Method and device for repairing via hole of printed circuit board

Abstract

The invention relates to the technical field of printed circuit boards, and discloses a via hole repairing method and device of a printed circuit board, the via hole repairing method of the printed circuit board is applied to a control module of the via hole repairing device, and the via hole repairing device further comprises a moving module and a dispensing valve. The method comprises the steps that the defect type and the target position of a defect hole in via holes in a printed circuit board to be repaired are determined, and the printed circuit board to be repaired is a printed circuit board subjected to hole plugging treatment; based on the target position of the defect hole, controlling a moving module to move a dispensing valve to the position above the defect hole; and based on the defect type of the defect hole, controlling the dispensing valve to deposit a filling material to the defect hole so as to repair the to-be-repaired printed circuit board. According to the invention, the automatic, precise and differentiated repair of the bad plug hole can be effectively realized, and the repair efficiency and the repair quality are improved.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit boards, and in particular to a method and equipment for repairing via holes in a printed circuit board. Background Art

[0002] Printed circuit board (PCB) is the most basic and critical component in the electronics industry. In order to achieve electrical connection, vias are set on the PCB. The vias on the PCB are designed according to the device placement and routing requirements, and there is no fixed rule for the number and position of vias. In addition, the vias on the PCB are usually plugged with resin. The resin plugging process uses resin to plug the buried holes with copper plating on the inner hole wall, and then presses them together, and then copper plating the surface, which can effectively increase the routing density, prevent signal interference and improve the reliability of the circuit board.

[0003] During the via vacuum plugging process, due to impurities inside the hole, roughness of the hole wall, low vacuum in the vacuum chamber of the plugging equipment, insufficient printing resin or partial blockage of the printing stencil, the via plugging may have defects such as leaking, depression, bubbles in the hole, voids or incomplete filling, which will affect the long-term reliability during subsequent processing and use. At present, the defects in the via plugging process are mainly repaired manually, but manual repair has problems such as low repair efficiency and difficulty in ensuring repair consistency. Summary of the invention

[0004] In view of this, the present invention provides a method and device for repairing via holes of a printed circuit board, so as to improve the problems of low repair efficiency and difficulty in ensuring repair consistency.

[0005] In a first aspect, the present invention provides a method for repairing a via of a printed circuit board, which is applied to a control module of a via repair device, wherein the via repair device also includes a moving module and a dispensing valve, and the method includes: determining a defect type and a target position of a defective hole in a via on a printed circuit board to be repaired, wherein the printed circuit board to be repaired is a printed circuit board that has been plugged; based on the target position of the defective hole, controlling the moving module to move the dispensing valve to above the defective hole; based on the defect type of the defective hole, controlling the dispensing valve to deposit filling material into the defective hole to repair the printed circuit board to be repaired.

[0006] In an optional embodiment, based on the type of the defect hole, the dispensing valve is controlled to deposit filling material into the defect hole, including: determining a target filling amount required for the defect hole based on the defect type of the defect hole; and controlling the dispensing valve to deposit filling material into the defect hole until the filling amount of the filling material reaches the target filling amount.

[0007] In an optional embodiment, based on the defect type of the defect hole, the target filling amount required for the defect hole is determined, including: when the defect type of the defect hole is leakage, the target filling amount is determined based on the diameter of the defect hole, the thickness of the printed circuit board to be repaired and the minimum depression value; when the defect type of the defect hole is unfilled, the target filling amount is greater than or equal to 50% of the total volume of the via; when the defect type of the defect hole is bubbles, the target filling amount is greater than or equal to 25% of the total volume of the via.

[0008] In an optional embodiment, determining the defect type and target position of a defective hole among multiple via holes on a printed circuit board to be repaired includes: determining the defect type and target position of the defective hole based on a first detection result of an automatic optical inspection device.

[0009] In an optional embodiment, determining the defect type and target position of the defect hole based on the first detection result of the automatic optical detection device includes: determining the defect type and initial position of the defect hole based on the first detection result of the automatic optical detection device; determining the target position based on the initial position, the positioning point of the printed circuit board to be repaired, and the second detection result of the visual system. Preferably, the detection accuracy of the visual system is greater than the detection accuracy of the automatic optical detection device.

[0010] In an optional embodiment, before controlling the dispensing valve to deposit filling material into the defect hole based on the defect type of the defect hole, the method also includes: determining the distance from the dispensing valve to the defect hole by means of a distance measuring sensor; when the distance from the dispensing valve to the defect hole is less than or greater than a preset distance, controlling the moving module to move the dispensing valve so that the distance from the dispensing valve to the defect hole is a preset distance.

[0011] In an optional embodiment, after controlling the dispensing valve to deposit filling material into the defect hole based on the defect type of the defect hole, the method further includes: controlling a flipping mechanism to flip the printed circuit board to be repaired, returning to the step of determining the defect type and target position of the defect hole in the multiple vias on the printed circuit board to be repaired, and completing the repair of the defect hole on the other side of the printed circuit board to be repaired.

[0012] In an optional embodiment, the flipping mechanism includes a screw module, an air gripper and a turntable, the air gripper is used to clamp the printed circuit board to be repaired, the turntable is used to drive the air gripper to rotate, and the screw module is used to drive the printed circuit board to be repaired to move.

[0013] In a second aspect, the present invention provides a via repair device for a printed circuit board, the via repair device comprising a dispensing valve, a moving module and a control module; the control module is used to determine the defect type and target position of a defective hole among multiple vias on the printed circuit board to be repaired, wherein the printed circuit board to be repaired is a printed circuit board that has been plugged; the control module is also used to control the moving module to move the dispensing valve to above the defective hole based on the target position of the defective hole; the control module is also used to control the dispensing valve to deposit filling material into the defective hole based on the defect type of the defective hole to repair the printed circuit board to be repaired.

[0014] In an optional embodiment, the via repairing device further includes a visual system, and the visual system is used to collect a surface image of the printed circuit board to be repaired.

[0015] The via repair method, device and printed circuit board provided by the present invention have at least the following beneficial effects:

[0016] (1) The method for repairing a via hole of a printed circuit board provided by the present invention, after determining the defect type and target position of each defect hole, the control module controls the moving module to move the dispensing valve to the top of each defect hole in turn based on the target position, and controls the dispensing valve to deposit different amounts of filling materials to each defect hole based on the defect type, and performs differentiated repairs on each defect hole, thereby completing the repair of the printed circuit board to be repaired. The present invention can effectively realize the automation, precision and differentiated repair of PCB defective plugged holes through the mutual cooperation of the moving module, the control module and the dispensing valve, and the repair efficiency is 2 to 3 times that of manual repair, which can improve the repair quality and reduce the production cost of PCB.

[0017] (2) After determining the defect type of the defect hole, the present invention determines the target filling amount required for the defect hole based on the defect type of the defect hole, and then deposits the filling material into the defect hole based on the target filling amount, which can accurately control the amount of filling material, reduce secondary processing caused by improper filling, and improve repair efficiency. Moreover, repair based on the target filling amount can also reduce errors caused by human factors and improve the consistency and reliability of repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a structural block diagram of a via repair device for a printed circuit board according to an embodiment of the present invention;

[0019] Figure 2 is a schematic flow chart of a method for repairing a via hole of a printed circuit board according to an embodiment of the present invention;

[0020] Figure 3 is a schematic cross-sectional view of a via hole in a leak plugging condition according to an embodiment of the present invention;

[0021] Figure 4 is a schematic cross-sectional view of a via hole when one side is not filled according to an embodiment of the present invention;

[0022] Figure 5 is a schematic cross-sectional view of a via hole when both sides are not filled according to an embodiment of the present invention;

[0023] Figure 6 is a schematic cross-sectional view of a via hole in the case of bubbles in the hole according to an embodiment of the present invention;

[0024] Figure 7 is a schematic cross-sectional view of a via hole in the case of a pinhole-shaped bubble according to an embodiment of the present invention;

[0025] Figure 8 is a flow chart of another method for repairing a via hole of a printed circuit board according to an embodiment of the present invention;

[0026] Fig. 9 is a schematic diagram of a minimum concavity value according to an embodiment of the present invention;

[0027] Fig.10 is a schematic flow chart of another method for repairing a via hole of a printed circuit board according to an embodiment of the present invention;

[0028] Fig.11 2 is a schematic structural diagram of a flipping mechanism according to an embodiment of the present invention.

[0029] Figure numerals: 110, control module; 120, moving module; 130, dispensing valve; 140, turning mechanism; 141, screw module; 142, air claw; 143, turntable; 310, through hole; 320, resin material. DETAILED DESCRIPTION

[0030] 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0031] As electronic products gradually develop towards being lighter, smaller and thinner, the demand for high-precision, high-density and high-difficulty PCB boards increases, and the PCB manufacturing process becomes more and more complicated, so the plugging process comes into being. Before the resin plugging process became popular, PCBs generally adopted the green oil plugging process with a relatively simple process, but the green oil plugging process will shrink after curing, and it is easy to cause the problem of air blowing in the hole, which cannot meet the user's high fullness requirements.

[0032] The resin plugging process uses resin to plug the buried vias of the inner layer high-density interconnection (HDI) before pressing. It can not only avoid the problems caused by green oil plugging, but also balance the contradiction between the thickness of the pressed dielectric layer and the inner layer HDI buried via filling design. It is widely used in high-frequency boards and HDI boards.

[0033] Specifically, the resin plugging process can be as follows: for the area of ​​the PCB that needs to be plugged with resin, the corresponding pad and printing screen are made, wherein the area to be plugged on the pad is hollowed out to avoid it, and the area to be plugged on the printing screen is opened to realize regional selective plugging; then, the pad, PCB and printing screen placed in sequence from bottom to top are put into the vacuum screen printing plugging machine, the scraper is pressed down, and the ink leaks from the opening area of ​​the upper printing screen into the PCB via, wherein the absolute vacuum value of the vacuum chamber is below 50Pa.

[0034] Compared with the traditional screen printing plugging process, the product is in a vacuum state during this process, which can effectively reduce defects such as bubbles. However, in the actual production process, due to impurities inside the via, roughness of the hole wall, low vacuum in the vacuum chamber of the plugging equipment, insufficient printing resin or partial blockage of the printing screen, the via plugging will have defects such as leakage, depression, bubbles in the hole, and voids. If one via is not filled or has bubbles, the subsequent process may cause delamination or board explosion. Therefore, it is necessary to ensure that the resin in each via on the PCB board is well filled.

[0035] At present, defects in the via plugging process are mainly repaired manually. Specifically, the repairer first confirms whether the via needs to be repaired through a magnifying glass. If it is determined that it needs to be repaired, the repairer uses a metal needle, dips a small amount of special resin material for via plugging repair, and then pokes the metal needle into the via to be repaired. At the same time, a hot air gun is used to blow the special resin material from the metal needle into the via to be repaired, and then the repaired PCB is placed in a tunnel heating furnace to complete the resin curing.

[0036] However, as the interconnection density of PCB increases, the size of vias is getting smaller and smaller, the board thickness is getting larger and larger, and the number of vias on the PCB can reach tens of thousands. The probability of bad vias after the plugging process increases, and the location of bad vias is scattered and irregular, resulting in low efficiency of manual repair. In addition, manual repair requires special training for repair personnel, which takes a long time and the consistency of repair is difficult to ensure.

[0037] In view of this, the present invention provides a method for repairing vias of a printed circuit board, which can use a via repair device to complete the repair of defective vias, realize the automated repair of defective vias of a PCB, improve the repair efficiency of defective vias and ensure the consistency of the repair, thereby improving the repair quality and reducing the repair cost.

[0038] First, the structure of the PCB via repair device provided by the present invention is briefly described below in conjunction with the accompanying drawings.

[0039] like Figure 1 As shown, the PCB via repair device provided by the present invention includes a control module 110, a moving module 120 and a dispensing valve 130.

[0040] Specifically, the moving module 120 is used to drive the dispensing valve 130 to move in the X direction, the Y direction and the Z direction. The dispensing valve 130 is connected to the feeding module. The dispensing valve 130 is used to spray the filling material. The specific functions of the control module 110 are described in detail below.

[0041] Exemplarily, the mobile module 120 and the dispensing valve 130 may be the mobile module and the dispensing valve of a printing device, and the control module 110 may be a controller or processor of the printing device, or an electronic device such as a computer or a computer. The printing device is a conventional printing device in the art and will not be described in detail here.

[0042] The present invention does not limit the specific type of the dispensing valve 130. For example, the dispensing valve can be a piezoelectric valve, a striker valve, an inkjet valve, or a direct writing valve.

[0043] According to an embodiment of the present invention, an embodiment of a via repair method for a printed circuit board is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in the above-mentioned control module, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0044] In this embodiment, a method for repairing a via hole of a printed circuit board is provided, which can be used in the control module 110 described above. Figure 2 FIG. 1 is a flow chart of a method for repairing a via hole of a printed circuit board according to an embodiment of the present invention. Figure 2 As shown, the method comprises the following steps:

[0045] Step S201, determining the defect type and target position of a defective hole among a plurality of via holes on a printed circuit board to be repaired.

[0046] Among them, the printed circuit board to be repaired is a printed circuit board that has undergone plugging treatment, and the defective hole is a via hole that is filled with defects after plugging treatment. The defect types include but are not limited to missing plugs, unfilled holes and bubbles, etc. Unfilled holes can be further divided into double-sided unfilled holes and single-sided unfilled holes, and bubbles can be further divided into intra-hole bubbles and pinhole-shaped bubbles.

[0047] Specifically, the cross-sectional schematic diagram of the via hole in the case of leakage plugging can be as follows: Figure 3As shown in FIG. 1 , the leaky plug refers to the fact that the resin material 320 is not filled in the via hole 310 after the via plugging process. The cross-sectional schematic diagram of the via hole when it is not filled can be as follows: Figure 4 or Figure 5 As shown, Figure 4 Indicates that one side is not filled. Figure 5 It indicates the situation where both sides are not filled. Single-side unfilled means that one end of the via 310 is not filled with the resin material 320 after the plugging process. Double-side unfilled means that both ends of the via 310 are not filled with the resin material 320 after the plugging process.

[0048] The cross-sectional diagram of the via in the case of bubbles can be shown as follows: Figure 6 or Figure 7 As shown, Figure 6 Indicates the situation of bubbles in the hole. Figure 7 Indicates the situation of pinhole-shaped bubbles. The bubble in the hole refers to the presence of an opening at one end of the via 310 after the via plugging process, and the first width d1 of the opening is greater than the second width d2. The pinhole-shaped bubble refers to the presence of an opening at one end of the via 310 after the via plugging process, and the first width d1 of the opening is less than or equal to the second width d2. Among them, the first width refers to the maximum width of the opening, and the second width refers to the width of the opening at the end face of the via.

[0049] That is, when bubbles exist in the via hole after the plugging process, if d1>d2, the bubbles are intra-hole bubbles; if d1≤d2, the bubbles are pinhole bubbles.

[0050] Specifically, the present invention does not limit the design size of the PCB. For example, the length and width of the PCB can both be 10 inches, the length of the PCB can also be 36 inches, the width of the PCB can also be 28 inches, and so on.

[0051] Exemplarily, the defect type and target position may be determined based on an automated optical inspection (AOI) device.

[0052] Specifically, the AOI equipment includes multiple cameras, through which the global image of the PCB can be obtained. By comparing the obtained global image with the standard filling image, it can be determined whether the via is a defective hole. In the case of a defective hole, the defect type can be determined based on the pixel difference between the global image and the standard filling image in the area corresponding to the defective hole. After determining the defect type, the position of the defective hole on the PCB (i.e., the target position) can be determined based on the positioning (MARK) point of the PCB in the global image and the design information of the PCB. Among them, the design information of the PCB may include basic information such as the thickness, length, width and aperture of the PCB, and the target position may be the coordinate value of the center point of the defective hole.

[0053] Exemplarily, the repair personnel may also input the defect type and target position of the defect hole into the control module, so that the control module determines the defect type and target position of the defect hole.

[0054] Step S202, based on the target position of the defect hole, controlling the moving module to move the dispensing valve to above the defect hole.

[0055] Specifically, after determining the target position of the defect hole, the control module can determine the moving path based on the target position and the current position of the dispensing valve, and generate a control instruction based on the moving path to control the moving module to move according to the moving path so that the dispensing valve is located above the defect hole. The dispensing valve being located above the defect hole can mean that the dispensing position of the dispensing valve is aligned with the preset position of the defect hole (for example, the center of the defect hole).

[0056] For example, if the current position of the dispensing valve is (10mm, 20mm) and the target position is (24mm, 12mm), the moving path can be 14mm in the positive direction of the X axis and 8mm in the negative direction of the Y axis.

[0057] Step S203, based on the defect type of the defect hole, controlling the dispensing valve to deposit a filling material into the defect hole to repair the printed circuit board to be repaired.

[0058] Specifically, after determining the defect type of the defect hole, the discharge amount of the dispensing valve (i.e., the filling amount required for the defect hole) can be determined based on the corresponding relationship between the defect type and the filling amount, and after the dispensing valve is located above the defect hole, the dispensing valve is controlled to deposit filling material to the defect hole to improve the filling state of the defect hole so that the defect hole is well filled (e.g., the via hole is completely filled with the filling material). The filling material includes but is not limited to resin material.

[0059] Exemplarily, the correspondence between the defect type and the filling amount can be determined by a designer based on experience and pre-configured in the control module.

[0060] In the method for repairing a via hole of a printed circuit board provided in this embodiment, after determining the defect type and target position of each defect hole, the control module controls the moving module to move the dispensing valve to the top of each defect hole in turn based on the target position, and controls the dispensing valve to deposit different amounts of filling materials to each defect hole based on the defect type, and performs differentiated repairs on each defect hole, thereby completing the repair of the printed circuit board to be repaired. The present invention can effectively realize the automation, precision and differentiated repair of PCB defective plug holes through the mutual cooperation of the moving module, the control module and the dispensing valve, and the repair efficiency is 2 to 3 times that of manual repair, which can improve the repair quality and reduce the production cost of PCB.

[0061] In this embodiment, a method for repairing a via hole of a printed circuit board is provided, which can be used for the above-mentioned control module. Figure 8 FIG. 1 is a flow chart of another method for repairing a via hole of a printed circuit board according to an embodiment of the present invention. Figure 8 As shown, the method comprises the following steps:

[0062] Step S801, determining the defect type and target position of a defective hole among a plurality of via holes on a printed circuit board to be repaired.

[0063] For details, please see Figure 2 Step S201 of the illustrated embodiment will not be described in detail here.

[0064] Step S802, based on the target position of the defect hole, controlling the moving module to move the dispensing valve to above the defect hole.

[0065] For details, please see Figure 2 Step S202 of the illustrated embodiment will not be described in detail here.

[0066] Step S803, based on the defect type of the defect hole, controlling the dispensing valve to deposit a filling material into the defect hole to repair the printed circuit board to be repaired.

[0067] Specifically, the above step S803 includes:

[0068] Step S8031, determining a target filling amount required for the defect hole based on the defect type of the defect hole.

[0069] Among them, the target filling amount refers to the amount of filling material required for the defect hole to reach the standard state. The standard state can be defined by the designer, and the target filling amount can be obtained through volume characterization.

[0070] Exemplarily, when the defect type of the defect hole is leak plugging, the target filling amount is determined based on the diameter of the defect hole, the thickness of the printed circuit board to be repaired, and the minimum recess value.

[0071] Among them, the minimum concave value is the minimum concave value required by the PCB production inspection standard, such as Fig. 9 As shown, the minimum recess value h specifically refers to the distance from the top of the plug filling material to the hole opening of the via.

[0072] Specifically, after determining the diameter of the defect hole, the thickness of the printed circuit board to be repaired, and the minimum recess value, the target filling amount can be determined by the following formula (1).

[0073] V1=V×(1-h / H)×100% (1)

[0074] Among them, V1 represents the volume of the filling material, V represents the total volume of the via, h represents the minimum depression value, and H represents the thickness of the printed circuit board to be repaired, such as Fig. 9 As shown. V = S × H, S represents the cross-sectional area of ​​the via, S = π × (D / 2) 2 , D represents the diameter of the defect hole, such as Fig. 9 shown.

[0075] Specifically, when the defect type of the defect hole is leakage, the dispensing valve sprays a filling material greater than or equal to a volume V1 into the defect hole, that is, the target filling amount is greater than or equal to V1.

[0076] When the defect type of the defect hole is not filled, the target filling amount is controlled to be greater than or equal to 50% of the total volume of the via hole. That is, when the defect type of the defect hole is not filled, the dispensing valve sprays a filling material greater than or equal to V×50% into the defect hole, and the target filling amount is greater than or equal to V×50%.

[0077] When the defect type of the defect hole is a bubble, the target filling amount is controlled to be greater than or equal to 25% of the total volume of the via hole. That is, when the defect type of the defect hole is a bubble, the dispensing valve sprays a filling material greater than or equal to V×25% into the defect hole, and the target filling amount is greater than or equal to V×25%.

[0078] Step S8032, controlling the dispensing valve to deposit filling material into the defective hole until the filling amount of the filling material reaches the target filling amount.

[0079] Specifically, after determining the target filling amount, the control module controls the dispensing valve to inject the target filling amount of filling material into the defective hole, and performs a curing process to complete the repair of the defective hole.

[0080] In this embodiment, after determining the defect type of the defect hole, the target filling amount required for the defect hole is determined based on the defect type of the defect hole, and then the filling material is deposited into the defect hole based on the target filling amount, so that the amount of filling material can be accurately controlled, and the secondary processing caused by improper filling can be reduced, thereby improving the repair efficiency. Moreover, the repair based on the target filling amount can also reduce the error caused by human factors and improve the consistency and reliability of the repair.

[0081] In this embodiment, a method for repairing a via hole of a printed circuit board is provided, which can be used for the above-mentioned control module. Fig.10 FIG. 1 is a flow chart of another method for repairing a via hole of a printed circuit board according to an embodiment of the present invention. Fig.10 As shown, the method comprises the following steps:

[0082] Step S1001, determining the defect type and target position of the defect hole based on a first detection result of an automatic optical inspection device.

[0083] The first detection result is the defect type of the defect hole determined by the AOI device and the target position of the defect hole determined by the AOI device.

[0084] In some implementations, the control module directly determines the defect type and target position in the first detection result as the defect type and target position of the defective hole.

[0085] In other embodiments, in order to improve the position accuracy of the defective hole, the via repairing device further includes a visual system, and the above step S1001 includes:

[0086] Step S10011, determining the defect type and initial position of the defect hole based on the first detection result of the automatic optical inspection device.

[0087] Step S10012, determining the target position based on the initial position, the positioning point of the printed circuit board to be repaired and the second detection result of the visual system.

[0088] The detection accuracy of the visual system is greater than the detection accuracy of the automatic optical inspection device, and the second detection result includes a global image of the printed circuit board to be repaired, and the global image includes the positioning point. The visual system also includes multiple cameras, and the global image is obtained by the multiple cameras.

[0089] Specifically, the position of the printed circuit board to be repaired on the carrier of the via repair device may deviate. After the defect type of the defective hole is determined based on the first detection result, the target position is determined by calibrating the initial position through the positioning points in the global image.

[0090] In some optional embodiments, the vision system further includes a light source, which is used to provide stable and uniform illumination for the camera, so that features on the PCB can be clearly displayed, thereby improving the accuracy of the global image acquired by the camera.

[0091] Specifically, the light source can be a red, green, and blue (RGB) three-color light source. Light sources of different colors can highlight different defects. The use of RGB three-color light sources can achieve the effect of one-time simultaneous detection, thereby improving the accuracy of the detection results.

[0092] Step S1002, based on the target position of the defect hole, controlling the moving module to move the dispensing valve to above the defect hole.

[0093] For details, please see Figure 2 Step S202 of the illustrated embodiment will not be described in detail here.

[0094] Step S1003, determining the distance from the dispensing valve to the defect hole by using a distance measuring sensor.

[0095] Exemplarily, the distance measuring sensor includes but is not limited to a laser distance measuring sensor. The distance measuring sensor determines the distance in the same manner as a conventional distance measuring manner, which will not be described herein.

[0096] Step S1004, when the distance from the dispensing valve to the defect hole is less than or greater than the preset distance, control the moving module to move the dispensing valve so that the distance from the dispensing valve to the defect hole is the preset distance.

[0097] The preset distance is a fixed value, which can be determined by designers based on experience. The preset distance can also be a range. For example, the preset distance can be any value between a preset value of -1 mm and a preset value of +1 mm.

[0098] Specifically, when the distance from the dispensing valve to the defect hole is less than the preset distance, the control moving module moves the dispensing valve upward, and the moving distance is the difference between the preset distance and the distance from the dispensing valve to the defect hole; when the distance from the dispensing valve to the defect hole is greater than the preset distance, the control moving module moves the dispensing valve downward, and the moving distance is the difference between the distance from the dispensing valve to the defect hole and the preset distance.

[0099] If the distance from the dispensing valve to the defect hole is far (greater than the preset distance), the filling material may be dispersed when it reaches the defect hole, resulting in uneven dispensing amount and affecting the accuracy; if the distance from the dispensing valve to the defect hole is close (less than the preset distance), the extrusion pressure may be insufficient and the glue cannot flow out smoothly, resulting in insufficient dispensing amount or glue breakage.

[0100] Step S1005 , based on the defect type of the defect hole, controlling the dispensing valve to deposit a filling material into the defect hole to repair the printed circuit board to be repaired.

[0101] For details, please see Figure 8 Step S803 of the illustrated embodiment will not be described in detail here.

[0102] Step S1006, controlling the flipping mechanism to flip the printed circuit board to be repaired.

[0103] Specifically, the via repair device also includes a flipping mechanism, and the two ends of the via respectively correspond to two opposite surfaces of the PCB (recorded as the first surface and the second surface). After completing the repair of the defective hole on one surface of the PCB (such as the first surface), the printed circuit board to be repaired is flipped 180° by the flipping mechanism, so that the other surface of the PCB (such as the second surface) faces the dispensing valve, and the above steps S1001 to S1005 are re-executed to complete the repair of the defective hole on the other side of the PCB.

[0104] For example, Fig.11 As shown, the flip mechanism 140 includes a screw module 141, an air gripper 142 and a turntable 143. The air gripper 142 is used to clamp the printed circuit board to be repaired, the turntable 143 is used to drive the air gripper 142 to rotate, and the screw module 141 is used to drive the printed circuit board to be repaired to move.

[0105] Specifically, after determining that flipping is required, the printed circuit board to be repaired on the carrier is first clamped by the air gripper 142, and then the printed circuit board to be repaired is taken away from the carrier by the lead screw module 141, and then the turntable 143 flips the air gripper 142 and the printed circuit board to be repaired clamped by the air gripper 142, so that the other surface of the printed circuit board to be repaired faces the dispensing valve. Then, the printed circuit board to be repaired is placed on the carrier by the lead screw module 141, and the air gripper 142 releases the printed circuit board to be repaired, and the lead screw module 141 moves the air gripper 142 to move the air gripper 142 away from the carrier.

[0106] In this embodiment, after the dispensing valve is moved to the top of the defect hole, the distance from the dispensing valve to the defect hole is determined by a distance measuring sensor. When the distance from the dispensing valve to the defect hole is less than or greater than a preset distance, the moving module is controlled to move the dispensing valve so that the distance from the dispensing valve to the defect hole is the preset distance to ensure the filling quality.

[0107] The following takes defective holes on both sides of a PCB as an example to describe in detail the via hole repair method for a printed circuit board provided by the present invention.

[0108] First, the resin for repairing the via hole is loaded into the material tube, and the material tube is loaded on the dispensing valve, and the propulsion air path is connected. At the same time, the PCB is fixed on the carrier, and the first surface of the PCB faces the dispensing valve. The PCB can be fixed on the carrier by a vacuum adsorption device.

[0109] Then, the visual system is used to grab the positioning points on the PCB, and the design information of the PCB and the first detection result of the AOI equipment are imported. After that, the second detection result is determined by the visual system, and the defect type and target position of the first surface defect hole are determined based on the first detection result and the second detection result.

[0110] Then, based on the target position, the mobile module is controlled to move the dispensing valve above the defective hole and a laser ranging sensor is used to perform a height scan on the surface of the defective hole to determine the distance from the dispensing valve to the defective hole. When the distance from the dispensing valve to the defective hole is not within a preset distance range, the mobile module is controlled to move the dispensing valve so that the distance from the dispensing valve to the defective hole is within a preset distance range.

[0111] After determining the specific position of the dispensing valve, if the defect type of the defective hole is leakage, the dispensing valve sprays a resin material of no less than volume V1 into the hole; if the defect type of the defective hole is unfilled, the dispensing valve sprays a resin material of no less than 50% of the total volume of the via into the hole; if the defect type of the defective hole is bubbles, the dispensing valve sprays a resin material of no less than 25% of the total volume of the via into the hole, and cures to complete the repair of the corresponding defective hole.

[0112] After all defect holes on the first surface are repaired through the above steps, the flipping mechanism is controlled to flip the PCB 180° so that the second surface faces the dispensing valve, and then the above steps are repeated until all defect holes on the second surface are repaired.

[0113] The control module in this embodiment is presented in the form of a functional unit, where the unit refers to an application specific integrated circuit (ASIC), a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0114] The embodiment of the present invention also provides a computer device, which is equivalent to the above-mentioned control module, and the computer device includes: one or more processors, memory, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. The various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system).

[0115] The processor may be a central processing unit, a network processor or a combination thereof. The processor may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0116] The memory stores instructions executable by at least one processor, so that the at least one processor executes the method shown in the above embodiment.

[0117] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0118] The memory may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid state drive; the memory may also include a combination of the above types of memory.

[0119] The computer device also includes a communication interface, which is used for the computer device to communicate with other devices or a communication network.

[0120] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0121] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0122] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0123] In the description of this specification, the description with reference to the terms "this embodiment", "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0124] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0125] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the present invention.

Claims

1. A method for repairing a via hole in a printed circuit board, characterized in that: A control module applied to a via repair device, wherein the via repair device further comprises a moving module and a dispensing valve, and the method comprises: Determining the defect type and target position of a defect hole in a via hole on a printed circuit board to be repaired, wherein the printed circuit board to be repaired is a printed circuit board that has been plugged; Based on the target position of the defect hole, controlling the moving module to move the dispensing valve to above the defect hole; Based on the defect type of the defect hole, the dispensing valve is controlled to deposit a filling material into the defect hole to repair the printed circuit board to be repaired.

2. The method according to claim 1, characterized in that The step of controlling the dispensing valve to deposit a filling material to the defect hole based on the defect type of the defect hole comprises: Determining a target filling amount required for the defect hole based on the defect type of the defect hole; The dispensing valve is controlled to deposit the filling material to the defect hole until the filling amount of the filling material reaches the target filling amount.

3. The method according to claim 2, characterized in that The step of determining a target filling amount required for the defect hole based on the defect type of the defect hole comprises: When the defect type of the defect hole is leak plugging, the target filling amount is determined based on the diameter of the defect hole, the thickness of the printed circuit board to be repaired, and the minimum concavity value; When the defect type of the defect hole is unfilled, the target filling amount is greater than or equal to 50% of the total volume of the via hole; When the defect type of the defective hole is a bubble, the target filling amount is greater than or equal to 25% of the total volume of the via hole.

4. The method according to any one of claims 1 to 3, characterized in that The method of determining the defect type and target position of a defect hole among a plurality of via holes on a printed circuit board to be repaired comprises: Based on the first inspection result of the automatic optical inspection device, the defect type and the target position of the defective hole are determined.

5. The method according to claim 4, characterized in that The step of determining the defect type and target position of the defect hole based on the first detection result of the automatic optical inspection device comprises: Determining a defect type and an initial position of the defect hole based on a first detection result of an automatic optical inspection device; The target position is determined based on the initial position, the positioning point of the printed circuit board to be repaired and the second detection result of the vision system.

6. The method according to any one of claims 1 to 3, characterized in that Before controlling the dispensing valve to deposit a filling material to the defect hole based on the defect type of the defect hole, the method further includes: Determine the distance from the dispensing valve to the defect hole by using a distance measuring sensor; When the distance from the dispensing valve to the defect hole is less than or greater than a preset distance, the moving module is controlled to move the dispensing valve so that the distance from the dispensing valve to the defect hole is the preset distance.

7. The method according to any one of claims 1 to 3, characterized in that After controlling the dispensing valve to deposit a filling material into the defect hole based on the defect type of the defect hole, the method further includes: The flipping mechanism is controlled to flip the printed circuit board to be repaired, and the step of determining the defect type and target position of the defect hole in the plurality of via holes on the printed circuit board to be repaired is returned to complete the repair of the defect hole on the other side of the printed circuit board to be repaired.

8. The method according to claim 7, characterized in that The flipping mechanism includes a screw module, an air gripper and a turntable, wherein the air gripper is used to clamp the printed circuit board to be repaired, the turntable is used to drive the air gripper to rotate, and the screw module is used to drive the printed circuit board to be repaired to move.

9. A via repair device for a printed circuit board, characterized in that: The via repair device includes a dispensing valve, a moving module and a control module; The control module is used to determine the defect type and target position of a defect hole among a plurality of via holes on a printed circuit board to be repaired, wherein the printed circuit board to be repaired is a printed circuit board that has been plugged; The control module is further used to control the moving module to move the dispensing valve to above the defective hole based on the target position of the defective hole; The control module is further used to control the dispensing valve to deposit filling material into the defect hole based on the defect type of the defect hole, so as to repair the printed circuit board to be repaired.

10. The via repairing device for a printed circuit board according to claim 9, characterized in that: The via repairing device further comprises a visual system, and the visual system is used to collect the surface image of the printed circuit board to be repaired.

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