JP4667681B2 - Mounting inspection system and mounting inspection method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inspection apparatus and method for inspecting cream solder and printed component printed on a printed circuit board at high speed for deviation or presence of components.
[0002]
[Prior art]
Due to the recent reduction in size and weight of electrical products, there is a significant reduction in the size of printed circuit boards, which are the main components of electrical products, and the mounting density of components increases as the printed circuit boards become smaller. Human visual inspection is becoming difficult. For this reason, an inspection apparatus that automatically inspects these printed circuit boards is desired. However, a higher-speed inspection apparatus is required as production tact is improved.
[0003]
For example, the image inspection apparatus disclosed in Japanese Patent Laid-Open No. 05-006422 meets such requirements. As shown in FIG. 13, the image inspection apparatus uses a line sensor that can ensure a wider imaging range as compared with an area sensor, and inspects various inspection items in parallel while capturing image data. High-speed inspection was realized. The configuration and operation of a conventional inspection machine will be briefly described with reference to FIG.
[0004]
The image inspection apparatus is obtained from a color line sensor camera 10 that captures image data of the inspection object while moving relative to the inspection object, and a linear scale 39 that measures a relative movement distance from the inspection object. Further, based on the relative movement distance of the inspection object, the acquisition memory 44 that starts and ends the acquisition of image data from the color line sensor camera 10 and the inspection object area of the inspection object from the acquired image data. A cut-out memory 45 that cuts out and stores image data, an image processing circuit 46 that processes the cut-out image data into image processing data, and a plurality of inspection processes that perform inspections on various inspection items using the image processing data Circuit 47. Then, the image inspection apparatus inspects various inspection items in parallel while taking in the image data. Conventionally, using such an image inspection device, a cream solder printing inspection machine that inspects the printing state of solder after cream solder printing, a mounting component inspection device that inspects the mounting state of the component after component mounting, and soldering after soldering by reflow etc. A quality inspection of the printed circuit board was performed by an appearance inspection apparatus that inspects the bonding state.
[0005]
[Problems to be solved by the invention]
However, in the conventional inspection machine, after a chip size package or quad flat package implementation, there is a problem that can not be inspected under the chip size package or quad flat package (between the chip size package or quad flat package and the substrate).
[0006]
[Means for Solving the Problems and Effects of the Invention]
In order to solve the above problems, a mounting inspection system according to the present invention includes an imaging unit that images a substrate, and a component that processes a captured image obtained by the imaging unit and inspects the mounting state of the component mounted on the substrate. A mounting inspection apparatus including inspection means, solder inspection means for processing a captured image and inspecting solder printed or applied on a substrate, a first mounting machine for mounting chip components, and a chip size package or quad flat A second mounting machine for mounting the package, a mounting inspection device is disposed between the first mounting machine and the second mounting machine, and the solder mounting means is configured such that the second mounting machine is a chip size package or a quad flat. in the region on the substrate for mounting the package, characterized in means der Rukoto having a function to check the presence or absence of a foreign object based on a solder area That.
[0007]
Further, the mounting inspection method of the present invention includes a first mounting step for mounting a chip component in a first mounting region on the substrate, an inspection step for inspecting the substrate after the first mounting step, and a second on the substrate after the inspection step. A second mounting process for mounting a chip size package or a quad flat package in the mounting area, and the inspection process is a process for inspecting a component mounting state in the first mounting area and inspecting solder in the second mounting area. Ah is, the inspection process, in a first mounting region checks the mounted state of the part, in the second mounting region and wherein the step der Rukoto detecting the presence or absence of the foreign object based on the area of the solder as well as inspect the solder To do.
[0008]
As described above, according to the present invention, even after a chip size package or quad flat package implementation, examining the bottom of the chip size package or quad flat package (between the chip size package or quad flat package and the substrate) Is possible.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an inspection machine according to an embodiment of the present invention will be described with reference to the drawings. In addition, the same reference number is attached | subjected to the same component as a prior art example, and description is abbreviate | omitted. FIG. 1 shows a component mounting line according to the configuration of an inspection machine according to an embodiment of the present invention, and FIG. 5 shows a part of a printed circuit board that is an inspection object in the inspection machine.
[0010]
As shown in FIGS. 1B and 5, the inspection machine 8 prints the cream solder 25 on the printed circuit board 30 with the printing machine 7, and then mainly mounts the small chip component 24 with the chip mounter 5. The printed circuit board 30 is used as an inspection object, and is used for an inspection process of a component mounting line.
[0011]
Next, an example of inspection items performed by the inspection machine 8 will be described. 10 shows an example of inspection items related to component mounting performed by the inspection machine 8, and FIG. 11 shows an example of inspection items related to solder state performed by the inspection machine 8.
[0012]
10 and 11, as inspection items related to component mounting, the inspection machine 8 includes a component presence / absence of the small component 24 mounted by the chip mounter 5 (FIG. 10A), and a positional deviation of the small component 24 (FIG. 10 ( b)), and the rotation deviation (FIG. 10C) of the small component 24 is inspected. Along with them, the inspection machine 8 bleeds the cream solder 25 of the chip size package (CSP) or the quad flat package (QFP) mounted in the downstream process as an inspection item related to the solder state (FIG. 11A), Inspection of blur of cream solder 25 (FIG. 11B), printing misalignment of cream solder 25 (FIG. 11C), and detection of foreign matter scattered on cream solder 25 of CSP or QFP (FIG. 11D) Is to do.
[0013]
FIG. 2 is an external view of an inspection machine according to an embodiment of the present invention. As shown in FIG. 2, the inspection machine is not simply a combination of two facilities, but a single control unit realizes inspection for two conventional units.
[0014]
FIG. 3 shows a control configuration diagram of the inspection machine according to the embodiment of the present invention. In FIG. 3, the inspection machine drives the color line sensor camera 10 to sequentially capture images. The images are sequentially sent to the color image processing board 16, and the images are transferred to the CPU board 17 using the image transfer mechanism (FIG. 4) in the color image processing board 16.
[0015]
Since the image is captured for each line due to the characteristics of the color line sensor camera 10, the image may be sequentially transferred to the CPU board 17 every time one line is captured. The transfer is performed every time 64 lines of images are accumulated on the processing board 16.
[0016]
Furthermore, the color line sensor camera 10 needs to be driven at a constant speed during image capture, and cannot be stopped during image capture. Therefore, as shown in FIG. 4, the color image processing board 16 includes a memory A22 and a memory B23 in order to accumulate images of the color line sensor camera 10 even during image transfer for 64 lines, and stores data for 64 lines. Each has accumulated. The color image processing board 16 alternately performs image accumulation and image transfer while sequentially switching the accumulation memory A22 and the memory B23.
[0017]
The image transferred to the CPU board 17 manages the position of the image captured by the color line sensor camera 10 and transferred to the CPU board 17 in the CPU board 17, and the image transferred to the CPU board 17 in real time. You can see the position. Further, as shown in FIG. 6, the CPU board 17 reads inspection data 26 described in advance for inspection, and the inspection data 26 exists on an image in which an object to be inspected is captured. The position coordinates are described so that the place can be understood. When the inspection object described in the inspection data 26 is taken into the color line sensor camera 10 and the image is transferred to the CPU board 17, the CPU board 17 inspects the inspection object. Therefore, it is preferable that the inspection data 26 describe an object to be inspected in the order in which images are captured.
[0018]
In general, the number of inspection points per substrate, which is an object to be inspected, is about 1000 points for parts and about 10,000 points for solders. In this case, the inspection data 26 includes 1000 part inspection data and 10000 solder inspection data. As described above, the inspection data 26 includes the component inspection data and the solder inspection data described in the order of image capture, the component or solder position data, the external dimensions, the inspection mode indicating the inspection algorithm, and the component. Alternatively, it includes a flag for distinguishing solder and a solder reference area included in solder inspection data. The inspection data 26 shown in FIG. 6A is one example, and shows 10 points of solder inspection data and 2 points of component inspection data. Based on the inspection data 26, the inspection machine 8 performs inspections in the order of serial numbers. That is, the inspection machine 8 inspects in ascending order of the numbers based on the numbers on the component and solder arrangement diagrams shown in FIG.
[0019]
The inspection machine 8 expands the inspection data 26 corresponding to the type of the printed circuit board 30 from the hard disk 21 connected to the CPU board 17 to the memory 20 of the CPU board 17 when the inspection machine 8 is started or when the type is switched. When the memory is developed, the inspection machine 8 develops the template data for component inspection for angle search, and sets a parameter for extracting solder on the color image processing board 16.
[0020]
Next, specific operations performed by the inspection machine 8 during the inspection will be described with reference to FIGS. FIG. 7 is a flowchart showing the processing operation when the inspection machine 8 performs the inspection.
[0021]
In FIG. 7, the inspection machine 8 identifies that the inspection object is the component 24 or the solder 25 based on the flag of the inspection data 26 (step S <b> 1), and based on the outer dimension value of the inspection data 26. An inspection area is set (step S2). Next, when the inspection object is the part 24, the inspection machine 8 searches the inspection area using the template described in the part data linked to the inspection data 26 (step S3). Then, the inspection machine 8 determines the evaluation value of the point having the highest evaluation value as a threshold value, and determines that there is no component if the evaluation value is equal to or lower than the threshold value (step S4). Next, when the evaluation value is greater than or equal to the threshold value, the inspection machine 8 compares the detection point with the highest evaluation value with the position coordinates of the inspection data 26, and when the evaluation value is greater than or equal to the deviation determination value, determines that there is a deviation (step S5). And the inspection machine 8 returns to step S1, and repeats a process.
[0022]
FIG. 8 is a schematic diagram showing part search and template data for explaining the processing operation of the inspection machine 8 described above. In FIG. 8, the inspection machine 8 sequentially searches the preset model data in the search area to detect the position where the closest pattern exists.
[0023]
Returning to FIG. 7, when the inspection machine 8 identifies that the inspection object is the solder 25 based on the flag, only the same component as the color of the cream solder 25 set in advance in the inspection area is extracted ( In step S6), the boundary position and area of the extracted portion are calculated by performing boundary tracking of the extracted portion (step S7).
[0024]
FIG. 9 is a schematic diagram of solder extraction and an enlarged view thereof illustrating the processing operation of the inspection machine 8 described above. In FIG. 9, the inspection machine 8 sets 1 as the portion extracted as the solder 25, 0 as the portion not extracted, and sets the portion that is 1 as the processing target. The inspection machine 8 calculates the barycentric position and area of the processing target portion by performing boundary tracking of the processing target portion.
[0025]
Returning to FIG. 7, the inspection machine 8 compares the position of the center of gravity calculated based on the processing target portion and the position coordinate area of the inspection data 26, and if it is equal to or greater than a predetermined deviation determination value, determines that there is a printing deviation ( Step S8). Next, for the fading and blurring of the solder 25, the inspection machine 8 compares the area data of the processing target portion calculated in step S7 with the reference area of the solder in the inspection data 26 to obtain a predetermined blur. If it is equal to or less than the determination value, the image is blurred. And the inspection machine 8 returns to step S1, and repeats a process.
[0026]
Incidentally, the state of the chip mounter 5 is an upstream process of inspection machine 8, foreign matters tape cut piece or the like of the chip component 24 and the component supply cassette mounting Shisonji is sometimes rest on a printed circuit board. When such foreign matter is placed on the solder 25 on which the CSP or the like is mounted, the foreign matter becomes poorly caught when the CSP is mounted in the downstream process. It is difficult to find the foreign matter, and the detection of the defect may be delayed until the product functional inspection. In the present invention, since the area of the printed solder 25 that is the mounting position is measured before the CSP or the like is mounted, when a foreign object is placed on the solder 25, the normal solder area is not calculated. Therefore, in the present invention, such foreign matter on the solder 25 can be detected before mounting.
[0027]
Some types of printed circuit boards 30 do not require high-density mounting, and therefore CSP and QFP are not mounted. In the case of such a substrate, if the printing machine 7 maintains a certain condition, it is difficult for the printing state to be deteriorated, but the deterioration of the rolling property due to the volatilization of the flux contained in the cream solder 25 and the long-term use. Since the printing state may be deteriorated due to the deterioration of the mask due to the above, it is necessary to check the condition of the printing machine 7. However, since the frequency of occurrence of defects is low, it is difficult to install a solder inspection machine downstream of the printing machine 7 in terms of investment effect. Therefore, in such a printed circuit board 30, as shown in FIG. 12, a test pattern 28 is provided in a portion where the component 24 is not mounted, and the solder inspection of this test pattern 28 is performed at the same time as the component inspection in the process after component mounting. Although it is an inspection machine, the condition of the printing press can be monitored.
[0028]
According Therefore the construction of the present invention, the inspection apparatus of one, testing and implementation state of the small parts high mounting accuracy is required, bonding failure caused by a defective printing state can not be checked after mounting components chip The printing state of a size package (CSP) or the like can be inspected at the same time, and the cause of the quality defect of the printed circuit board can be detected most effectively. In addition, the data structure is standardized and the inspection data is sequentially decoded, and the inspection of the parts and solder is automatically switched according to the target, so that the inspection can be performed in one operation. There is no need to perform the inspection in two steps, and the time required for the inspection can be shortened.
[0029]
In general, solder printing other than CSP, QFP, or extremely small parts significantly reduces the probability of occurrence of defects, so the effect of inspecting the solder printing state is low, but a test print pattern is provided on the printed circuit board in advance. By constantly inspecting the printing pattern, it is possible to quickly know the state change of the printing press. As described above, according to the configuration of the present invention, it is possible to most effectively realize quality maintenance in mounting.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a component mounting line and a conventional component mounting line example according to a configuration of an inspection machine according to an embodiment of the present invention.
FIG. 2 is an external view of the inspection machine 8 in FIG.
3 is a functional block diagram showing a control configuration of the inspection machine 8 in FIG. 1. FIG.
4 is a functional block diagram showing an image transfer configuration unit included in the color image processing board 16 in FIG. 3. FIG.
5 is a schematic view showing a part of a printed circuit board that is an inspection target of the inspection machine 8 in FIG. 1;
6 is a diagram showing an example of inspection data used by the inspection machine 8 in FIG. 1 and its layout.
7 is a flowchart showing a processing operation at the time of executing an inspection performed by the inspection machine 8 in FIG. 1;
FIG. 8 is a schematic view of component inspection performed by the inspection machine 8 in FIG. 1;
FIG. 9 is a schematic view of solder inspection performed by the inspection machine 8 in FIG. 1;
10 is a schematic diagram showing an example of component inspection items performed by the inspection machine 8 in FIG.
11 is a schematic diagram showing an example of solder inspection items performed by the inspection machine 8 in FIG.
12 is a schematic view showing a test pattern for solder inspection used by the inspection machine 8 in FIG. 1. FIG.
FIG. 13 is a functional block diagram showing a functional configuration in a conventional image inspection apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Appearance inspection machine 2 ... Reflow 3 ... Multifunctional machine 4 ... Component inspection machine 5 ... Chip mounter 6 ... Solder inspection machine 7 ... Printing machine 8 ... Inspection machine 9 ... Signal tower 10 ... Color line sensor camera 11 ... Monitor 12 ... Transport unit 13 ... Control panel 14 ... Power receiving panel 15 ... Controller 16 ... Color image processing board 17 ... CPU board 18 ... PLC / NC board 19 ... C-PCI bus 20 ... Memory 21 ... HDD
22 ... Memory A
23 ... Memory B
24 ... Component 25 ... Solder 26 ... Inspection data 27 ... Land 28 ... Test pattern 29 ... Mark 30 ... Printed circuit board 31 ... Memory board 32 ... Man-machine interface 33 ... Monitor TV 34 ... Keyboard 35 ... I / O device 36 ... Lighting equipment 37 ... Motor 38 ... Encoder 39 ... Linear scale 40 ... Linear scale count circuit 41 ... Capture memory address generation circuit 42 ... Extraction memory address generation circuit 43 ... Image processing timing generation circuit 44 ... Acquisition memory 45 ... Extraction memory 46 ... Image processing Circuit 47 ... inspection processing circuit

Claims (2)

Imaging means for imaging a substrate, component inspection means for processing a captured image obtained by the imaging means and inspecting a mounting state of a component mounted on the substrate, and processing the captured image on the substrate A mounting inspection device comprising solder inspection means for inspecting solder printed or applied to
A first mounting machine for mounting chip components;
A second mounting machine for mounting a chip size package or a quad flat package,
The mounting inspection apparatus is arranged between the first mounting machine and the second mounting machine ,
The solder inspection means is the area on the substrate on which the second mounting apparatus for mounting the chip size package or quad flat package, Ru means der having a function to check the presence or absence of a foreign object based on the area of the solder A mounting inspection system characterized by that. A first mounting step of mounting a chip component in a first mounting region on the substrate; an inspection step of inspecting the substrate after the first mounting step; and a chip size package in the second mounting region on the substrate after the inspection step Or a second mounting step for mounting a quad flat package,
The inspection process, in the first mounting area to inspect the mounting state of the component, in the second mounting region Ri step der to inspect the solder,
The inspection process, in the first mounting area to inspect the mounting state of the component, in the second mounting region, wherein the step der Rukoto detecting the presence or absence of the foreign object based on the area of the solder as well as inspect the solder And mounting inspection method.

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