A precision printed circuit board processing technology

Abstract

The present invention relates to the technical field of circuit board processing, and discloses a precision printed circuit board processing technology, including S1, designing the circuit board according to actual needs, including wiring and component installation positions; S2, printing conductive silver paste on a substrate by a silk screen printing device to form a conductive layer of the circuit board, and cutting the bulk copper clad laminate into a desired size and shape by a cutting process; S3, covering the copper clad laminate with a photosensitive resist coating, and transferring the designed circuit pattern to the copper clad laminate by exposure and development. The precision printed circuit board processing technology can effectively solve the problem that the prior art generally uses double-sided circuit boards in order to meet the needs of miniaturization, high performance and complexity of electronic equipment. Circuits are laid on both surfaces of the double-sided circuit board. The conductive layer of the circuit connection area of ​​the printed circuit board needs to be carried out step by step, and the double-sided printing of the circuit board cannot be completed synchronously in the same processing flow, resulting in low manufacturing efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of circuit board processing, and in particular to a precision printed circuit board processing technology. Background Art

[0002] Circuit board, also known as circuit board or PCB board, is a conductive board used to connect and support electronic components. It completes the electrical connection of electronic products by printing or etching metal conductive paths on insulating substrates and soldering electronic components. Circuit boards are an indispensable component of modern electronic devices and are widely used in various fields such as computers, mobile phones, home appliances, industrial control systems, etc.

[0003] In the prior art, in order to meet the needs of miniaturization, high performance and complexity of electronic equipment, double-sided circuit boards are generally used. Circuits are laid on both surfaces of the double-sided circuit boards. When printing the conductive layer of the circuit connection area of ​​the circuit board, it is necessary to proceed step by step. It is impossible to complete double-sided printing of the circuit board in the same processing flow, and the manufacturing efficiency is low. Summary of the invention

[0004] Technical issues solved

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides a precision printed circuit board processing technology, which can effectively solve the problem in the prior art that, in order to meet the needs of miniaturization, high performance and complexity of electronic equipment, double-sided circuit boards are generally used, both surfaces of the double-sided circuit boards are laid with circuits, and the conductive layer of the circuit connection area of ​​the printed circuit board needs to be carried out step by step, and the double-sided printing of the circuit board cannot be completed synchronously in the same processing flow, resulting in low manufacturing efficiency.

[0006] Technical Solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] The present invention provides a precision printed circuit board processing technology, which is characterized by comprising:

[0009] S1. Design the circuit board according to actual needs, including wiring and component installation positions;

[0010] S2, printing the conductive silver paste on the substrate through the screen printing equipment to form the conductive layer of the circuit board, and cutting the large copper clad laminate into the required size and shape through the cutting process;

[0011] S3, using a photosensitive resist coating to cover the copper clad laminate, and transferring the designed circuit pattern to the copper clad laminate through an exposure and development process;

[0012] S4, use chemical solution to etch away the copper foil not protected by the resist, leaving the designed circuit pattern, and plate a layer of metal on the copper foil to prevent oxidation and provide a good soldering surface;

[0013] S5. Drill holes on both sides of the circuit board to achieve electrical connection between layers;

[0014] S6. A thin layer of copper is plated in the hole by electroplating to increase the conductivity of the via hole;

[0015] S7. Perform some surface treatment on the circuit board, and then perform functional testing and debugging to ensure the reliability of the circuit board;

[0016] The screen printing device in S2 includes a flip portion, the flip portion includes a rotating shaft, the rotating shaft is connected to an output shaft through a rotating groove provided on its circumferential surface for damping rotation, and four output shafts are arranged and distributed in a circumferential array with the rotating shaft as the center;

[0017] The printing part includes a clamping mechanism, the clamping mechanism includes a fixed frame, the side of the fixed frame is fixedly connected to the output end of the output shaft, the inner side of the fixed frame away from the output shaft is fixedly connected with a magnetic block, the outer side of the magnetic block is provided with a slide rail rod that fits and slides with the inner wall groove of the fixed frame, the slide rail rod is provided with two and symmetrically distributed with the magnetic block as the center, the middle part of the slide rail rod is fixedly connected with a fixed block, and the fixed block is connected with a right-angle block that slides with the outer surface of the slide rail rod through a spring group arranged on the outer side thereof;

[0018] Among them, a bevel gear is sleeved on the circumferential outer surface of the output shaft near one end of the rotating shaft, a hollow column is arranged on the circumferential outer surface of the rotating shaft, a driving motor inside the hollow column is transmission-connected to the bottom of the rotating shaft, a groove is opened at one end of the hollow column, and an arc surface design is adopted at the connection between the inner wall of the groove and the hollow column, a bevel tooth column meshing with the tooth surface of the bevel gear is arranged on the outside of the rotating shaft near the groove, a special-shaped groove fitting with the top end of the hollow column is opened on the circumferential outer surface of the output shaft, and the side of the special-shaped groove is designed with an arc surface.

[0019] Furthermore, a triangle plate is fixedly connected to one side of the right-angle block, an electromagnet is provided at the port of the right-angle block, and the printing unit also includes a silk-screen printing mechanism, below which is provided a lifting mechanism for cooperating with the silk-screen printing mechanism to print circuit boards, and the lifting mechanism is symmetrically provided with a lifting platform around the rotating axis.

[0020] Furthermore, the silk-screen printing mechanism includes a screen plate, which is slidably connected to a top frame via a sliding rod fixedly connected to its upper surface, a side of the lower surface of the top frame away from the sliding rod is fixedly connected to a power distribution cabinet, a side of the screen plate is fixedly connected to a connecting rod, and an end of the connecting rod away from the screen plate is fixedly connected to a pressure plate.

[0021] Furthermore, the lifting mechanism includes a base, a limiting frame is fixedly connected to the upper surface of the base, the limiting frame is slidably connected to a lifting rod at a side away from the base through a square hole opened inside the limiting frame, one end of the lifting rod close to the pressure plate is fixedly connected to a supporting plate, the other end of the lifting rod is rotatably connected to a rotating rod, the end of the rotating rod away from the lifting rod is rotatably connected to a lifting column through a rotating shaft, and the rotating rod is connected to a support frame fixedly connected to the upper surface of the base through a displacement groove opened in the middle thereof.

[0022] Furthermore, one end of the lifting column away from the base is fixedly connected to a bottom plate, an arc plate group is provided on the upper surface of the bottom plate, the other end of the arc plate group is connected to a nail plate, nail pins are fixedly connected to the upper surface of the nail plate, a plurality of nail pins are distributed in the nail pin array, and a positioning piece is provided on the side of the nail plate, and four positioning pieces are provided.

[0023] Furthermore, the positioning member includes a rotating seat, one side of which is fixedly connected to the side of the nail plate, the interior of the rotating seat is rotatably connected to an L-shaped plate via an axial rod, and the circumferential outer surface of the axial rod is sleeved with a torsion spring connected to the interior of the L-shaped plate, and a micro-nail is arranged on the side of the L-shaped plate away from the nail plate, and a plurality of micro-nail arrays are distributed.

[0024] Furthermore, a silicone strip is provided on the L-shaped plate perpendicular to the inner wall of the micro-nail, and a slot is provided on the upper end of the silicone strip.

[0025] Beneficial Effects

[0026] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0027] The present invention is provided with a rotating shaft, an output shaft and a clamping mechanism. By placing the circuit board inside the clamping mechanism, after the first side of the circuit board is printed, the rotating shaft drives the output shaft to transfer, so that the bevel gear on the outer circumferential surface of the output shaft meshes with the bevel gear column to perform a damping rotation of 180 degrees, completing the turning over of the clamping mechanism and the circuit board, without manual turning over, thereby improving production efficiency. A total of four output shafts are provided, corresponding to four processing stations, and the loading, unloading, first side printing and second side printing of multiple circuit boards are realized simultaneously, thereby improving the production efficiency of circuit board printing. The nail pins and micro nails in contact with the lower surface of the circuit board have sharp tips, which will not damage the printed silver paste coating. At the same time, they are distributed more densely, and the size of the nail plate is the same as that of the circuit board. During the process of pressing the screen down, due to the large contact area and low pressure, damage to the circuit board is avoided. When the nail board is lifted up, the upper surface of the circuit board contacts the lower surface of the upper triangle plate, and the lower surface of the circuit board contacts the top of the micro nails and nail needles on the four positioning parts. The four sides and the upper and lower ends of the circuit board are positioned, completing the calibration of the position of the circuit board, ensuring the accurate position of the circuit board during the printing process, thereby improving the printing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A flow chart of a circuit board manufacturing process according to an embodiment of the present invention;

[0030] Figure 2 It is a three-dimensional structural schematic diagram of an embodiment of the present invention;

[0031] Figure 3 This is a schematic structural diagram of a turning portion according to an embodiment of the present invention;

[0032] Figure 4 It is a schematic diagram of the three-dimensional structure of the clamping mechanism and the output shaft according to an embodiment of the present invention;

[0033] Figure 5 It is a schematic structural diagram of a clamping mechanism, a screen printing mechanism and a lifting mechanism according to an embodiment of the present invention;

[0034] Figure 6 It is a structural schematic diagram of a lifting mechanism, a connecting rod and a pressing plate according to an embodiment of the present invention;

[0035] Figure 7 It is a structural schematic diagram of a lifting mechanism and a right-angle block according to an embodiment of the present invention;

[0036] Figure 8 For the embodiment of the present invention Figure 7 A schematic diagram of the structure with a partial enlargement at the center;

[0037] Fig. 9 Schematic diagram of the separation structure of the positioning member according to an embodiment of the present invention.

[0038] The numbers in the figure represent:

[0039] 1. Turning part; 11. Rotating shaft; 12. Output shaft; 13. Bevel gear; 14. Hollow column; 15. Bevel gear column; 16. Special-shaped groove; 2. Printing part; 21. Clamping mechanism; 211. Fixed frame; 212. Magnetic block; 213. Slide rail rod; 214. Fixed block; 215. Spring group; 216. Right-angle block; 217. Triangle plate; 22. Silk-screen printing mechanism; 221. Screen plate; 222. Top frame; 223. Connection Rod; 224, pressure plate; 23, lifting mechanism; 231, base; 232, limit frame; 233, lifting rod; 234, supporting plate; 235, rotating rod; 236, lifting column; 237, arc plate group; 238, nail plate; 239, nail pin; 24, lifting platform; 25, positioning piece; 251, rotating seat; 252, L-shaped plate; 253, torsion spring; 254, micro nail; 255, silicone strip; 256, slot. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] The present invention will be further described below in conjunction with the embodiments.

[0042] Example:

[0043] See also Figure 1-Figure 9 The present invention provides a precision printed circuit board processing technology, which is characterized by comprising:

[0044] S1. Design the circuit board according to actual needs, including wiring and component installation positions;

[0045] S2, printing the conductive silver paste on the substrate through the screen printing equipment to form the conductive layer of the circuit board, and cutting the large copper clad laminate into the required size and shape through the cutting process;

[0046] S3, using a photosensitive resist coating to cover the copper clad laminate, and transferring the designed circuit pattern to the copper clad laminate through an exposure and development process;

[0047] S4, use chemical solution to etch away the copper foil not protected by the resist, leaving the designed circuit pattern, and plate a layer of metal on the copper foil to prevent oxidation and provide a good soldering surface;

[0048] S5. Drill holes on both sides of the circuit board to achieve electrical connection between layers;

[0049] S6. A thin layer of copper is plated in the hole by electroplating to increase the conductivity of the via hole;

[0050] S7. Perform some surface treatment on the circuit board, and then perform functional testing and debugging to ensure the reliability of the circuit board;

[0051] The screen printing device in S2 includes a flip part 1, the flip part 1 includes a rotating shaft 11, the rotating shaft 11 is connected to an output shaft 12 through a rotating groove provided on its circumferential surface for damping rotation, and four output shafts 12 are arranged and distributed in a circumferential array with the rotating shaft 11 as the center;

[0052] The printing part 2 includes a clamping mechanism 21, and the clamping mechanism 21 includes a fixed frame 211. The side of the fixed frame 211 is fixedly connected to the output end of the output shaft 12. The inner side of the fixed frame 211 away from the output shaft 12 is fixedly connected with a magnetic block 212. The outer side of the magnetic block 212 is provided with a slide rail rod 213 that fits and slides with the inner wall groove of the fixed frame 211. The slide rail rod 213 is provided with two and is symmetrically distributed with the magnetic block 212 as the center. The middle part of the slide rail rod 213 is fixedly connected with a fixed block 214. The fixed block 214 is connected to a right-angle block 216 that slides with the outer surface of the slide rail rod 213 through a spring group 215 provided on the outer side thereof;

[0053] Among them, a bevel gear 13 is sleeved on the circumferential outer surface of the output shaft 12 near one end of the rotating shaft 11, a hollow column 14 is provided on the circumferential outer surface of the rotating shaft 11, a driving motor inside the hollow column 14 is transmission-connected to the bottom of the rotating shaft 11, a groove is provided at one end of the hollow column 14, and an arc surface design is adopted at the connection between the inner wall of the groove and the hollow column 14, a bevel gear column 15 meshing with the tooth surface of the bevel gear 13 is provided on the outside of the rotating shaft 11 near the groove, a special-shaped groove 16 fitting with the top of the hollow column 14 is provided on the circumferential outer surface of the output shaft 12, and the side of the special-shaped groove 16 is designed with an arc surface, which can ensure that the output shaft 12 can be turned over steadily.

[0054] A triangle plate 217 is fixedly connected to one side of the right-angle block 216, and an electromagnet is provided at the port of the right-angle block 216. The printing unit 2 also includes a silk-screen printing mechanism 22, and a lifting mechanism 23 is provided below the silk-screen printing mechanism 22 for printing circuit boards. The lifting mechanism 23 is symmetrically provided with a lifting platform 24 around the rotating shaft 11. The two lifting platforms 24 and the two silk-screen printing mechanisms 22, a total of four workstations, can synchronously complete the loading, unloading, first-side printing and second-side printing of multiple circuit boards, thereby improving the production efficiency of circuit board printing.

[0055] The screen printing mechanism 22 includes a screen plate 221, which is slidably connected to a top frame 222 via a sliding rod fixedly connected to its upper surface. A side of the bottom surface of the top frame 222 away from the sliding rod is fixedly connected to a power distribution cabinet. A connecting rod 223 is fixedly connected to the side of the screen plate 221, and a pressure plate 224 is fixedly connected to the end of the connecting rod 223 away from the screen plate 221.

[0056] The lifting mechanism 23 includes a base 231, and a limiting frame 232 is fixedly connected to the upper surface of the base 231. The limiting frame 232 is slidably connected to a lifting rod 233 through a square hole opened inside the limiting frame 232 away from the base 231, ensuring that the lifting rod 233 always remains vertical. The end of the lifting rod 233 close to the pressure plate 224 is fixedly connected to a supporting plate 234, and the other end of the lifting rod 233 is rotatably connected to a rotating rod 235. The end of the rotating rod 235 away from the lifting rod 233 is rotatably connected to a lifting column 236 through a rotating shaft. The rotating rod 235 is connected to a support frame fixedly connected to the upper surface of the base 231 through a shifting groove opened in the middle thereof. The shifting groove enables the lifting column 236 to always be perpendicular to the base 231 after the rotating rod 235 changes its center of gravity.

[0057] One end of the lifting column 236 away from the base 231 is fixedly connected to the bottom plate, and an arc plate group 237 is arranged on the upper surface of the bottom plate. The other end of the arc plate group 237 is connected to the nail plate 238, and the upper surface of the nail plate 238 is fixedly connected to nail pins 239, and there are multiple nail pins 239 distributed in an array. A positioning piece 25 is arranged on the side of the nail plate 238, and there are four positioning pieces 25.

[0058] The positioning member 25 includes a rotating seat 251, one side of which is fixedly connected to the side of the nail plate 238, the interior of the rotating seat 251 is rotatably connected to an L-shaped plate 252 via an axial rod, and the circumferential outer surface of the axial rod is sleeved with a torsion spring 253 connected to the interior of the L-shaped plate 252, and a micro-nail 254 is arranged on the side of the L-shaped plate 252 away from the nail plate 238, and a plurality of micro-nail 254 are distributed in an array.

[0059] A silicone strip 255 is disposed perpendicular to the inner wall of the L-shaped plate 252 and the micro nails 254 . A slot 256 is formed at the upper end of the silicone strip 255 . The silicone strip 255 increases friction and can better fix the circuit board.

[0060] refer to Figure 1-Figure 9 In the prior art, in order to meet the needs of miniaturization, high performance and complexity of electronic equipment, double-sided circuit boards are generally used. Circuits are laid on both surfaces of the double-sided circuit boards. When printing the conductive layer of the circuit connection area of ​​the circuit board, it is necessary to proceed step by step. It is impossible to complete the double-sided printing of the circuit board in the same processing flow, and the manufacturing efficiency is low.

[0061] In order to overcome the above-mentioned defects, the present invention designs a precision printed circuit board processing technology, wherein the screen printing equipment in S2 can realize the automatic flipping function of the circuit board when printing the circuit board, and can complete the printing of both sides of the circuit board in the same process.

[0062] Circuit board material process:

[0063] In actual applications, a lifting platform 24 of the printing section 2 places the circuit board to be processed through an external manipulator, and the rotating shaft 11 of the flip section 1 drives the clamping mechanism 21 to move to the top of the lifting platform 24. At this time, the current inside the right-angle block 216 is disconnected, the electromagnets at both ends of the adjacent right-angle blocks 216 lose their magnetic force, and the spring group 215 in a compressed state on the outside of the fixed block 214 loses the extrusion force and quickly bounces to both sides. The lifting platform 24 starts to run, driving the circuit board to rise, until the circuit board is in the middle of the upper and lower triangles 217 and then stops running. At this time, the current inside the right-angle block 216 starts to flow, and the electromagnets at both ends of the adjacent right-angle blocks 216 are quickly attracted. The magnetic force of the electromagnet is greater than the pressure of the spring group 215. The pair of right-angle blocks 216 on the outer surface of the slide rail rod 213 are quickly approached to the fixed block 214 by the port electromagnet, and the pair of right-angle blocks 216 ports on both sides of the magnetic suction block 212 are also affected by magnetism, and their adjacent two ends are respectively attracted to the positive and negative poles on both sides of the magnetic suction block 212, driving the slide rail rods 213 on both sides to synchronously approach the magnetic suction block 212 in the slide groove of the fixed frame 211. At this time, the four directions of the circuit board are clamped and positioned by the right-angle block 216, and the fixed block 214 and the magnetic suction block 212 are both set in the middle of the adjacent right-angle block 216, so the right-angle block 216 can be squeezed toward the circuit board axially symmetrically under the influence of magnetic force. The lifting platform 24 returns to its initial height, and at the same time, the driving motor under the rotating shaft 11 starts to run, and the rotating shaft 11 starts to rotate, driving the output shaft 12 to rotate counterclockwise. At this time, the lower surface of the special-shaped groove 16 opened at the output shaft 12 fits with the upper surface of the hollow column 14, and the rotating shaft 11 drives the clamping mechanism 21 to move 90 degrees counterclockwise to just above the lifting mechanism 23.

[0064] Single-sided printing process of circuit board:

[0065] After the rotating shaft 11 stops rotating, the lower surface of its special-shaped groove 16 is still in contact with the upper surface of the hollow column 14. The power distribution cabinet gives an instruction to lower the mesh plate 221 to a specified stroke. The mesh plate 221 drives the connecting rod 223 and the pressure plate 224 to descend synchronously. The lower surface of the pressure plate 224 is in contact with the upper surface of the supporting plate 234. As the descending depth increases, the supporting plate 234 is driven to move downward synchronously, and the lifting rod 233 slides and descends in the square hole inside the limit frame 232. The lifting rod 233 rotates away from the side of the supporting plate 234. The lifting column 236 is rotatably connected with a rotating rod 235, and a shifting groove is opened in the middle of the rotating rod 235. The shifting groove ensures that the lifting column 236 and the lifting rod 233 always move up and down perpendicular to the base 231. A support frame is rotated through an axis in the shifting groove. The end of the rotating rod 235 away from the lifting rod 233 is rotatably connected to the outer surface of the lifting column 236. Under the action of the lever principle, as the lifting rod 233 descends, the lifting column 236 rises under the prying of the front and rear four rotating rods 235. The lifting column 236 adopts a hollow design to reduce its weight impact and is easy to lift.

[0066] The base plate rises with the lifting column 236, and the upper surface of the base plate is connected to the nail plate 238 through the arc plate group 237. The four sides of the nail plate 238 are provided with positioning parts 25. The side of the rotating seat 251 of the positioning part 25 is fixedly connected to the side of the nail plate 238. In the initial state, the L-shaped plate 252 is inclined inside the rotating seat 251 due to the influence of the internal torsion spring 253. As the mesh plate 221 continues to descend, the micro nails 254 above the four L-shaped plates 252 are the first to contact the lower surface of the circuit board.

[0067] As the nail plate 238 continues to rise, the four L-shaped plates 252 support the circuit board and squeeze it upward until the four corners of its upper surface contact the lower surface of the upper triangular plate 217. Under the double-sided action of the upper triangular plate 217 and the lower nail plate 238, the lower surface of the circuit board fits with the top of the micro nails 254 and the nail pins 239. At this time, the top height of the micro nail 254 is the same as the top height of the nail pin 239. The four L-shaped plates 252 are all in a horizontal state, and the distance between the short sides of the two opposite L-shaped plates 252 in the horizontal state is equal to that of the circuit board. The slot 256 at the silicone strip 255 on the side of the L-shaped plate 252 tightly fits the side wall of the circuit board, clamps the circuit board to the upper surface of the nail plate 238, and performs position correction to reduce the low printing accuracy caused by the skewed placement angle. At this time, the lower surface of the screen 221 is in contact with the upper surface of the right-angle block 216. At this time, the screen 221 has reached the specified stroke and stops pressing down. At the same time, the internal current of the right-angle block 216 in the clamping mechanism 21 is disconnected, and the electromagnets at both ends of the adjacent right-angle blocks 216 lose their magnetic force and expand outward under the elastic force of the spring group 215. The arc plate group 237 plays a buffering role in the process of the screen 221 pressing down. At the same time, the arc plate group 237 has a shorter variable stroke and has a certain supporting force. After the right-angle block 216 slides away, the circuit board continues to rise a small distance due to the residual force of the arc plate group 237, so that the circuit board and the upper surface of the right-angle block 216 are at the same horizontal height, and the whole is in contact with the lower surface of the screen 221. At the same time, the lower surface of the support plate 234 is in contact with the upper surface of the limit frame 232, which improves the stability of the printing process and ensures the accuracy of the silver paste circuit printing.

[0068] After stabilization, the scraper on the upper surface of the screen 221 starts to move, and scrapes back and forth according to the actual number of times required. After printing is completed, the distribution cabinet controls the sliding rod to slide a short distance to the upper part of the machine top frame 222, and the supporting plate 234 follows the pressure plate 224 at the screen 221 upward for a short distance. This distance is smaller than the distance between the upper and lower triangular plates 217. After the lifting column 236 is lowered accordingly, the circuit board is located between the upper and lower triangular plates 217. At the same time, the current starts to flow inside the right-angle block 216 in the clamping mechanism 21, and the electromagnets at both ends of the adjacent right-angle blocks 216 are acted upon by magnetic force, and the right-angle blocks 216 at the four corners are squeezed close to the circuit board.

[0069] Then the mesh plate 221 slides upward with the slide rod to return to the highest point of the initial state, and the lifting column 236, nail plate 238 and positioning member 25 below lose the squeezing of the pressure plate 224 and move downward. In the downward process, the four positioning members 25 clamp the circuit board downward, and when the lower surfaces of the four corners of the circuit board contact the upper surface of the triangle plate 217 below, the triangle plate 217 gives support force to the circuit board, so that the circuit board is fixed on the upper surface of the triangle plate 217 below, and the lifting column 236 continues to move downward so that the four positioning members 25 are separated from the positioning clamping of the circuit board, and the lower surface of the circuit board is no longer in contact with the nail pins 239 and the top of the micro nails 254, and the L-shaped plate 252 returns to its initial tilted state. At the same time, the lifting column 236 continues to move downward, and the lifting mechanism 23 as a whole returns to its initial state.

[0070] The process of turning over the circuit board to print the second side:

[0071] After the silver paste printing on one side is completed, the driving unit at the bottom drives the rotating shaft 11 to rotate counterclockwise. After the output shaft 12 moves a small distance, the hollow column 14 below the special-shaped groove 16 is provided with a groove, and the plane of the hollow column 14 and the groove are connected with an arc surface design. The output shaft 12 continues to move, and the bevel gear 13 sleeved on the outer surface of its circumference and the bevel tooth column 15 below are meshed with each other. As the output shaft 12 continues to move, the bevel gear 13 drives the output shaft 12 to rotate damped inside the rotating shaft 11 as a whole, and the bevel tooth column 15 supports the output shaft 12 to rotate 180 degrees as a whole, completing the flipping of the clamping mechanism 21 as a whole. At this time, the circuit board is flipped under the clamping of the right-angle block 216 and the triangle plate 217. When the bevel gear 13 is out of engagement with the bevel tooth column 15, since the output shaft 12 is a damped rotation, the output shaft 12 will not continue to rotate due to inertia. At this time, the special-shaped groove 16 has also completed the flipping, and the surface of the hollow column 14 below the output shaft 12 is still a groove. When the output shaft 12 continues to move, the edge of the special-shaped groove 16 adopts an arc surface design. At this time, the arc surface edge of the special-shaped groove 16 is in contact with the arc surface of the upper part of the groove, and it moves steadily until the straight edge of the special-shaped groove 16 below is in contact with the upper surface of the hollow column 14.

[0072] At this time, the rotating shaft 11 stops running after completing the 90-degree rotation, and sends the clamping mechanism 21 to the top of the next lifting mechanism 23 to print the second side of the circuit board. This lifting mechanism 23 and the screen printing mechanism 22 use the same structural design as the first side printing, and the second side of the circuit board is printed synchronously with the previous step (because the nail pins 239 on the nail plate 238 and the tops of the micro nails 254 are very sharp, so the contact with the circuit board after the previous side is printed will not cause the printed silver paste layer to be damaged). After the second side of the circuit board is also printed, the rotating shaft 11 drives the clamping mechanism 21 to move 90 degrees counterclockwise. During this process, the special-shaped groove 16 below the output shaft 12 fits with the upper surface of the hollow column 14, and stops running after reaching the next lifting platform 24.

[0073] Circuit board cutting process:

[0074] The structure of the lifting platform 24 of the unloading part of the circuit board is designed in the same structure as the loading part, and the upper surface of the lifting platform 24 for unloading is also provided with the same structure as the nail pins 239 on the nail plate 238, which is not easy to damage the coating of the printed circuit board. After the circuit board is lowered, it is picked up by an external manipulator and sent to the light curing process for drying. Then the rotating shaft 11 continues to rotate counterclockwise 90 degrees, and the lower surface of the special-shaped groove 16 is in contact with the upper surface of the hollow column 14 and moves smoothly to the upper part of the lifting platform 24 of the loading part at the initial position, thus completing a complete set of printing processes.

[0075] The above printing process has the following advantages:

[0076] Advantage 1: A bevel gear 13 is sleeved on the outer surface of the output shaft 12. When the output shaft 12 moves to above the bevel gear column 15 between the two screen printing mechanisms 22, the output shaft 12 and the clamping mechanism 21 are flipped 180 degrees through the mutual engagement of the teeth, and the circuit board inside the clamping mechanism 21 is flipped synchronously.

[0077] Advantage 2: Two lifting platforms 24 and two screen printing mechanisms 22 are provided, with a total of four workstations, which can simultaneously complete the loading, unloading, first-side printing and second-side printing of multiple circuit boards, thereby improving the production efficiency of circuit board printing.

[0078] Advantage three: the clamping mechanism 21 and the circuit board are turned over after printing on the first side. During processing, when the pressure plate 224 squeezes the supporting plate 234 to the upper surface of the limit frame 232, the screen 221 fits the circuit board as a whole, so that the clamping mechanism 21 remains horizontal during the printing process, which improves the stability of the circuit board during printing and improves the processing accuracy.

[0079] Advantage 4: When the second side of the circuit board is printed and cut, the nail pins 239 and micro nails 254 in contact with the lower surface of the circuit board have pointed tips and will not damage the printed silver paste coating. At the same time, they are densely distributed, and the size of the nail plate 238 is the same as that of the circuit board. During the pressing process of the stencil 221, the contact area is large and the pressure is small, so the circuit board will not be damaged.

[0080] Advantage 5. During the circuit board printing process, the lifting mechanism 23 moves as a whole following the lifting height of the screen 221. When the screen 221 descends, the nail plate 238 rises synchronously to lift the circuit board to cooperate with its printing; after printing is completed, when the screen 221 rises, the nail plate 238 descends synchronously to separate from the circuit board, thereby improving the degree of automation of silk screen printing.

[0081] Advantage 6: When the upper surface of the circuit board is completely in contact with the lower surface of the stencil 221, the four positioning members 25 are on the four sides of the circuit and are all in an extruded state, so that the circuit board is fixed during the printing process, reducing the deviation during the printing process and ensuring that the silver paste is accurately printed at the predetermined position.

[0082] Advantage 7: During the rising process of the nail plate 238, the upper surface of the circuit board contacts the lower surfaces of the four triangles 217 above, and the lower surface of the circuit board contacts the tops of the micro nails 254 and nail needles 239 on the four positioning members 25. As it continues to rise, the four sides and the upper and lower ends of the circuit board are positioned, completing the verification of the position of the circuit board, ensuring the accurate position of the circuit board during the printing process, thereby improving the printing accuracy.

[0083] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A precision printed circuit board processing technology, characterized in that: include: S1. Design the circuit board according to actual needs, including wiring and component installation positions; S2, printing the conductive silver paste on the substrate through the screen printing equipment to form the conductive layer of the circuit board, and cutting the large copper clad laminate into the required size and shape through the cutting process; S3, using a photosensitive resist coating to cover the copper clad laminate, and transferring the designed circuit pattern to the copper clad laminate through an exposure and development process; S4, use chemical solution to etch away the copper foil not protected by the resist, leaving the designed circuit pattern, and plate a layer of metal on the copper foil to prevent oxidation and provide a good soldering surface; S5. Drill holes on both sides of the circuit board to achieve electrical connection between layers; S6. A thin layer of copper is plated in the hole by electroplating to increase the conductivity of the via hole; S7. Perform some surface treatment on the circuit board, and then perform functional testing and debugging to ensure the reliability of the circuit board; The screen printing device in S2 comprises a flip portion (1), the flip portion (1) comprises a rotating shaft (11), the rotating shaft (11) is connected to an output shaft (12) via a rotating groove provided on its circumferential surface for damping rotation, and four output shafts (12) are arranged and distributed in a circumferential array with the rotating shaft (11) as the center; A printing unit (2), the printing unit (2) comprising a clamping mechanism (21), the clamping mechanism (21) comprising a fixed frame (211), a side surface of the fixed frame (211) being fixedly connected to an output end of an output shaft (12), an inner side of the fixed frame (211) away from the output shaft (12) being fixedly connected to a magnetic block (212), an outer side of the magnetic block (212) being provided with a slide rail rod (213) that slides in contact with a slide groove on an inner wall of the fixed frame (211), two slide rail rods (213) being provided and symmetrically distributed with the magnetic block (212) as the center, a fixed block (214) being fixedly connected to a middle portion of the slide rail rod (213), and the fixed block (214) being connected to a right-angle block (216) that slides with an outer surface of the slide rail rod (213) via a spring group (215) provided on an outer side thereof; The output shaft (12) is provided with a bevel gear (13) on its circumferential outer surface near one end of the rotating shaft (11); a hollow column (14) is provided on the circumferential outer surface of the rotating shaft (11); a driving motor inside the hollow column (14) is transmission-connected to the bottom of the rotating shaft (11); a groove is provided at one end of the hollow column (14); a connection between the inner wall of the groove and the hollow column (14) is designed with an arc surface; a bevel tooth column (15) meshing with the tooth surface of the bevel gear (13) is provided on the outside of the rotating shaft (11) near the groove; a special-shaped groove (16) fitting with the top end of the hollow column (14) is provided on the circumferential outer surface of the output shaft (12); and the side of the special-shaped groove (16) is designed with an arc surface.

2. A precision printed circuit board processing technology according to claim 1, characterized in that: A triangle plate (217) is fixedly connected to one side of the right-angle block (216), and an electromagnet is provided at a port of the right-angle block (216). The printing unit (2) further comprises a screen printing mechanism (22), below which is provided a lifting mechanism (23) for cooperating with the screen printing mechanism (22) to print a circuit board, and the lifting mechanism (23) is symmetrically provided with a lifting platform (24) with the rotating shaft (11) as the center.

3. A precision printed circuit board processing process according to claim 2, characterized in that: The screen printing mechanism (22) comprises a screen plate (221), the screen plate (221) being slidably connected to a top frame (222) via a sliding rod fixedly connected to the top surface thereof, a side of the bottom surface of the top frame (222) away from the sliding rod being fixedly connected to a power distribution cabinet, a side edge of the screen plate (221) being fixedly connected to a connecting rod (223), and an end of the connecting rod (223) away from the screen plate (221) being fixedly connected to a pressing plate (224).

4. A precision printed circuit board processing process according to claim 3, characterized in that: The lifting mechanism (23) comprises a base (231), the upper surface of the base (231) is fixedly connected to a limiting frame (232), a side of the limiting frame (232) away from the base (231) is slidably connected to a lifting rod (233) via a square hole provided inside the limiting frame, one end of the lifting rod (233) close to the pressure plate (224) is fixedly connected to a supporting plate (234), the other end of the lifting rod (233) is rotatably connected to a rotating rod (235), one end of the rotating rod (235) away from the lifting rod (233) is rotatably connected to a lifting column (236) via a rotating shaft, and the rotating rod (235) is connected to a support frame fixedly connected to the upper surface of the base (231) via a shifting groove provided in the middle thereof.

5. A precision printed circuit board processing process according to claim 4, characterized in that: One end of the lifting column (236) away from the base (231) is fixedly connected to a bottom plate, an arc plate group (237) is arranged on the upper surface of the bottom plate, the other end of the arc plate group (237) is connected to a nail plate (238), the upper surface of the nail plate (238) is fixedly connected to nail pins (239), a plurality of nail pins (239) are arranged in an array, and a positioning piece (25) is arranged on the side of the nail plate (238), and four positioning pieces (25) are arranged.

6. A precision printed circuit board processing process according to claim 5, characterized in that: The positioning member (25) comprises a rotating seat (251), one side of the rotating seat (251) is fixedly connected to the side of the nail plate (238), the interior of the rotating seat (251) is rotatably connected to an L-shaped plate (252) via a shaft, and a torsion spring (253) connected to the interior of the L-shaped plate (252) is sleeved on the circumferential outer surface of the shaft, and a micro-nail (254) is arranged on the side of the L-shaped plate (252) away from the nail plate (238), and a plurality of micro-nail (254) are distributed in an array.

7. A precision printed circuit board processing process according to claim 6, characterized in that: The L-shaped plate (252) is provided with a silicone strip (255) perpendicular to the inner wall of the micro-nail (254), and a slot (256) is provided at the upper end of the silicone strip (255).

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