A method for repairing circuit boards using point induction heating

Abstract

The present invention discloses a circuit board repair method with fixed-point induction heating, which comprises the steps of S1: loading, S2: induction heating desoldering: moving the circuit board to an induction heating station according to actual coordinate parameters of the circuit board and the part to be repaired, desoldering the circuit board by an induction heating source, S3: applying solder or flux, S4: taking new components or chips, and S5: solid crystal welding. Compared with the prior art, the repair method provided by the present invention has the advantages of sufficient heat, strong controllability of heat source, adaptability to desoldering or welding requirements of components with a wide size range, good ability to achieve the expected heating effect, accurate positioning, stable operation, and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of precision machining, and in particular relates to a circuit board repair method. Background Art

[0002] Solder is applied to designated locations on a substrate, the corresponding component or chip is placed there, and the solder is heated using a specified heating method to melt it. After the solder cools and solidifies, the component or chip's legs are bonded to the corresponding pads, creating a conductive connection. This processing method is widely used in the field of circuit board manufacturing. However, as the manufacturing technology of components and chips has advanced, the size of components and chips has become smaller and smaller, and the corresponding requirements for circuit board manufacturing technology have also become more precise and stringent.

[0003] After processing and forming a circuit board, individual components or chips may be damaged, offset, missing, or detached, requiring partial repair. When this happens, the corresponding location on the substrate must be reheated to melt the solder, remove the damaged component or chip, and then re-solder a new, fully functional component or chip. During the circuit board repair process, due to the small size of individual components or chips and their high processing requirements, manual removal is not practical. Summary of the Invention

[0004] To solve the above problems, the purpose of the present invention is to provide a circuit board repair method with fixed-point induction heating, which uses a fully automated process and is based on the principle of induction heating to remove faulty components from circuit boards with local faults, replace them with new components, and repair the circuit board.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A circuit board repair method using fixed-point induction heating, the method comprising:

[0007] S1: Loading: Set up a loading platform with X-axis and Y-axis freedom, obtain the actual coordinate parameters of the circuit board and the part to be reworked, and place the circuit board to be reworked on the loading platform;

[0008] S2: Induction heating desoldering: The circuit board is moved to the induction heating station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the circuit board is desoldered by the induction heating source;

[0009] S3: Applying solder or flux: The desoldered circuit board is moved to the fluxing station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the fluxer reapplies solder and / or flux to the circuit board;

[0010] S4: Get new components or chips: while applying solder or flux, grab new components with corresponding functions;

[0011] S5: Die bonding: Based on the coordinate parameters of the circuit board and the part to be repaired, the new component is placed on the circuit board that has been re-applied with solder and / or flux. The circuit board is moved to the induction heating station and the circuit board is soldered by the induction heating source to complete the repair.

[0012] Among them, S1 is specifically:

[0013] S11: Perform AOI inspection on the circuit board to obtain the ideal coordinate parameters of the circuit board and the parts that need to be repaired;

[0014] S12: Setting a loading platform with X-axis and Y-axis freedom, placing the circuit board to be repaired on the loading platform, and transmitting ideal coordinate parameters of the circuit board and the part to be repaired to the loading platform;

[0015] S13: The camera is dispatched to photograph the circuit board from above the loading platform, and the photographed circuit board image is analyzed to identify and locate the marking points on the circuit board. Based on the located marking points on the circuit board, the ideal coordinate parameters of the circuit board and the parts requiring repair are superimposed on the current processing process to obtain the actual coordinate parameters of the circuit board and the parts requiring repair during the current processing process.

[0016] Among them, S2 is specifically:

[0017] S21: An induction heating source is provided which is fixed in the X-axis and Y-axis directions and has only a degree of freedom in the Z-axis direction, and the position where the induction heating is applied to the external workpiece is defined as the induction heating station;

[0018] S22: Based on the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform moves the circuit board to the induction heating station;

[0019] S23: Detect the substrate thickness of the current circuit board and the size and height data of the components at the location requiring rework;

[0020] S24: adjusting the height of the induction heating source along the Z-axis direction according to the current substrate thickness of the circuit board and the size and height of the components at the location to be repaired, and controlling the alternating magnetic field generated by the induction heating source to cover the location to be repaired, thereby melting the solder;

[0021] S25: Recycle and remove loose original components;

[0022] S26: Dispatching the induction heating source to continuously heat the soldering pads on the circuit board and the residual tin layer on the soldering pads to level the soldering pads;

[0023] S27: After desoldering, the camera is dispatched to shoot the exposed pads from above the current circuit board.

[0024] Among them, S3 is specifically:

[0025] S31: setting a tinning head or a flux applying head with freedom in the X-axis direction and the Z-axis direction, and setting the real-time tin outlet of the tinning head or the real-time flux outlet of the flux applying head as the fluxing station;

[0026] S32: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform and the tinning head or flux application head move simultaneously to move the desoldering circuit board to the fluxing station, and allow the tinning head or flux application head to move downward along the Z-axis direction to re-apply solder or flux to the pads on the circuit board.

[0027] Among them, S4 is specifically:

[0028] S41: new components that are functionally intact and correspond to the original components on the circuit board are classified and stored;

[0029] S42: While applying solder or flux, dispatch a camera to capture the classified and stored new components, locate each new component based on the captured image, obtain the specific coordinates of the new component required for the current rework, and select and capture the new component that has the same functional model as the original component removed by desoldering;

[0030] S43: dispatching the camera to shoot the captured new component from below, analyzing the captured image of the new component, and identifying the position of the pad of the captured new component;

[0031] S43: Compare the pad posture of the new component currently being grasped with the actual coordinate parameters of the circuit board and the part requiring rework, and analyze whether the pad posture of the new component currently being grasped is consistent with the original pad posture at the part requiring rework. If there is a deviation between the two, adjust the grasping posture until the two postures are consistent.

[0032] Furthermore, S43 is specifically:

[0033] S431: Acquire the image of the exposed pad captured in step S27, and analyze the location of the pad at the location where desoldering has been completed on the current circuit board, the number of pads, the orientation of each pad, and the distribution of different pads on the circuit board;

[0034] S432: Acquire the image of the new component captured in step S42, and analyze the pad distribution of the new component currently captured from the image;

[0035] S433: Compare the setting orientation of a single pad in the pad at the position where desoldering has been completed in the current circuit board, the distribution of different pads on the circuit board with the pad distribution of the new component currently being grasped. If the two are consistent, jump to S5; if the two are inconsistent, twist the grasping angle of the new component and adjust the grasping posture of the new component until the two are consistent.

[0036] Among them, S5 is specifically:

[0037] S51: Based on the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform is controlled to move the circuit board closer to the new component, and the new component is placed on the circuit board that has been re-applied with solder and / or flux;

[0038] S52: moving the pads of the circuit board to which solder and / or flux have been reapplied to the induction heating station according to actual coordinate parameters of the circuit board and the part to be repaired;

[0039] S53: Allow the induction heating source to move downward along the Z-axis direction, and control the alternating magnetic field generated again at the induction heating source. The alternating magnetic field induction heats the pad, the metal pad of the new component, and the reapplied solder to solder the new component to the circuit board.

[0040] The advantages of the present invention are: compared with the prior art, the repair method provided by the present invention has the following beneficial effects:

[0041] Sufficient heat, strong controllability of the heat source, adaptability to the desoldering or welding requirements of components in a wide range of sizes, and the ability to achieve the expected heating effect: In the rework method provided in this application, an induction heating source is selected as the heat source for welding or desoldering. Due to the mature development of induction heating technology, compared with resistance heat sources or laser heat sources, the induction heating source can generate a sufficiently high temperature while the key parameters such as the amount of heat generated and the location where the heat is generated can also be calculated in detail based on parameters such as the current size of the alternating current, the alternating frequency, the shape of the induction heating source, and the distance between the induction heating source and the circuit board. The final welding result is more controllable.

[0042] Accurate positioning and stable operation: For each component that needs to be reworked on each circuit board, it undergoes triple positioning in the rework method provided in this application: AOI detection is used to obtain the ideal coordinate parameters of the circuit board and the part that needs to be reworked as the first repositioning measure. After the first repositioning measure, the specific, digital appearance parameters of the circuit board, the specific position of each component on the circuit board, the specific position coordinates of the faulty component that needs to be reworked on the circuit board, its component installation posture and other parameters can be obtained; secondly, after the circuit board is placed on the loading platform, the camera is used to capture the mark points to obtain the actual coordinate parameters of the circuit board and the part that needs to be reworked. As a second re-positioning measure, after the second re-positioning measure, the ideal coordinate system originally established after AOI inspection can be superimposed with the actual circuit board, guiding the actual coordinates and posture of the parts that need to be repaired in the subsequent processing process; finally, after grabbing the new component, the posture of the pads in the new component is captured and analyzed by the camera, and the actual posture of the pads of the new component is adjusted to make it superimposed with the actual circuit board, ensuring that each processing component is accurately aligned with the required position, and can accurately process the faulty parts while ensuring that the pads of the new component can be accurately aligned with the circuit board, and the new component can be accurately soldered to the original pads.

[0043] High processing efficiency: During the implementation of the rework method provided in this application, the soldering process and the process of grabbing new components are carried out simultaneously. When the tinning head or flux application head reapplies solder or flux to the circuit board that has been desoldered, the new component has been taken out and the posture has been adjusted. Then the circuit board and the new component move at the same time, approach each other, and meet and align at the fastest speed to complete the solid crystal welding. Different components cooperate with each other in the entire processing process to efficiently complete the circuit board rework work. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a device for implementing the circuit board rework method of fixed-point induction heating provided in the specific implementation method, wherein A is a loading platform, which is mainly used to specifically perform the S1 loading step and the work of transporting the circuit board to be repaired in other steps; B is an induction heating source, which is mainly used to specifically perform the welding process in S2 induction heating desoldering and S5 solid crystal welding; C is a fluxer, which is mainly used to specifically perform the S3 step of applying solder or flux; D is a crystal retrieval machine, which is mainly used to specifically perform the S4 step of taking new components or chips and the process of transporting and placing components in S5.

[0045] Figure 2 It is a flow chart of a circuit board repair method using fixed-point induction heating provided in a specific embodiment. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] To achieve the above object, the technical solution of the present invention is as follows:

[0048] See also Figure 1-2 .

[0049] In this specific embodiment, a circuit board repair method with fixed-point induction heating is provided. The component repair machine is used in Mini LED or Micro LED displays. When a local fault occurs on the display circuit board, it is necessary to remove the faulty single R, G, B chip and then re-weld a new R, G, B chip with the same function as the original R, G, B chip.

[0050] The method is:

[0051] S1: Loading: Set up a loading platform with X-axis and Y-axis freedom, obtain the actual coordinate parameters of the circuit board and the part to be reworked, and place the circuit board to be reworked on the loading platform;

[0052] S2: Induction heating desoldering: The circuit board is moved to the induction heating station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the circuit board is desoldered by the induction heating source;

[0053] S3: Applying solder or flux: The desoldered circuit board is moved to the fluxing station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the fluxer reapplies solder and / or flux to the circuit board;

[0054] S4: Get new components or chips: while applying solder or flux, grab new components with corresponding functions;

[0055] S5: Die bonding: Based on the coordinate parameters of the circuit board and the part to be repaired, the new components are placed on the circuit board that has been re-applied with solder and / or flux. The circuit board is moved to the induction heating station and the circuit board is re-soldered by the induction heating source to complete the repair.

[0056] Furthermore, in this specific embodiment, S1 is specifically:

[0057] S11: Perform AOI inspection on the circuit board to obtain the ideal coordinate parameters of the circuit board and the parts that need to be repaired;

[0058] S12: Setting a loading platform with X-axis and Y-axis freedom, placing the circuit board to be repaired on the loading platform, and transmitting ideal coordinate parameters of the circuit board and the part to be repaired to the loading platform;

[0059] S13: The camera is dispatched to photograph the circuit board from above the loading platform, and the photographed circuit board image is analyzed to identify and locate the marking points on the circuit board. Based on the located marking points on the circuit board, the ideal coordinate parameters of the circuit board and the parts requiring repair are superimposed on the current processing process to obtain the actual coordinate parameters of the circuit board and the parts requiring repair during the current processing process.

[0060] Furthermore, in this specific embodiment, S2 is specifically:

[0061] S21: An induction heating source is provided which is fixed in the X-axis and Y-axis directions and has only a degree of freedom in the Z-axis direction, and the position where the induction heating is applied to the external workpiece is defined as the induction heating station;

[0062] S22: Based on the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform moves the circuit board to the induction heating station;

[0063] S23: Detect the substrate thickness of the current circuit board and the size and height data of the components at the location requiring rework;

[0064] S24: adjusting the height of the induction heating source along the Z-axis direction according to the current substrate thickness of the circuit board and the size and height of the components at the location to be repaired, and controlling the alternating magnetic field generated by the induction heating source to cover the location to be repaired, thereby melting the solder;

[0065] S25: Recycle and remove loose original components;

[0066] S26: Dispatching the induction heating source to continuously heat the pads on the circuit board and the residual tin layer on the pads to level the pads;

[0067] S27: After desoldering, the camera is dispatched to shoot the exposed pads from above the current circuit board.

[0068] Furthermore, in this specific implementation, S3 is specifically:

[0069] S31: setting a tinning head or a flux applying head with freedom in the X-axis direction and the Z-axis direction, and setting the real-time tin outlet of the tinning head or the real-time flux outlet of the flux applying head as the fluxing station;

[0070] S32: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform and the tinning head or flux application head move simultaneously to move the desoldering circuit board to the fluxing station, and allow the tinning head or flux application head to move downward along the Z-axis direction to re-apply solder or flux to the pads on the circuit board.

[0071] Furthermore, in this specific embodiment, S4 is specifically:

[0072] S41: New components that are fully functional and have the same function and model as the original components on the circuit board are stored in the categories of R, G, and B;

[0073] S42: While applying solder or flux, dispatch a camera to capture the classified and stored new components, locate each new R, G, B chip based on the captured image, obtain the specific coordinates of the specified new R, G, B chip required for the current rework, and select and capture the new R, G, B chip with the same functional model as the original R, G, B chip removed by desoldering;

[0074] S43: dispatching the camera to shoot the captured new R, G, B chips from below, analyzing the captured images of the new R, G, B chips, and identifying the posture of the captured new R, G, B chips;

[0075] S43: Compare the posture of the new R, G, and B chips currently being grasped with the actual coordinate parameters of the circuit board and the part requiring rework, and analyze whether the posture of the pads in the new R, G, and B chips currently being grasped is consistent with the posture of the original pads at the part requiring rework. If there is a deviation between the two, adjust the grasping posture until the two postures are consistent.

[0076] Furthermore, in this specific embodiment, S43 is specifically:

[0077] S431: Acquire the image of the exposed pad captured in step S27, and analyze the location of the pad at the location where desoldering has been completed on the current circuit board, the number of pads, the orientation of each pad, and the distribution of different pads on the circuit board;

[0078] S432: Acquire the image of the new R, G, and B chips captured in step S42, and analyze the pad distribution of the new R, G, and B chips captured from the image;

[0079] S433: Compare the setting orientation of a single pad in the pad at the position where desoldering has been completed in the current circuit board, the distribution of different pads on the circuit board with the pad distribution of the new R, G, B chip currently being grasped. If the two are consistent, jump to S5; if the two are inconsistent, reverse the grasping angle of the new R, G, B chip, and adjust the grasping posture of the new R, G, B chip until the two are consistent.

[0080] Furthermore, in this specific implementation, S5 is specifically:

[0081] S51: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform is controlled to move the circuit board closer to the new R, G, and B chips, and the new R, G, and B chips are placed on the circuit board that has been re-applied with solder and / or flux;

[0082] S52: moving the pads of the circuit board to which solder and / or flux have been reapplied to the induction heating station according to actual coordinate parameters of the circuit board and the part to be repaired;

[0083] S53: Allow the induction heating source to move downward along the Z-axis direction, and control the alternating magnetic field generated again at the induction heating source. The alternating magnetic field induction heats the pads, the metal pads of the new R, G, and B chips, and the re-applied solder, thereby soldering the new R, G, and B chips to the circuit board.

[0084] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A circuit board repair method using fixed-point induction heating, characterized in that: The method is: S1: Loading: Set up a loading platform with X-axis and Y-axis freedom, obtain the actual coordinate parameters of the circuit board and the part to be repaired, and place the circuit board to be repaired on the loading platform; S2: Induction heating desoldering: The circuit board is moved to the induction heating station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the circuit board is desoldered by the induction heating source; S3: Applying solder or flux: The desoldered circuit board is moved to the fluxing station according to the actual coordinate parameters of the circuit board and the part to be repaired, and the fluxer reapplies solder and / or flux to the circuit board; S4: Get new components or chips: while applying solder or flux, grab new components with corresponding functions; S5: Die bonding: According to the coordinate parameters of the circuit board and the part to be repaired, the new components are placed on the circuit board to which solder and / or flux are reapplied, and the circuit board is moved to the induction heating station. The circuit board is re-welded by the induction heating source to complete the repair; The S1 is specifically: S11: Perform AOI inspection on the circuit board to obtain the ideal coordinate parameters of the circuit board and the parts that need to be repaired; S12: Setting a loading platform with X-axis freedom and Y-axis freedom, placing the circuit board to be repaired on the loading platform, and transmitting the ideal coordinate parameters of the circuit board and the part to be repaired to the loading platform; S13: dispatching a camera to photograph the circuit board from above the loading platform, analyzing the photographed circuit board image, identifying and locating the marking points on the circuit board, and superimposing the ideal coordinate parameters of the circuit board and the part requiring repair into the current processing according to the located marking points on the circuit board, so as to obtain the actual coordinate parameters of the circuit board and the part requiring repair in the current processing; The S3 is specifically: S31: a tinning head or a flux applying head having a degree of freedom in the X-axis direction and a degree of freedom in the Z-axis direction is provided, and a real-time tin outlet of the tinning head or a real-time position of a flux outlet of the flux applying head is set as a soldering station; S32: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform and the tinning head or flux applying head move simultaneously, and the circuit board that has been desoldered is transferred to the fluxing station, and the tinning head or flux applying head is allowed to move downward along the Z-axis direction to re-apply solder or flux to the pad on the circuit board; The S4 is specifically: S41: Classify and store new components that have intact functions and correspond to the original components on the circuit board; S42: while applying solder or flux, selecting and grabbing a new component that has the same functional model as the original component removed by desoldering; S43: dispatching the camera to shoot the captured new component from below, analyzing the captured image of the new component, and identifying the posture of the currently captured new component; S43: Compare the posture of the new component currently grasped with the actual coordinate parameters of the circuit board and the part that needs to be repaired, and analyze whether the posture of the pad in the new component currently grasped is consistent with the original posture of the pad at the part that needs to be repaired. If there is a deviation between the two, adjust the grasping posture until the two postures are consistent.

2. The circuit board repair method using fixed-point induction heating as claimed in claim 1, characterized in that: The S2 is specifically: S21: An induction heating source is arranged to be fixed in the X-axis direction and the Y-axis direction and has only a degree of freedom in the Z-axis direction, and the position where the induction heating is performed on the external workpiece is defined as the induction heating station; S22: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform moves the circuit board to the induction heating station; S23: Detect the substrate thickness of the current circuit board, and the size and height data of the components at the location requiring repair; S24: adjusting the height of the induction heating source along the Z-axis direction according to the current substrate thickness of the circuit board and the size and height of the components at the part to be repaired, and controlling the alternating magnetic field generated at the induction heating source to cover the part to be repaired, thereby melting the solder; S25: Recycle and remove loose original components; S26: The induction heating source is arranged to continuously heat the pads on the circuit board and the residual tin layer on the pads to level the pads.

3. The circuit board repair method using fixed-point induction heating as claimed in claim 2, characterized in that: The S2 also includes S27: after desoldering, scheduling the camera to photograph the exposed solder pads from above the current circuit board.

4. The circuit board repair method using fixed-point induction heating as claimed in claim 3, characterized in that: The S43 is specifically: S431: Acquire the image of the exposed pad captured in step S27, and analyze the setting position, number of pads, setting orientation of a single pad, and distribution of different pads on the circuit board at the position where desoldering has been completed in the current circuit board; S432: Acquire the image of the new component captured in step S42, and analyze the pad distribution of the new component currently captured from the image; S433: Compare the setting orientation of a single pad in the pads at the position where the desoldering has been completed in the current circuit board, the distribution of different pads on the circuit board with the pad distribution of the new component currently being grabbed. If the two are consistent, jump to S5; if the two are inconsistent, reverse the grabbing angle of the new component and adjust the grabbing posture of the new component until the two are consistent.

5. The circuit board repair method using fixed-point induction heating as claimed in claim 4, characterized in that: The S5 is specifically: S51: According to the actual coordinate parameters of the circuit board and the part to be repaired, the loading platform is controlled to carry the circuit board to move closer to the new component, and the grabbed new component is placed on the circuit board to which the solder and / or flux is reapplied; S52: according to the actual coordinate parameters of the circuit board and the part to be repaired, the pads of the circuit board to which the solder and / or flux have been reapplied are moved to the induction heating station; S53: Allow the induction heating source to move downward along the Z-axis direction, control the alternating magnetic field generated again at the induction heating source, and use the alternating magnetic field to inductively heat the pad, the metal pad of the new component, and the re-applied solder to solder the new component to the circuit board.

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