KR100607822B1 - Apparatus for determining the position of pcb processing drill and determining design parameter of the pcb - Google Patents

Abstract

The present invention discloses an apparatus for determining the position and PCB design value of a drill for PCB processing.

According to the present invention, a control apparatus for determining a position of a drill in a PCB including a circular hole serving as a position reference of a drilling operation, comprising: an image photographing unit for photographing an image including a hole, a position and a drill The hole information determination unit for obtaining the size and position of the hole to be formed in the PCB by the drill from the diameter of the bit mounted on the hole and the position and size of the hole captured by the image pickup unit, the position of the hole obtained by the hole information determination unit, and Comparing the size to adjust the position of the drill so that the center of the hole to be formed by the drill coincides with the center of the hole, and includes a position control unit for determining the adjusted position as the reference position of the drill, saving time in PCB manufacturing This can improve productivity and reduce defective parts, resulting in lower production costs, resulting in greater efficiency in all industries using PCB.

Description

Apparatus for determining the position of PCB processing drill and determining design parameter of the PCB}

1 is a block diagram showing the configuration of an apparatus for determining a position and PCB design value of a drill for PCB processing according to the present invention.

2 illustrates a specific example of the apparatus of FIG. 1.

3 shows an example of how a program providing an interface and a control function according to the present invention is displayed on a screen.

4 is an example of a work program according to the present invention.

5 highlights the positions of the holes and drills.

The present invention relates to the control of the position of the object, and relates to an apparatus for determining the position and PCB design value of the drill for PCB processing during PCB manufacturing.

The general manufacturing process of PCB used in electronic circuit is as follows.

After designing the circuit using CAD / CAM, the layout and wiring pattern to place the circuit on the PCB, a film with component layout and wiring for each layer of the PCB is produced. Then, in order to manufacture the PCB, each layer is laminated and drilled into the hole corresponding to the hole using a CNC machine. After that, they are shipped after inspection through electroless copper plating, laminating, exposure, development, electro copper plating, film peeling, corrosion, porter solder printing, silk printing, HA laminator, BBT, router, terminal gold plating, and V-CUT process.

At this time, the lamination process involves stacking MLB (Multi layer board) by stacking the inner layer substrate on which the circuit is made, the prepreg which is a resin for insulation, and the copper foil to be processed into the outer layer in order to maintain matching according to the design specifications. ) Process. If the matching is misaligned at the time of lamination, a problem arises in that the connection between layers is not made or adjacent wirings are shorted to each other. Therefore, inspection using X-Ray is necessary to check that the inner layers are correctly matched after lamination.

The drilling operation is to drill holes for inserting parts and holes for wiring between layers on the completed lamination process, and the drilling operation is performed by a drill of a CNC machine. Depending on the application, holes of various diameters must be machined, so bits of various drill bits are used. Drilling is the most time-consuming process in the PCB manufacturing process.

When drilling, data about the first substrate is input, and then a compensation hole for drilling the position of the drill is processed before drilling through the internal pattern. After machining the hole, the difference between the land of the inner layer and the position where the actual bit penetrates is inspected by X-ray, and the correction value is given to the drill of the CNC machine, and the drill operation is performed according to the corrected value.

As such, inspection using X-rays is essential when manufacturing a PCB, but the following problems exist in the conventional X-ray inspection method.

The conventional X-ray inspection method is an inspection method that relies on the judgment of the operator about the degree of internal pattern distortion in the lamination process or the degree of hole eccentricity in the drill process.

For example, during the x-ray inspection in the lamination process, the operator determines whether the printed circuit board is transparent or stretched or shrunk due to the senses, without any additional measuring tools. Work to correct non-value. As a result, different operators enter different conditions for the same defective substrate and work according to the input conditions.

Similarly, in the drill process, after the hole is corrected by the operator, only the operator's sense of how far the bit is from the center of the land, the result of the work is not uniform. As a result of the correction of the substrate processing based on the operator's sense, if the absence or turnover of an experienced worker occurs, the defective rate increases enormously, and even the skilled worker has a correction value according to the condition of the body of the day. To cause a failure.

In practice, the value to be corrected must be precise in units of μm, and it is impossible to calculate an accurate correction value of such a unit by the operator's sense alone.

In addition, since the PCB manufacturing process is almost finished, it is almost time to find out whether the PCB substrate has been worked properly. Therefore, when all the defects have been identified, almost all the processes have already passed. You will be wasting your time and financial losses.

As mentioned above, in order to perform accurate inspection of PCB products, it is possible to proceed with the manufacturing process up to the post process. In post-processing, the copper foil already laminated to the PCB needs to be stripped off and measured with a micro vision device, resulting in significant loss of time and money.

To compensate for this, X-ray inspection is used to see the inside of the PCB, but there is a disadvantage in that accurate measurement is not possible. have.

The technical problem to be achieved by the present invention, to solve the above problems, to provide a device for determining the position and PCB design value of the drill for PCB processing.

According to the present invention for solving the above technical problem, the device for determining the position and PCB design value of the drill for PCB processing, by determining the position of the drill with respect to the PCB including a circular hole that is the position reference of the drill operation An apparatus for inspecting a PCB, the apparatus comprising: an image capturing unit configured to photograph an image including the hole; A hole information determination unit for obtaining a size and a position of a hole to be formed in the PCB by the drill from the position of the drill and the diameter of a bit mounted to the drill; And adjusting the position of the drill so that the center of the hole to be formed by the drill coincides with the center of the hole by comparing the position and size of the hole captured by the image capturing unit with the position and size of the hole obtained by the hole information determining unit. It is characterized in that it comprises a; position control unit for determining a predetermined position as a reference position of the drill.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing the configuration of an apparatus for determining a position and PCB design value of a drill for PCB processing according to the present invention.

The control device for determining the position of the drill 110 with respect to the PCB 100 including a circular hole as a reference of the position of the drill operation, the image pickup unit 120 for capturing an image including the hole, The hole information determination unit 130 and the image capturing unit 120 which obtain the size and the position of the hole to be formed in the PCB 100 by the drill 110 from the position of the drill 110 and the diameter of the bit mounted on the drill are captured by the image. The position and size of one hole is compared with the position and size of the hole determined by the hole information determination unit 130, and the position of the drill is adjusted so that the center of the hole to be formed by the drill 110 coincides with the center of the hole. It includes a position control unit 140 to determine the position as the reference position of the drill.

The image capturing unit 120 captures an image using X-rays. Various methods can be used for the imaging using the X-ray, for example, a device such as a portable X-ray projection apparatus of registration number 10-0264901 described in the Republic of Korea registration publication can be used.

In order to obtain the best image result, averaging is performed to remove noise of the image using X-ray, and image correction value (LUT; lookup table correction) is set to adjust contrast.

The captured image has a circular hole, and obtaining a center of the original image obtained through a computer can be easily performed by those skilled in the art to which the present invention pertains through various methods.

And the position controller 140 adjusts the position of the drill independently or two axes are moved for each axis of the X axis and Y axis when the surface of the PCB to the X-Y coordinate plane. Alternatively, you can change the position of the PCB by fixing the position of the drill and adjusting the position of the stage on which the PCB is placed. At this time, the two X, Y axes can be moved independently or simultaneously to change the position.

If it is necessary to adjust the magnification of the image captured by the image capturing unit 120, a zoom lens mounted on the camera may be used, but the image capturing unit 120 moves in a direction perpendicular to the surface of the PCB to increase the magnification of the image. I can regulate it.

2 illustrates a specific example of the apparatus of FIG. 1.

The device controlled by the computer 200 is largely comprised of an image acquisition and processing portion 210, a motion control portion 220 including a motor and a linear encoder, an X-ray control portion 230 controlling an X-ray device, and various on / off operations. It is divided into an I / O interface expansion board part 240 for off operation and detection.

The camera 215 uses a black and white camera due to its X-ray characteristic, and a high resolution digital camera using a resolution of 1024x768 pixels or more. In order to observe the speed and the high resolution, the image acquisition and processing board 210 is shown in real time so as to have the same resolution without enlarging or reducing the captured image.

The motion control board provides the ability to move the position via a computer.

Two motors 222 for the movement and control of the XY axis of the stage or the drill on which the PCB is placed, two linear encoders 226 for sensing each position, and a motor for controlling the magnification by moving the stage itself up and down One 224 and one linear encoder 228 for position sensing. Each motor and linear encoder operate in pairs, and two limit switches are connected to both ends of each stage and the motor drive shaft to prevent the stage from breaking out, forcibly stopping the motor.

In addition to the limit switch at the end of each stage, the I / O interface board 240 for receiving the On / Off state of various switches is communicated with the computer 200 via a serial interface.

The X-ray generator 235 monitors the state of the X-ray and communicates with the X-ray controller 230 to control the on / off, output voltage and current. All states are shown in the computer 230 in the same state as the controller, and only the controller can operate itself when switching to manual mode.

Compared with the configuration of FIG. 1, the image capturing unit 120 includes a camera, an image acquisition and processing board 210, a computer 200, an X-ray controller 230, and an X-ray generator 235. The hole information determination unit 130 is implemented through a predetermined program embedded in the computer 200, and the position control unit 130 includes a predetermined program embedded in the computer 200, a motion control board 220, and a driving motor ( 222, 224 and linear encoders 226, 228.

The position of the drill to match the center of the hole and the center of the drill, and information about the bits mounted on the drill are notified to the program according to the present invention included in the computer 200 through the motion control board. And the center of the drill can be matched.

3 shows an example of how a program providing an interface and a control function according to the present invention is displayed on a screen.

The program for carrying out the present invention may consist of three programs that can actually be operated individually. Setting / measurement program to select and measure the measurement elements to configure and define the actual measurement behavior, and work program for secondary processing of the operator's convenience and measurement results to suit the eccentric measurement task according to the present invention, and reporting convenience of engineers and operators And a reporting program for supporting statistical work processing on the entire result. The job program supports the function of the position controller 140.

3 is an example of a setting / measurement program, and FIG. 4 is an example of a work program.

In FIG. 3, when the measurement elements are selected using the command menu 300 and each measurement element is disposed on the actual screen, the measurement elements are registered in the work list 310. The detailed part of the job is displayed in the command detail setting area 320, and the user may perform detailed setting, for example, inputting a design position. At the same time, the measurement element is operated and displayed on the current screen, and the result is displayed on the result display area 330. In addition, the entire command list is displayed in the command map area 340. The current position of the stage is displayed in real time in the stage position portion 350 at the top.

Examples of measurement elements or processing objects of the command menu 300 are as follows.

Dimensional elements: Allows you to select basic measurement elements. As the most basic measuring factor. Each measurement element alone produces a result.

Combination measurement elements: Secondary measurement elements that can be combined using the results of the preceding basic measurement elements. For example, if you select the previous line length measurement and select the two basic measurement elements above, the length is calculated automatically.

Coordinate setting element: It is an element to set the coordinate, and it can set origin, X axis and Y axis. The result of each measurement being placed on top of each other is reflected from the end of the input sequence. In other words, if you set the X axis and set the X axis, the Y axis is automatically set, but if you use the Y axis setting again, the axis is set using only the last X and Y axis settings.

Operation control element: It is used for equipment control operation such as power on / off operation of X-ray and operation sequence control related to execution of other commands.

Typical PCBs are rectangular. Hereinafter, a process according to the present invention will be described assuming a rectangular PCB.

It may be more effective to adjust the drill and hole eccentricity based on multiple holes. To this end, the present invention also uses a PCB center hole, a Y-axis setting hole located at the top of the hole, and a method using a plurality of holes located at the corners of the PCB.

The center hole is located right in the center of the PCB. This center hole is used as the origin when the PCB plane is referred to as the X-Y plane. And the Y-axis setting hole to set the reference for the Y-axis is located at 12 o'clock with respect to the center hole, and of course, is located on the PCB surface.

There are four test holes, one in each of the four corners of the PCB, located at the same coordinates relative to each other about the center hole, the origin.

5 highlights the positions of the holes and drills. 5a, 6a, 7a and 8a are test holes and 5b, 6b, 7b and 8b are holes to be formed by operation of a bite mounted on a drill. The hole created by the drill is smaller than the size of the test hole. When the actual PCB is manufactured, if the size of the hole due to the bite of the drill is larger than the hole according to the PCB's design guidelines, the circuit passing nearby can be damaged.

The present invention aims to bring the centers of these two circles into agreement. In FIG. 5, it can be seen that each test hole and the drill correspond to each other.

The image capturing unit 120 captures an image of the holes as described above, and the position controller 140 determines the coordinates of the PCB surface in the X-Y plane with the center of the center hole as the origin. When a difference between the straight line generated after the origin and the center of the Y-axis setting hole and the Y-axis of the X-Y plane occurs, the coordinates are generated again by constructing the X-Y plane based on the previously generated Y-axis. As described above, if the axes are inconsistent with each other, the coordinates are set again based on the later generated axes.

Therefore, the center of the drill and the test hole are matched based on the coordinates thus formed.

To this end, the hole information determination unit 130 obtains the size and position of the holes to be formed in the PCB by the drills from the positions of the drills and the diameters of the bits mounted in each drill. As described above, this can be obtained through the motion control board 220 of FIG. 2. Based on such information, the position controller 140 compares the position and size of the hole captured by the image capturing unit 120 with the position and size of the hole obtained by the hole information determination unit 130 to determine the holes to be formed by the drill. The positions of the drills are adjusted so that their centers coincide with the centers of the holes captured by the image capturing units 120, respectively, and the adjusted positions are determined as reference positions of the drills.

This will be described in more detail.

Since the test holes are located at each corner of the PCB relative to each other, i.e., overlapping with respect to the axis, connecting the centers of the test holes to each other also forms a rectangle. The center of gravity or center of gravity is calculated based on the centers of these test holes. This can be obtained by using the position of each hole and the coordinate of the PCB plane. The axis of the X and Y coordinates is determined based on the midpoint. The results would ideally be identical to the midpoint of the center hole and the X, Y coordinates based on that midpoint. The center of the test hole is called the first origin for the purpose of classification.

Similarly to the hole to be formed by the bite of the drill, the center point of the centers of the hole is obtained in the same manner as described above, and is called the second origin. Then, the X-Y coordinate axis based on the second origin is determined. Coordinate axes can be determined parallel to the corresponding origin and each side of the PCB. Likewise, the results would ideally be identical to the midpoint of the center hole and the X and Y coordinates based on that midpoint.

If the center of the test hole coincides with the center of the hole to be drilled, no additional calibration is required. However, in cases where there is a movement requirement for not only parallel movement but also for others, it may be difficult to correct the eccentricity by comparing between the centers. Thus, the relationship between the first origin point and the second origin point and coordinate axes according to the origin points is introduced.

If the first origin point and the second origin point are the same and overlap the same between the coordinate axes, check that the center of the hole due to the drill coincides with the test hole. In this case, no additional correction is necessary. However, in this case, if the center of the hole caused by the drill does not coincide with the test hole, it can be judged that the size of the PCB has changed. In this case, the size of the film used to produce the PCB can be determined to have changed in its entirety, and the action can be taken to make up for it. If a problem occurs like this, an error is displayed to inform it. If this error occurs, you may need to restart PCB fabrication to resize the film. That is, the present invention may provide not only PCB inspection but also a function required for PCB fabrication.

As described above, when the center of the hole due to the drill does not coincide with the test hole and the size of the PCB changes as a whole, the distance between the centers of the test holes or the polygon composed of the centers is caused by the drill corresponding to each test hole. Compared to the polygon consisting of the center of the hole, it is possible to create a criterion that the spacing between test holes should be increased or decreased. To reflect this, new films used in PCB fabrication will have to be created. Through such a procedure, the present invention may eventually determine the design values of the patterns inside the PCB.

If the centers do not overlap and the intervals between the axes are constant, this means that the registration is not properly performed. In this case, the desired result may be obtained by moving the drill in parallel according to the distance difference from the center.

If the centers are overlapped but the spacing between the axes is not constant, this means that the angle between the axes is constant so that the desired result can be obtained by rotating in the opposite direction of the angle between the axes with respect to the overlapping centers.

Depending on the position between the centers and the axis, in some cases it may be necessary to perform both rotational and parallel movements.

For the movement as described above, the position control unit 140 controls each of the drills to be able to move independently of the other drills. Each drill must be provided with means such as a motor to move in the X and Y axes, respectively. There is also a need for means for rotational movement. Adopting such means in the present invention is easily adopted by those skilled in the art to which the present invention pertains, and thus a detailed description thereof will be omitted.

Instead of doing the calibration work as described above and doing the calibration work for each PCB individually, the instructions and sequence of instructions when the calibration work is executed or when executed through the above-mentioned program are stored. If the PCB is mounted on the stage of the device according to the present invention to retrieve and execute the stored instructions and order is automatically checked for the PCB. This allows for efficient automatic PCB verification. Whenever work is done on each PCB, you can report on the results so you can easily report on good and bad parts.

In addition, according to the present invention, if the stage equipped with the PCB is moved, the hole is confirmed, but if the drill is mounted and used in the machining, it may be used directly in the PCB machining, so it may be used not only after the operation but also in the actual machining work. Can be provided.

Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. Examples included in the above description are introduced for the understanding of the present invention, and these examples do not limit the spirit and scope of the present invention. It will be apparent to those skilled in the art that various embodiments in accordance with the present invention in addition to the above examples are possible. The scope of the present invention is shown not in the above description but in the claims, and all differences within the scope will be construed as being included in the present invention.

In addition, it can be easily understood by those skilled in the art that each of the above steps according to the present invention can be variously implemented in software or hardware using a general programming technique.

And some steps of the invention may also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, CD-RW, magnetic tape, floppy disks, HDDs, optical disks, magneto-optical storage devices, and carrier wave (eg, Internet It also includes the implementation in the form of). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

According to the present invention, in the apparatus for determining the position of the drill for PCB processing and the PCB design value for a PCB including a circular hole as a reference of the position of the drill operation, the image pickup unit for imaging an image including the hole, The hole information determination unit and the image pickup unit, which obtain the size and position of the hole to be formed in the PCB by the drill from the position of the drill and the diameter of the bit mounted on the drill, and the hole information determination and the hole information determination PCB manufacturing, including a position control unit for adjusting the position of the drill so that the center of the hole to be formed by the drill coincides with the center of the hole by comparing the position and size of the additionally obtained hole, and determining the adjusted position as the reference position of the drill. It can improve productivity by saving work time, and can reduce defects and reduce production cost, which brings great efficiency in all industries using PCB. Let.

It can be seen that the following advantages arise using the present invention.

a. Productivity improvement due to saving work time

Existing methods that rely solely on the senses of experienced operators can perform this work after the operator has seen several corrections. However, the apparatus according to the present invention is time-saving because it is possible to work in earnest by presenting accurate correction data in a single test.

This time saving not only reduces labor, but also saves the time that a defective product is generated and needs to be reworked by that amount.

Therefore, it can make a huge contribution to improving productivity.

b. cut down the money

In simple comparison, if 100 products are produced in one hour and the defective rate is 50%, two hours of work time is required to produce 100 good products.

However, if the product is produced for two hours without defects, 200 pieces of good products are actually produced. Over time, the volume of output continues to double, but there is a huge difference in value.

This increase in productivity due to the invention of new inspection equipment can result in huge financial benefits for manufacturers. In addition, it not only eliminates the supplier's damages from the delivery of defective products, but also provides the effect of delivering defective products on time.

Claims (11)

In the device for determining the position of the PCB machining drill and PCB design value for a PCB including a circular hole that is the position reference of the drill operation, An image pickup unit for capturing an image including the hole; A hole information determination unit for obtaining a size and a position of a hole to be formed in the PCB by the drill from the position of the drill and the diameter of a bit mounted to the drill; And The position and size of the hole picked up by the image pickup unit are compared with the position and size of the hole obtained by the hole information determination unit, and the position of the drill is adjusted so that the center of the hole to be formed by the drill coincides with the center of the hole. Device for determining the position and PCB design value of the drill for PCB processing comprising a; position control unit for determining the position as the reference position of the drill; The method of claim 1, The image pickup unit is a device for determining the position and PCB design value of the drill for PCB processing, characterized in that for imaging the image using the X-ray. The method of claim 1, Wherein the position control unit PCB when the surface of the PCB in the XY coordinate plane to adjust the position of the drill or to change the position of the PCB independently or for each axis of the X axis and Y axis moving simultaneously or two axes Device for determining the position of the drill and the PCB design value. The method according to claim 1 or 3, When the image pickup unit needs to adjust the magnification of the image, the image pickup unit determines the position of the PCB processing drill and the PCB design value, characterized in that it can move in a direction perpendicular to the surface of the PCB to adjust the magnification of the image. Device. The method of claim 1, The PCB has a rectangular shape, and the center hole located at the center of the PCB, the Y-axis setting hole located at the PCB on the Y axis when setting the XY coordinates with the center hole as the origin, and the four corners of the PCB relative to the center hole. When including a test hole located at the same coordinates, the portion to form the hole by the PCB drill operation is predetermined, when the drill is composed of a plurality corresponding to the test holes, The image capturing unit captures an image of the holes, The position control unit is a device for determining the position and PCB design value of the PCB machining drill, characterized in that for determining the coordinates of the PCB surface in the X-Y plane with the center of the center hole as the origin. The method of claim 5, The position controller generates coordinates by constructing an XY plane based on a previously generated Y axis when a difference between the straight line generated after the origin and the center of the Y axis setting hole and the Y axis of the XY plane occurs. Device for determining the position of PCB machining drill and PCB design value. The method of claim 5, The hole information determination unit obtains the size and position of the holes to be formed in the PCB by the drills from the positions of the drills and the diameter of the bit mounted in each drill, The position control unit compares the position and size of the hole photographed by the image photographing unit with the position and size of the hole obtained by the hole information determining unit, and the centers of the holes photographed by the image photographing unit corresponding to the centers of the holes to be formed by the drill. Adjusting the position of the PCB or drill to match the, and determine the position of the drill for PCB machining and PCB design value, characterized in that for determining the adjusted position as the reference position of the drill. The method of claim 7, wherein The position controller is a first origin, which is the center of the test holes, determined from the coordinates of the test holes, a coordinate axis based on the first origin, and a second, which is the center of the holes to be formed by the drill obtained by the hole information determination unit. Determining the position of the drill for PCB machining and the PCB design value, characterized in that the drill is moved in parallel or in rotation or simultaneously in parallel and in rotation according to the positional relationship with the coordinate axis based on the origin and the second origin. Device. The method of claim 8, The position control unit is a device for determining the position and PCB design value of the drill for PCB processing, characterized in that each of the drills can be moved independently of the other drills. The method according to any one of claims 7 to 9, The position controller displays an error if the center of the holes to be formed by the drill cannot be matched to the centers of the corresponding photographed holes by moving the drills. Device to determine. The method of claim 10, The position controller outputs a value for adjusting an interval between the photographed holes by comparing a polygon composed of the centers of the holes due to the drills with the polygon composed of the photographed holes when displaying an error. Device for determining the position of PCB machining drill and PCB design value.

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