KR102041277B1 - System for inspecting and modifying PCB soldering - Google Patents

Abstract

The present invention relates to a PCB soldering inspection and correction system, capable of significantly reducing defective products to reduce costs, which comprises: a conveyor (100); a vision tester (200) for detecting a soldering failure; an orthogonal robot (300) for gripping and moving a printed circuit board (20); a correction stand (400) for receiving the vertically reversed printed circuit board (20); and a correction robot (500) for correcting the soldering failure of the printed circuit board (20).

Description

System for inspecting and modifying PCB soldering}

The present invention relates to a soldering inspection and correction system for a PCB, and more particularly, to a soldering inspection and correction system for a PCB that can automatically correct the detected solder defects in addition to inspecting the solder failure of the PCB.

In general, a printed circuit board assembly (PCBA) for driving and controlling an electronic product is provided in an electronic product. The printed circuit board assembly is obtained by bonding various electronic components to a printed circuit board (PCB).

Specifically, in the state where the leads of the various electronic components are placed on the printed circuit board, the lead is melted on the leads of the electronic components to bond the electronic components to the printed circuit board. In the past, this process was performed manually by an operator. However, there is a problem that the defect rate is high and it is difficult to meet a certain amount and condition of lead suitable for each electronic component. Recently, a printed circuit board assembly is produced through a wave soldering process. have.

In the wave soldering process, the circuit board assembly (PCBA) is continuously circulated through the device to make contact with the surface of the flowing molten solder, and soldering is performed. However, soldering defects such as short lead, shorts, lead balls, and lead leads are still present.

If the printed circuit board assembly in which the soldering failure occurs is mounted on the electronic product, a malfunction occurs. The soldering state of each electronic component bonded on the printed circuit board is inspected before the printed circuit board assembly is mounted on the electronic product. shall.

As a method for inspecting the soldering state, an inspection may be performed by a worker by a human eye or by a soldering inspection system. In the case of the visual inspection by the operator, the quality of the product is not constant and the inspection time is long due to the condition and skill of the operator. As a result, the productivity is remarkably decreased. Recently, the inspection is performed using a soldering inspection system. .

An example of this is disclosed in Korean Patent Laid-Open Publication No. 10-2010-0120909 (hereinafter, referred to as 'quoting invention'). According to the present invention, a soldering state of an electronic component bonded to a printed circuit board is inspected using a plurality of image acquisition apparatuses, thereby reducing inspection time and increasing inspection accuracy.

However, when soldering defects are detected using the soldering inspection system, the printed circuit board assembly, which is soldering defects, is discarded or an operator manually corrects the soldering defects. Therefore, the production cost is increased and the electronic components are corrected by manual soldering defects. In each case, it is difficult to meet the proper and constant amount and condition of lead again, and it is more likely to cause solder failure, and it takes a lot of work time to take appropriate measures according to the type of solder failure.

1. Republic of Korea Patent Publication No. 10-2010-0120909 'Soldering inspection system'

The present invention is to solve the problems as described above can check the soldering defects of the PCB and can automatically correct the detected soldering defects according to the type bar can significantly reduce the defects and the cost is reduced and It is an object of the present invention to provide a soldering inspection and correction system for PCB, which can reduce the working time.

Soldering inspection and modification system for a PCB according to the present invention for achieving the above object is a conveyor for moving the printed circuit board in one direction so that the electronic components are soldered and the solder surface is located below, soldering of the printed circuit board placed on the conveyor. Vision inspection machine for detecting soldering defects by inspecting the surface with a camera, an orthogonal robot capable of holding and moving the printed circuit board, and inverting the printed circuit board up and down, and a crystal stand receiving the printed circuit board upside down from the orthogonal robot. And a correction robot for correcting a solder failure of the printed circuit board placed on the crystal stand, wherein the correction robot includes a solder to suck or melt the solder on the solder surface by applying heat, and a suction to suck the melted solder. And a solder feeder for automatically supplying solder, wherein the printed circuit board is provided by a vision inspector. Defective soldering is detected by dividing the type into one of the following types: excessive and insufficient amount of lead soldered and a type of soldering, a short generation soldered to connect to an adjacent lead, and a lead ball generation with small lead particles present on a printed circuit board. The printed circuit board, in which the solder defect is detected as the lead quantity, the shortage type and the short generation type, is delivered to the crystal by an orthogonal robot, and the solder is melted by the suction after melting the solder at the corresponding point by the correction robot. The spot is re-soldered with solder and iron supplied from the solder feeder, and then moved to the conveyor at the point before passing the vision inspection machine by the orthogonal robot, and transfers the printed circuit board with the solder ball detected with the lead ball generation type. More including brushing stand to remove lead ball through brushing operation, The printed circuit board napbol generation type of soldering defect has been detected can be moved by the conveyor around the point to pass through the vision tester by is transmitted as brushing by an orthogonal robot after napbol is removed, the orthogonal robot.

In addition, the type of solder failure that can be detected through the vision inspector includes a lead uninserted in a state in which the lead of the electronic component is not inserted into the printed circuit board, and receives and moves the printed circuit board on which the solder failure is detected. Further comprising a discharge conveyor, the printed circuit board in which the lead uninserted solder failure is detected may be moved to the discharge conveyor by an orthogonal robot.

In addition, when the soldering defect is corrected in the crystal stand and brushing stand and moved to the conveyor, the printed circuit board may be moved to the discharge conveyor when the soldering defect is detected again through the vision inspection machine.

The apparatus may further include a correction wait stand installed between the conveyor and the correction stand so that the printed circuit board on which the soldering failure is detected is transferred to the correction standby by the orthogonal robot. It may be delivered in sequential order.

In addition, the vision inspector 3D photographing the printed circuit board with a camera to form a measurement value for the solder height, solder width and solder curvature at each soldering point on the soldering surface, and in advance to the appropriate soldering conditions according to the electronic component and soldering point By comparing the measured value and the set value set in the solder failure can be detected for each type.

In addition, an automatic soldering machine for soldering electronic components to the printed circuit board; And a cooling passage formed between the automatic soldering machine and the conveyor to be inclined downward toward the conveyor and having a cooling fan cooling the printed circuit board.

According to the present invention, the solder failure of the printed circuit board is detected by dividing the type into the lead quantity and shortage, short, lead ball, lead lead lead, and automatically performs appropriate correction and post-treatment according to the type of solder failure, bar defects significantly This reduces the cost and improves productivity by reducing the time required to correct poor soldering.

1 is a plan view showing the structure of a soldering inspection and correction system for a PCB according to the present invention,
Figure 2 is a view showing the structure of a printed circuit board assembly applied to the solder inspection and correction system for a PCB according to the present invention.

In the present invention, it is possible to automatically check the soldering defects of the PCB and to automatically detect the detected soldering defects according to the type of bar, which can greatly reduce the defective products, thereby reducing the cost and reducing the work time due to the soldering defect correction. A conveyor for moving the printed circuit board which is soldered and the soldering surface is located below; Vision inspection machine for detecting the solder failure by inspecting the soldering surface of the printed circuit board placed on the conveyor with a camera; An orthogonal robot capable of holding and moving the printed circuit board and inverting the printed circuit board up and down; A crystal receiving table receiving a printed circuit board inverted up and down from the orthogonal robot; And a correction robot for correcting a solder failure of a printed circuit board placed on the crystal stand, wherein the correction robot is a soldering iron that melts solder or melts solder on a soldering surface by applying heat, and a suction device for sucking molten solder. And a solder feeder for automatically supplying solder, while the printed circuit board is divided into types of lead and short lead that are soldered excessively or insufficiently by a vision inspector, and a short soldered to be connected to adjacent leads. Soldering failure is detected, the printed circuit board is detected by the orthogonal robot as a correction, and the soldering of the soldering point of the point by the correction robot with a soldering iron to remove the molten solder with a suction and then from the solder feeder The solder is soldered and soldered to the spot and then passed through a vision inspector by the orthogonal robot. That move the conveyor around the soldering point is proposed for PCB testing and modifying system as claimed.

The scope of the present invention is not limited to the embodiments described below, and may be variously modified and implemented by those skilled in the art without departing from the technical gist of the present invention.

Hereinafter, the soldering inspection and modification system for the present invention will be described in detail with reference to the accompanying Figures 1 and 2.

Soldering inspection and modification system for the present invention, the PCB includes a conveyor 100, a vision inspection machine 200, orthogonal robot 300, crystal platform 400 and crystal robot 500, brushing The stage 600, the discharge conveyor 700, the crystal standby stage 800, the automatic soldering machine 910, may further include a cooling passage 920.

First, the conveyor 100 moves the printed circuit board 20 in one direction so that the electronic component 10 is soldered and the soldering surface is positioned below. Here, the electronic component 10 means a resistor, a capacitor, an inductor, a connector, a switched mode power supply (SMPS), etc. The electronic components 10 all penetrate through holes formed at a mounting point on the printed circuit board 20. Leads are formed, and solder is performed on the leads that penetrate the printed circuit board 20. By the soldering, the electronic component 10 is fixed on the printed circuit board 20, and the opposite side to the surface on which the electronic component 10 is located, that is, the surface on which the solder is made, is called a soldering surface.

The conveyor 100 moves the printed circuit board 20 in one direction in a state where the printed circuit board 20 is placed so that the soldering surface is located below to prevent damage to the electronic component 10. Pass it through. Therefore, the conveyor 100 forms a long state in both directions with respect to the vision inspector 200. That is, the conveyor 100 continuously moves the printed circuit board 20 passing through the vision inspector 200 in one direction, and passing through the vision inspector 200 is irrelevant to whether there is a solder failure.

In addition, each printed circuit board 20 may include a unique code such as a barcode, QR code, etc. containing product information, such as a serial number, the unique on the conveyor 100 before passing through the vision inspection machine 200 A first scanner 110 capable of recognizing a code may be provided.

Meanwhile, the present invention may further include an automatic soldering machine 910 for soldering the electronic component 10 to the printed circuit board 20 to be placed on the conveyor 100. In the automatic soldering machine 910, the conveyor 100 may directly receive the printed circuit board 20 on which the electronic component 10 is soldered, but a cooling passage installed between the automatic soldering machine 910 and the conveyor 100 ( 920 can be configured to go through.

For example, the cooling passage 920 is formed to be inclined downward toward the conveyor 100, so that the printed circuit board 20 passing through the automatic soldering machine 910 may naturally move to the conveyor 100, and a cooling fan. It is provided to cool the printed circuit board 20. The cooling fan may be provided at at least one of the upper side, the lower side, and the side of the cooling passage 920 to cause the solder to be firmly fixed by generating a wind toward the printed circuit board 20. In addition, the cooling passage 920 may also serve to control the movement of the printed circuit board 20 to the conveyor 100.

The vision inspector 200 detects a solder failure by inspecting the solder surface of the printed circuit board 20 placed on the conveyor 100 with a camera. In this case, the soldering failure may include excessive or insufficient lead amount of the solder lead, a short lead soldered to be connected to an adjacent lead, a lead ball having small lead particles on the printed circuit board 20, and the electronic component 10. The lid includes a lead uninserted in a state where the lead is not inserted into the printed circuit board 20.

For example, the conveyor 100 may be configured to support only the both edges of the printed circuit board 20 while exposing the remaining portions except the both edges of the printed circuit board 20 to the outside. In this case, the camera of the vision inspector 200 may be provided below or / and side of the printed circuit board 20 to photograph the printed circuit board 20. In addition, between the camera and the printed circuit board 20 is provided with a recording plate made of a material which is transparent and strong enough to prevent the refraction does not occur during the shooting of the camera without scratches, to prevent foreign substances from falling into the camera. Can be.

Since the foreign matter may fall from the printed circuit board 20 or the outside of the photographing plate, the vision inspector 200 may further include a foreign matter removing fan that causes wind toward the photographing plate every predetermined time, or photographing every predetermined time. A foreign substance removal brush may be further provided to shake off the foreign substance of the plate.

In addition, the camera may be a camera capable of shooting 2D, but it is preferable that the camera is a 3D depth camera (3D Depth camera) that can shoot 3D to confirm the correct soldering failure. Therefore, the vision inspector 200 3D photographs the printed circuit board 20 with a camera, and the solder height H, the solder width D, and the solder curvature for each soldering point on the solder surface as shown in FIG. 2. Measured values can be formed. By using the solder height (H) and the solder width (D) may be further formed to measure the measurement of how much the solder is formed at an angle with respect to the printed circuit board (20).

The vision inspector 200 is set in advance to determine the appropriate soldering conditions, that is, the proper solder height, the proper solder width, and the proper solder curvature, depending on the soldering points of the electronic component 10 and the printed circuit board 20. Has a value. For example, a coordinate value may be assigned to each of the points where soldering is to be performed in the printed circuit board 20, and the appropriate soldering condition as described above may be formed as a set value for each coordinate. Therefore, the vision inspector 200 may detect solder failure by type by comparing the set value with the measured value.

In addition, the vision inspector 200 may detect solder failure by type, and may perform an accuracy and repeatability of solder failure detection at a high processing speed using an artificial neural network. The vision inspector 200 may store test results such as the number of printed circuit boards 20 without solder defects and the number of printed circuit boards 20 in which solder defects exist, and the printed circuit boards with solder defects may exist. For (20), the coordinate values, the types of the soldering defects, and the like at the point where the soldering failure occurs can be coded and stored.

The orthogonal robot 300 may hold and move the printed circuit board 20 and reverse the printed circuit board 20 up and down. That is, the orthogonal robot 300 moves the printed circuit board 20 from the conveyor 100 to any one of the crystal stand 400, the brushing stand 600, the discharge conveyor 700, the crystal wait stand 800. The printed circuit board 20 may be moved to the conveyor 100 at any one of the crystal stand 400 and the brushing stand 600. For example, the orthogonal robot 300 is formed in the shape of a bar (bar) having a predetermined length is provided on the upper side of the conveyor 100 and the moving table 310 is moved along the longitudinal direction of the conveyor 100, and It may include a gripper 320 which is moved along the longitudinal direction of the mobile unit 310 and can hold the printed circuit board 20 substantially and upside down.

The crystal stand 400 receives the printed circuit board 20 inverted up and down from the orthogonal robot 300, wherein the printed circuit board 20 is placed on the upper surface of the crystal stand 400 so that the soldered surface faces upward. . This is because the printed circuit board 20 on the conveyor 100 or the crystal standby stand 800 to be described later, the soldering surface is directed downward, the printed circuit board 20 by the orthogonal robot 300 for easy correction of the soldering failure. ) To move up and down the crystal stage 500.

Between the conveyor 100 and the crystal stand 400, a crystal wait stand 800 on which the printed circuit board 20 in which solder failure is detected may be further provided. The crystal waiting stand 800 may be formed in a plate shape having a predetermined length, and may also be formed in a form in which the printed circuit board 20 may be moved, such as the conveyor 100. In addition, in terms of utilization of the space, the crystal wait 800 is preferably arranged in parallel with the conveyor (100).

When the printed circuit board 20 is placed on the crystal stand 400, the crystal wait stand 800 is a space where the printed circuit board 20, in which solder failure is detected, can be waited before being moved to the crystal stand 400. Can be provided. Alternatively, before the printed circuit board 20 is placed on the crystal stand 400, the printed circuit board 20 may be moved to the crystal stand 400 after passing through the crystal wait stand 800. That is, the printed circuit board 20 in which the soldering failure is detected may be delivered to the crystal wait stand 800 by the orthogonal robot 300, and then sequentially transferred to the crystal stand 400.

In addition, the correction wait 800 may be provided with a second scanner 810 that can recognize the unique code, such as the first scanner 110. The printed circuit board 20 in which the soldering defect is detected may be given correction information such as the sequence, the soldering defect type, and the like in the vision inspector 200 before being moved to the crystal waiting stand 800, and the second scanner 810. Recognizes the unique code of the printed circuit board 20 located in the correction standby (800) to determine whether the corrected printed circuit board 20 is correct, the printed circuit board 20 is given the correction information If correct, the correction information may be transmitted to the correction robot 500.

On the other hand, the correction robot 500 corrects the soldering failure of the printed circuit board 20 placed on the crystal table (400). To this end, the crystal robot 500 is provided with a soldering machine for automatically supplying solder and a soldering iron for melting or dissolving solder on a soldering surface by applying heat, a soldering machine for sucking molten solder, and a solder. In addition, the brushing stand 600 may receive the printed circuit board 20 and brush the brushing work, that is, brushing off using a brush. The discharge conveyor 700 prints the solder defect detected from the conveyor 100. The circuit board 20 is received and moved to be discarded or further processed.

According to the present invention, the soldering defect is corrected by the correction robot 500 by moving the printed circuit board 20 from the conveyor 100 to the crystal table 400 according to the type of soldering defect, The soldering defect may be corrected by moving to 600, and may be moved from the conveyor 100 to the discharge conveyor 700 to be disposed of or further processed.

Specifically, the printed circuit board 20 in which the soldering shortage or short soldering failure is detected is orthogonal robot 300 through the crystal table 400 (or crystal waiting table 800) on the conveyor 100 by the orthogonal robot 300 ( 400)), the soldering point of the point is melted by the crystal robot 500 with a soldering iron, the molten solder is removed with a suction device, and the solder and the solder supplied from the solder feeder are re-solded with the soldering point. As such, the printed circuit board 20 in which the soldering defect is corrected is moved to the conveyor 100 at the point before passing the vision inspector 200 by the orthogonal robot 300.

In addition, the printed circuit board 20 in which lead solder is detected to be soldered is transferred to the brushing stand 600 by the orthogonal robot 300, and after the lead balls are removed through the brushing operation, the vision inspector is operated by the orthogonal robot 300. It is moved to the conveyor 100 at the point before passing through the 200.

Accordingly, the soldering defect is corrected in the fixation stand 400 and the brushing stand 600, and the printed circuit board 20 moved to the conveyor 100 is inspected again by the vision inspector 200 to check whether there is a solder failure. If the soldering failure is detected again, it can be moved to the discharge conveyor 700 by the orthogonal robot 300.

Then, the printed circuit board 20, in which the lead uninserted solder defect is detected, cannot be corrected in the crystal stand 400 or the brush stand 600, and is moved to the discharge conveyor 700 by the orthogonal robot 300.

As described above, the soldering inspection and correction system for the present invention detects the solder failure of the printed circuit board 20 by dividing it into types of lead quantity and shortage, short, lead ball, and lead lead, and automatically corrects them automatically according to the type of solder failure. And after the post-treatment, it is possible to significantly reduce the defective products can reduce the cost and shorten the work time due to the correction of the solder failure can improve the productivity.

10: electronic component 20: printed circuit board
100: conveyor 110: first scanner
200: vision inspector 300: orthogonal robot
310: mobile unit 320: gripper
400: Crystal Tower 500: Crystal Robot
600: brushing table 700: discharge conveyor
800: waiting for modification 810: second scanner
910: automatic soldering machine 920: cooling passage

Claims (6)

A conveyor (100) for moving the printed circuit board (20) in one direction, in which the electronic component (10) is soldered and the solder surface is located below;
Vision inspection machine 200 for detecting a solder failure by inspecting the solder surface of the printed circuit board 20 placed on the conveyor 100 with a camera;
An orthogonal robot 300 capable of holding and moving the printed circuit board 20 and inverting the printed circuit board 20 up and down;
A crystal table 400 receiving the printed circuit board 20 inverted up and down from the orthogonal robot 300;
Correcting robot 500 for correcting the soldering failure of the printed circuit board 20 placed on the crystal table 400;
An automatic soldering machine 910 for soldering the electronic component 10 to the printed circuit board 20; And
It includes a cooling passage 920 formed between the automatic soldering machine 910 and the conveyor 100 to be inclined downward toward the conveyor 100 and provided with a cooling fan for cooling the printed circuit board 20.
The crystal robot 500 is provided with a soldering iron for melting or soldering the solder on the solder surface by applying heat, a suction for sucking the molten solder, and a solder feeder for automatically supplying the solder,
The printed circuit board 20 has a lead amount and an insufficient amount of lead that is soldered excessively or insufficiently by the vision inspector 200, a short generation type that is soldered to be connected to an adjacent lead, and a small lead on the printed circuit board 20. Lead ball generation type in which particles exist, dividing the type into one of the types, the failure of soldering is detected,
The printed circuit board 20 in which the soldering defect is detected as the lead quantity and shortage type and the short generation type is transmitted to the crystal table 400 by the orthogonal robot 300, and the soldering at the corresponding point by the correction robot 500. After melting with a soldering iron to remove the molten solder with a suction and the solder and the soldering point supplied by the soldering point is re-soldered, and then passed through the vision inspection machine 200 by the orthogonal robot (300) 100),
Further comprising a brush (600) for receiving the printed circuit board 20, the solder ball is detected as the lead ball generation type to remove the lead ball through the brushing operation,
The printed circuit board 20 in which the solder ball generation type solder defect is detected is transferred to the brushing stand 600 by the orthogonal robot 300 and the lead balls are removed, and then the vision inspection machine 200 is performed by the orthogonal robot 300. Move to the conveyor 100 at the point before passing),
The type of solder failure that can be detected through the vision inspector 200 includes a lead uninserted in which a lead of the electronic component 10 is not inserted into the printed circuit board 20.
Further comprising a discharge conveyor 700 for receiving and moving the printed circuit board 20 detected the solder failure,
The printed circuit board 20 in which the lead uninserted solder defect is detected is moved to the discharge conveyor 700 by the orthogonal robot 300,
When the soldering defect is corrected in the crystal stand 400 and the brushing stand 600 and moved to the conveyor 100, the printed circuit board 20 is again detected through the vision inspection machine 200. Is moved to the discharge conveyor 700,
Further comprising a crystal waiting 800 is installed between the conveyor 100 and the crystal table 400 is placed on the printed circuit board 20, the solder failure is detected,
The printed circuit board 20 in which the soldering failure is detected is transferred to the crystal standby stage 800 by the orthogonal robot 300, and then sequentially transferred to the crystal substrate 400.
The vision inspector 200 3D photographs the printed circuit board 20 with a camera to form measured values for solder height H, solder width D, and solder curvature at each soldering point having coordinate values on the solder surface. In addition, according to the soldering point having the electronic component 10 and the coordinate value, the soldering failure is detected for each type by comparing the measured value and the preset value set in advance with the proper soldering conditions.
Further comprising a first scanner 110 that can recognize the unique code provided on each printed circuit board 20 on the conveyor 100 before passing through the vision inspection machine 200,
The unique code includes at least one of a barcode and a QR code containing product information, including a serial number,
The vision inspector 200,
At least one of a debris removal fan that causes wind toward the photographing plate every predetermined time and a debris removing brush that can shake off the foreign matter of the photographing plate every predetermined time are provided.
The vision inspector 200,
Test results including the number of printed circuit boards 20 without soldering defects and the number of printed circuit boards 20 with soldering defects are stored as data, and soldering defects are applied to the printed circuit board 20 with soldering defects. Code and store the coordinates of the point where it occurred and the type of soldering failure,
The printed circuit board 20 in which the soldering defect is detected is given correction information including the sequence and the type of soldering defect in the vision inspector 200 before being moved to the crystal waiting stand 800.
The correction wait 800 is
A second scanner 810 is provided that can recognize the unique code,
The second scanner 810 recognizes the unique code of the printed circuit board 20 located in the correction standby (800) to check whether the corrected printed circuit board 20 is correct, and the correction Soldering inspection and modification system for a PCB, characterized in that for transmitting the corrected information to the printed circuit board 20 is given to the correction robot 500. delete delete delete delete delete

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