point 11 as the positioning basis to form an adaptable positioning support for PCBs of different sizes. In a preferred embodiment, a support mechanism 2 is provided on the top surface of the workbench 1. The support mechanism 2 is used for supporting and positioning PCBs of different specifications and sizes, and provides board surface error recognition and alarm functions. Specifically, as... Figure 3 As shown: The support mechanism 2 includes a base plate 21, a guide rod 22, and a cylinder 23. The base plates 21 are horizontally distributed, with four plates positioned at the four corners. The upper surface of each base plate 21 is also provided with insertion posts 24 for inserting into PCB board holes. The insertion posts 24 are mainly used for inserting into the holes on the PCB board surface. When the four base plates 21 are closed, the four insertion posts 24 are arranged in a square pattern. Specifically, as shown in the figure, the insertion post 24 of the left front base plate 21 is located at the left front corner of the base plate 21, and the insertion post 24 of the right front base plate 21 is located at the right front corner of the base plate 21. The left front base plate 21 is fixedly mounted on the worktable 1; this arrangement is intended to provide a support origin and positioning reference.

[0024] like Figure 2 and Figure 3 As shown: the left front substrate 21 is connected to the right front substrate 21 and the left rear substrate 21 via cylinders 23. This arrangement allows for adaptive adjustment to PCBs of different sizes by moving the corresponding substrates 21 through the extension and retraction of the cylinders 23. The right rear substrate 21 is slidably connected to the left rear substrate 21 and the right front substrate 21 via guide rods 22, which are extendable and retractable. This arrangement provides good support and guidance. Figure 4 As shown: The left front substrate 21 is also provided with a first calibration point 25, which is located at the (X0, Y0) coordinate point 11 and corresponds to the position of the insertion post 24 on the substrate 21. With this setting, the first calibration point 25 is the origin of the XY rectangular coordinate system. The cylinder 23 is connected to the controller 42, and automated control can be achieved through program programming. The specific working principle is that the operator embeds or programs the function program module in advance, inputs the coordinate point 11 of the XY rectangular coordinate system into it, and then when the PCB is placed and installed, only the size parameters of the current batch of PCBs need to be input. The controller 42 can give commands and transmit signals to the cylinder 23, so that the cylinder 23 extends to a preset length, driving the right front substrate 21 to move and adjust in the X direction and the left rear substrate 21 to move and adjust in the Y direction, thereby quickly realizing the installation foundation with size positioning. The corresponding staff only need to align the corner holes of the PCB with the plug pins 24 for installation. The operation is simple, time-saving and labor-saving, avoiding the time-consuming and labor-intensive manual installation, measurement and fastening positioning operations of existing technologies. It improves stability, has good adaptability and also improves the consistency of SMT printing and processing.

[0025] like Figure 3As shown: In a preferred embodiment, the left front substrate 21 is further equipped with a camera 26 and a voice alarm 27 connected to the camera 26. This arrangement aims to solve the problem that existing SMT printing fixtures lack PCB board surface recognition and have a low level of intelligent processing, and to address the issue of errors easily occurring during traditional manual PCB board placement, leading to safety accidents in subsequent processing. The camera 26 is connected to the controller 42 for signal transmission. The controller 42 pre-sets a correct PCB board image. When the camera 26 detects the correct image, that is, when the current PCB board is correctly placed, the voice alarm 27 does not operate. When the camera 26 does not detect the correct image, that is, when the current PCB board is incorrectly placed (placed backwards), the voice alarm 27 operates, repeatedly playing the prompt "Alarm, incorrect position, please replay." This greatly improves the stability and accuracy of the SMT printing process, further improving the quality of PCB board processing. In a preferred alternative embodiment, the camera 26 and the voice alarm 27 can also be embedded in the worktable, primarily to achieve identification of the front and back of the PCB board.

[0026] like Figure 4 As shown: In a preferred embodiment, a guide member 12 is further provided between the right front substrate 21 and the worktable 1, wherein the guide member 12 includes a guide strip 121 and a guide groove 122. The guide strip 121 is disposed on the right front substrate 21 and can be fixed by welding. The guide groove 122 is formed in the worktable 1, and the guide strip 121 and the guide groove 122 are matched and installed. The structure between the left rear substrate 21 and the worktable 1 is the same as the structure between the right front substrate 21 and the worktable 1. The purpose of this arrangement is to provide a good guiding foundation for the movable substrate 21, providing favorable conditions for subsequent processing of PCBs of different sizes.

[0027] like Figure 1 and Figure 7 As shown: In a preferred embodiment, a cleaning component 3 for periodically cleaning the steel mesh 6 is also provided below the workbench 1. Specifically, the cleaning component 3 includes a cleaning chamber 31, a rotating shaft 32, a rotating frame 33, and an ultrasonic generator 34. The cleaning chamber 31 is located at the lower part of the workbench 1, and has a door 35 on one side; this arrangement allows for opening and closing. The cleaning chamber 31 is filled with cleaning fluid. The rotating shaft 32 is vertically arranged in the cleaning chamber 31, and its bottom end is connected to a rotating motor 36; the rotating motor 36 is a servo-controlled motor. The rotating frame 33 is located on the rotating shaft 32 and has a rectangular frame structure. One side of the rotating frame 33 has a mounting groove 37 for fitting and installing the steel mesh 6. This arrangement allows the steel mesh 6 to be vertically fitted and installed in the mounting groove 37, forming a snap-fit ​​structure. See details below. Figure 8The structure is shown. The ultrasonic generator 34 is located inside the cleaning chamber 31 and is also connected to the controller 42, and can be operated via a controllable panel 41. The specific working principle is as follows: after placing the stencil 6 in the mounting slot 37, the operator turns on the rotating motor 36 and the ultrasonic generator 34. The starting of the rotating motor 36 drives the rotating shaft 32 to rotate synchronously, which in turn drives the rotating frame 33 and the stencil 6 to perform a circular motion. The cleaning effect of the ultrasonic waves is utilized synchronously to complete the cleaning of the stencil 6 during the rotation. During this process, the rotating motor 36 can operate in both forward and reverse directions. In a preferred embodiment, a nano-coating can be applied to the stencil 6 to extend the number of uses and lifespan under periodic stencil 6 cleaning operations. This invention further optimizes and upgrades the structure of the workbench 1, changing the traditional stencil 6 cleaning method with an integrated design that is simple, convenient, and quick to operate. Under normal production conditions, cleaning is performed every 4-8 hours of printing. Cleaning can also be performed after 500-1000 printing cycles. It is worth noting that cleaning is mandatory when changing the PCB product model.

[0028] like Figure 1 As shown: In a preferred embodiment, a back plate 4 is provided on the rear side of the workbench 1. The bottom end of the back plate 4 is flush with the bottom end of the workbench 1, and the top end is higher than the top surface of the workbench 1. The workbench 1 and the back plate 4 can be fixed together by welding. A controllable panel 41 is provided on the right side of the back plate 4. The controllable panel 41 is connected to a controller 42. Specifically, the controller 42 is located in the upper inner cavity of the back plate 4 and is a programmable intelligent controller 42. The controller 42 has functions of program programming, module embedding, signal transmission and command control. The working principle of the program programming of the controller 42 is common knowledge to those skilled in the art, and since this invention mainly protects the mechanical structure, it will not be described in detail. A stencil 6 is also connected to the upper part of the back plate 4 and above the workbench 1 through a first drive 5, so that the stencil 6 can move left and right and back and forth. The purpose of this setting is that, for SMT printing operations of PCBs of different specifications and models, after the basic positioning of the PCB, the stencil 6 is automatically adjusted to achieve precise coverage.

[0029] like Figure 5As shown: The first drive 5 includes a first motor 51, a first lead screw 52, ​​a first auxiliary rod 53, a first mounting base 54, a first electric push rod 55, and a mounting plate 56. The first motor 51 is mounted on the back plate 4 via a bracket, and the first motor 51 is also a servo-controlled motor. The first lead screw 52 is rotatably mounted between the left and right side walls of the back plate 4 and connected to the first motor 51. The first motor 51 drives the first lead screw 52 to rotate. The first auxiliary rod 53 is mounted on the back plate 4 and is parallel to the first lead screw 52; this arrangement serves as a guide and auxiliary function. The first mounting base 54 is mounted on the first lead screw 52 and the first auxiliary rod 53, maintaining a threaded rotational connection with the first lead screw 52 and a sliding connection with the first auxiliary rod 53; this arrangement aims to form a "lead screw and nut" structure through a basic and relatively simple structural design, ensuring stable movement adjustment and thus enabling the reciprocating movement of the first mounting base 54. The first electric push rod 55 is distributed front and rear on the first mounting base 54, with its other end connected to the mounting plate 56. The mounting plate 56 serves as the carrier for connecting and installing the steel mesh 6. Preferably, this invention utilizes a first electric push rod 55 combined with a telescopic rod 57 to allow for the forward and backward movement of the steel mesh 6. A telescopic rod 57 is also provided between the mounting plate 56 and the first mounting base 54. The mounting plate 56 also has a groove 58 adapted for installing the steel mesh 6, and is fixed by an electromagnet 59. The two electromagnets 59 ensure a secure connection between the steel mesh 6 and the mounting plate 56, while also providing a convenient disassembly and reassembly design, making it more convenient to use.

[0030] like Figure 5 As shown: In this embodiment, the stencil 6 has a second calibration point 61; when the stencil 6 completely covers the PCB below, the first calibration point 25 coincides with the second calibration point 61. The size of the stencil 6 varies when SMT printing PCBs of different specifications and models; the size of the PCB and the stencil 6 in the same batch are custom-made one-to-one. The purpose of this setting is to provide a reference base and parameter settings for movement adjustment through the calibration point. Specifically, after the PCB is installed and positioned, the second calibration point 61 is set on the controllable panel 41 to coincide with the first calibration point 25 to achieve reference positioning. The operator starts the first motor 51, which drives the first lead screw 52 to rotate, thereby moving the first mounting base 54 left and right with the cooperation of the first auxiliary rod 53. Simultaneously, movement is achieved in the front-back direction via the first electric push rod 55, thus ensuring accurate positioning of the stencil 6 and the PCB. This invention solves the problems of cumbersome, time-consuming, and low-accuracy positioning of the stencil and PCB reference in traditional SMT printing. It features one-click operation, which is convenient, fast, efficient, and accurate, greatly improving the quality of SMT printing.

[0031] like Figure 1As shown: In this embodiment, a scraper 8 and a spray pipe 9 are connected to the back plate 4 and above the steel mesh 6 via a second drive 7, with a sufficient distance maintained between the scraper 8 and the spray pipe 9; the second drive 7 is configured to drive the scraper 8 and the spray pipe 9 to move left and right and forward and backward as a whole, and can perform height adjustment operations for the scraper 8 to move away from or closer to the steel mesh 6. Specifically, as... Figure 6 As shown: The second drive 7 includes a second lead screw 71, a second motor 72, a second auxiliary rod 73, a second mounting base 74, a second electric push rod 75, and a carrier plate 76. The second lead screw 71 is rotatably mounted on the back plate 4, parallel to the first lead screw 52, ​​and located above the first lead screw 52. The second motor 72 is fixedly mounted on the side wall of the back plate 4 via a bracket and connected to the second lead screw 71. The second motor 72 is a servo-controlled motor, allowing for more precise forward and reverse rotation control. The second auxiliary rod 73 is mounted on the back plate 4 and parallel to the second lead screw 71. The second mounting base 74 is threaded to the second lead screw 71 and slidably connected to the second auxiliary rod 73. One end of the second electric push rod 75 is mounted on the second mounting base 74, and the other end is connected to the carrier plate 76. A stretchable connecting arm 77 is also provided between the carrier plate 76 and the second mounting base 74. The carrier plate 76 is connected to the scraper 8 via a third electric push rod 78. In a preferred embodiment, a transfer seat may be provided between the scraper 8 and the third electric push rod 78. The transfer seat is connected and fixed to the scraper 8. The purpose of this arrangement is mainly to meet the requirements of different solder thicknesses, so as to adjust the up and down movement of the scraper 8.

[0032] The specific working principle is as follows: In the initial state, the squeegee 8 is located on the left side of the worktable 1. The relative position of the squeegee 8 and the stencil 6 is adjusted by the third electric push rod 78 to ensure that the squeegee 8 is close to the stencil 6 and in a corresponding position to ensure the subsequent comprehensive scraping of solder paste. When the operator starts the second motor 72 to rotate forward, the second motor 72 drives the second lead screw 71 to rotate clockwise. In turn, with the guidance of the second auxiliary rod 73, the second mounting base 74 can be moved to the right. The rightward movement of the second mounting base 74 simultaneously drives the squeegee 8 to move from left to right to complete the full coverage of PCB solder paste in a single operation. Then, it is reset. After the stencil 6 moves backward and misaligns with the PCB, the finished PCB after the SMT printing operation is removed, and a new PCB to be processed is placed, and this cycle is repeated.

[0033] like Figure 6 As shown: In this embodiment, the spray pipes 9 are vertically distributed on the carrier plate 76, and the spray pipes 9 are used to apply solder paste to the PCB. Figure 9As shown: A cavity 43 is provided at the lower part of the back plate 4; and a heating tank 10 is provided inside the cavity 43. A resistance wire 101 and a temperature probe 102 are provided on the side wall of the heating tank 10. The resistance wire 101 and the temperature probe 102 are electrically connected. The temperature probe 102 is used to detect the temperature inside the heating tank 10 in real time, and is connected to the controller 42, and transmits the feedback signal to the resistance wire 101 to achieve intelligent and precise high-efficiency heat treatment of solder paste. A liquid pump 104 is provided on one side of the heating tank 10. Both the liquid pump 104 and the electromagnetic flow control valve 106 can be operated through the controllable panel 41. One end of the liquid pump 104 is connected to the spray pipe 9 through a liquid delivery pipe 105. The liquid delivery pipe 105 is long enough and is also equipped with an electromagnetic flow control valve 106. The size adjustment of the electromagnetic flow control valve 106 directly reflects the control of the flow rate of solder paste. The heating tank 10 is also equipped with a stirring element 103 to maintain the fluidity of the solder paste. Preferably, the stirring element 103 includes a stirring motor 107, a stirring shaft 108, and stirring rods 109. The stirring motor 107 is located at the bottom of the heating tank 10, and the stirring shaft 108 is vertically distributed within the heating tank 10 and connected to the stirring motor 107. Multiple stirring rods 109 are arranged on the stirring shaft 108, and the multiple stirring rods 109 distributed from top to bottom gradually increase in size. This arrangement aims to ensure the fluidity of the solder paste after thawing and heating, facilitating output.

[0034] like Figure 9 and Figure 10As shown: In a preferred embodiment, a storage chamber 44 is provided above the heating tank 10. The storage chamber 44 is connected to the heating tank 10 via an exhaust pipe 45. The exhaust pipe 45 is designed primarily to utilize waste heat, accelerate the defrosting of refrigerated solder paste, achieve rational resource utilization, and reduce energy consumption. The storage chamber 44 is inclined, with an inlet pipe 46 connected to one side and an outlet pipe 47 connected to the heating tank 10 on the other side. Operators can add refrigerated solder paste through the storage chamber 44. Electromagnetic valves are provided on the exhaust pipe 45, inlet pipe 46, and outlet pipe 47. Solder paste is then conveyed into the heating tank 10 through the outlet pipe 47. Specifically, in the initial state, the electromagnetic valve on the exhaust pipe 45 is closed; the operator opens the electromagnetic valves on the inlet pipe 46 and outlet pipe 47, conveying the refrigerated and frozen solder paste into the heating tank 10 through the storage chamber 44. When the amount of solder paste in the heating tank 10 reaches a certain level, the electromagnetic valve on the outlet pipe 47 closes. The operator continues to add solder paste, which is now stored in the storage chamber 44. After a certain amount of solder paste has been added to the storage chamber 44, the operator closes the solenoid valve of the feed pipe 46. Using the control panel 41, parameters are set for the temperature probe 102, and the resistance wire 101 is turned on to heat the solder paste until it is completely thawed. The stirring motor 107 is then turned on, driving the stirring rod 109 to rotate, improving the uniformity of mixing among the raw material components while ensuring the fluidity of the solder paste mixture. Simultaneously, the solenoid valve on the exhaust pipe 45 is opened. The exhaust pipe 45 is also equipped with a one-way valve to ensure that only airflow enters the storage chamber 44.

[0035] With the exhaust pipe 45 in the open state, the residual heat airflow in the heating tank 10 enters the storage chamber 44 through the exhaust pipe 45. This residual heat airflow preheats the solder paste in the storage chamber 44. This operation not only greatly improves the sustainability of solder paste use but also avoids the problem of temperature imbalance caused by directly adding frozen solder paste to the solder paste mixture, resulting in poor solder paste use and quality. Solder paste in non-use state is generally stored in an environment with certain refrigeration conditions. That is, the solder paste needs to be thawed to room temperature before it can be effectively used. This invention optimizes the structural design and makes rational use of resources, solving the problems of poor use effect of traditional solder paste thawing methods, inability to achieve integrated structure, high efficiency, and energy-saving use of solder paste by utilizing residual heat, resulting in low operating efficiency and high energy consumption. When the liquid pump 104 is turned on, it will drive the flowing solder paste from the liquid inlet tube 105 to the liquid spray tube 9 and then add it to the PCB board. The squeegee 8 moves from left to right, and the liquid spray tube 9 is to the right of the squeegee 8. Therefore, after the solder paste is delivered, the second motor 72 starts, which in turn drives the squeegee 8 to perform SMT printing on the solder paste on the stencil 6.

[0036] Example 2: Based on Example 1, as follows Figure 11As shown: A high-efficiency and energy-saving SMT printing fixture further includes: a leveling component 11 at the bottom of the worktable 1, the leveling component 11 including an indicator light 111, a level detection sensor 112, and a support foot 113. The indicator light 111 is located on the front of the worktable 1 and includes red and green indicators; the level detection sensor 112 is located on the bottom surface of the worktable 1 and is electrically connected to the indicator light 111; wherein, red indicates that the level support condition has not been met, and green indicates that the worktable 1 is currently level. The support foot 113 mainly consists of a rubber protrusion 114 and a vertically distributed connecting rod 115 located at the center of the rubber protrusion 114, the connecting rod 115 being threadedly connected to the bottom surface of the worktable 1. The purpose of this design is to adjust the stability and levelness of the four corner supports of the workbench 1 by rotating the support feet 113, thereby improving the versatility of the SMT printing fixture and avoiding the uneven ground support in traditional work scenarios. The goal is to provide a stable horizontal support plane and prevent PCB deformation during SMT printing operations.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-efficiency and energy-saving SMT printing fixture, characterized in that: The system includes a workbench with horizontally distributed left and right sides, and coordinate points distributed radially (X) and axially (Y) on its surface. A support mechanism is located at the top of the workbench, used for supporting and positioning PCBs of different sizes and specifications, and providing board surface error recognition and alarm functions. A cleaning device for periodically cleaning the stencil is located below the workbench. A backplate is located at the rear of the workbench, with a control panel on the right side. This control panel is connected to a controller, which has functions for program programming, module embedding, signal transmission, and command control. Above the backplate and above the workbench, a stencil is connected via a first drive mechanism, allowing the stencil to move left and right and forward and backward. The stencil has a second calibration point; a scraper and a spray pipe are connected to the back plate above the stencil via a second drive, with sufficient distance maintained between them; the second drive is configured to move the scraper and spray pipe as a whole, adjusting their left and right and forward and backward movements, and adjusting the scraper's height relative to the stencil; a cavity is provided at the bottom of the back plate; a heating tank is provided within the cavity, with a resistance wire and a temperature probe on the side wall of the heating tank, the resistance wire and temperature probe being electrically connected; a stirring element is also provided inside the heating tank to maintain the fluidity of the solder paste; a liquid pump is provided on one side of the heating tank, one end of which is connected to the spray pipe via a sufficiently long delivery pipe, which is also equipped with an electromagnetic flow control valve.

2. The high-efficiency and energy-saving SMT printing fixture as described in claim 1, characterized in that: A leveling component is also provided at the bottom of the workbench. The leveling component includes an indicator light, a level detection sensor, and a support foot. The indicator light is located on the front of the workbench and includes red and green colors. The level detection sensor is located on the bottom surface of the workbench and is electrically connected to the indicator light. The support foot mainly consists of a rubber protrusion and a connecting rod located at the center of the rubber protrusion and vertically distributed. The connecting rod is connected to the bottom surface of the workbench by a thread.

3. The high-efficiency and energy-saving SMT printing fixture as described in claim 2, characterized in that: The support mechanism includes a base plate, guide rods, and cylinders. The base plates are horizontally distributed, with four plates positioned at the four corners. The upper surface of each base plate is provided with insertion posts for connecting to PCB board holes. When the four base plates are closed, the four insertion posts are arranged in a square. The left front base plate is fixedly mounted on the worktable. The left front base plate is connected to the right front base plate and the left rear base plate via cylinders. The right rear base plate is slidably connected to the left rear base plate and the right front base plate via guide rods. The left front base plate also has a first calibration point located at coordinates (X0, Y0), corresponding to the position of the insertion posts on the base plate. The surface of the left front base plate also has a camera and a voice alarm connected to the camera.

4. The high-efficiency and energy-saving SMT printing fixture as described in claim 3, characterized in that: A guide is provided between the right front substrate and the worktable. The guide includes a guide bar and a guide groove. The guide bar is disposed on the right front substrate, and the guide groove is opened on the worktable. The guide bar and the guide groove are matched and installed. The structure between the left rear substrate and the worktable is the same as the structure between the right front substrate and the worktable.

5. The high-efficiency and energy-saving SMT printing fixture as described in claim 4, characterized in that: The cleaning component includes a cleaning chamber, a rotating shaft, a rotating frame, and an ultrasonic generator. The cleaning chamber is located at the bottom of the workbench and has a door on one side. The rotating shaft is vertically arranged in the cleaning chamber and has a rotating motor connected to its bottom end. The rotating frame is located on the rotating shaft and has a rectangular frame structure. One side of the rotating frame has an installation groove for mounting a steel mesh. The ultrasonic generator is located inside the cleaning chamber.

6. The high-efficiency and energy-saving SMT printing fixture as described in claim 5, characterized in that: The first drive includes a first motor, a first lead screw, a first auxiliary rod, a first mounting base, a first electric push rod, and a mounting plate; the first motor is mounted on the back plate via a bracket, the first lead screw is rotatably mounted between the left and right side walls of the back plate and connected to the first motor; the first auxiliary rod is mounted on the back plate and is parallel to the first lead screw; the first mounting base is mounted on the first lead screw and the first auxiliary rod, and is threadedly connected to the first lead screw and slidably connected to the first auxiliary rod; the first electric push rod is distributed front and rear on the first mounting base, and its other end is connected to the mounting plate.

7. The high-efficiency and energy-saving SMT printing fixture as described in claim 6, characterized in that: A telescopic rod is also provided between the mounting plate and the first mounting base; the mounting plate is also provided with a groove adapted for the installation of steel mesh, and is fixed by electromagnet.

8. The high-efficiency and energy-saving SMT printing fixture as described in claim 7, characterized in that: The second drive includes a second lead screw, a second motor, a second auxiliary rod, a second mounting base, a second electric push rod, and a carrier plate. The second lead screw is rotatably mounted on the back plate and parallel to the first lead screw. The second motor is fixedly mounted on the side wall of the back plate via a bracket and connected to the second lead screw. The second auxiliary rod is mounted on the back plate and parallel to the second lead screw. The second mounting base is threaded to the second lead screw and slidably connected to the second auxiliary rod. One end of the second electric push rod is mounted on the second mounting base, and the other end is connected to the carrier plate. A stretchable connecting arm is also provided between the carrier plate and the second mounting base. The carrier plate is connected to the scraper via a third electric push rod. The spray pipes are vertically distributed on the carrier plate.

9. The high-efficiency and energy-saving SMT printing fixture as described in claim 8, characterized in that: The stirring components include a stirring motor, a stirring shaft, and stirring rods; the stirring motor is located at the bottom of the heating tank, the stirring shaft is vertically distributed in the heating tank and connected to the stirring motor; the stirring rods are multiple rods arranged on the stirring shaft, and the multiple stirring rods distributed from top to bottom gradually increase in size.

10. The high-efficiency and energy-saving SMT printing fixture as described in claim 9, characterized in that: A storage chamber is provided above the heating barrel, and the storage chamber is connected to the heating barrel through an exhaust pipe. The storage chamber is inclined and connected to the heating barrel through an inlet pipe on one side and an outlet pipe on the other side. Electromagnetic switch valves are provided on the exhaust pipe, the inlet pipe, and the outlet pipe.

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