JP3645583B2 - Mounting quality analysis method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a mounting quality analysis method for determining a defect factor in an inspection of a mounting process for mounting a component on a substrate.
[0002]
[Prior art]
Conventionally, as shown in FIG. 4, a measurement value database 1 is connected to a mounting facility group 10 via a network (communication path) 18. In the measurement value database 1, inspection data acquired from the printing equipment 11, the printing inspection machine 12, the mounting equipment 13, the mounting position inspection machine 14, the soldering equipment 15, the soldering inspection machine 16, and the electrical characteristic inspection machine 17 are stored. Accumulated. Further, as shown in FIG. 5, the specific data contents of the measurement value database 1 indicate the board number assigned to each board to identify and manage the printed board, and the contents of defects as attributes. A defect code, a measurement data value, a circuit number for specifying a component mounting position to be measured, an inspection date, and the like are recorded for each facility.
[0003]
Then, the quality manager appropriately expresses the measurement value database 1 periodically recorded from the mounting equipment group 10 in a management chart, and based on this, qualitatively determines the correlation of the cause of the defect, and the quality of the printed circuit board. Is managing.
[0004]
[Problems to be solved by the invention]
However, when data is simply expressed in a control chart and used for quality analysis, there are the following problems.
[0005]
First, in order to analyze the cause of defects, it is necessary to clarify the correlation between measured values of defects between facilities, but the control chart alone requires a lot of work and is not practical. .
[0006]
Second, in order to determine the cause of failure, it is necessary to compare the measurement data with the standard evaluation value. However, there are various evaluation criteria for each cause of failure, and the evaluation points to be analyzed are also fixed. It is impossible to set an evaluation standard.
[0007]
Thirdly, defects often occur gradually with changes in equipment consumable parts and construction methods over time, and it is difficult to narrow down the factors without statistically analyzing measured value data.
[0008]
The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a mounting quality analysis method capable of accurately and easily narrowing down a failure of a substrate and narrowing down a cause of a failure in a component mounting process on the substrate.
[0009]
[Means for Solving the Problems]
The mounting quality analysis method according to the present invention uses a database that manages an attribute data group at a mounting position for each mounting position of a component on a board in an inspection of a mounting process for mounting the component on the board, and is for arbitrary attribute data. A first step for obtaining a set of mounting positions corresponding to the evaluation range, a second step for obtaining a set of mounting positions corresponding to the evaluation range by changing the evaluation range, and a set and a second step obtained in the first step A third step for obtaining a common part between the obtained sets and a fourth step for obtaining a correlation between the evaluation ranges from the ratio of the number of mounting positions of the common part to the total number of mounting positions of both sets. It is. Further, the second step may be performed a plurality of times with different evaluation ranges .
[0010]
[Action]
According to the present invention, a plurality of evaluation ranges are set for the attribute data group set for each mounting position of the board, and all the target mounting positions of the common part of the set of mounting positions corresponding to the evaluation ranges are set. The correlation between the evaluation ranges can be quantitatively grasped from the ratio , and defect analysis and defect factor narrowing can be easily performed.
[0011]
【Example】
Hereinafter, an embodiment of a mounting quality analysis method according to the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected and demonstrated to what performs the effect | action similar to FIG. 4, FIG.
[0012]
FIG. 1 shows a flowchart of an implementation quality analysis method of this embodiment, FIG. 2 shows the contents of the evaluation table, and FIG. 3 shows the relationship between the evaluation range and the coordinate set.
[0013]
As shown in FIG. 2, the evaluation table 3 created from the measurement value database 1 includes coordinate data (a ₁ , a ₂ ,... A _N ) indicating the mounting position 5 on the printed circuit board 4 and each mounting position. It is expressed as a group consisting of five attribute data groups (b, c, d, e). The attribute data group includes statistical amount data of the measurement time zone T (t _{1 to} t ₂ ). Since any mounting position 5 on the printed circuit board 4 has a one-to-one correspondence with the circuit number, the coordinates may be referred to as a circuit number. The attribute data set corresponding to define one coordinate is determined uniquely manner. For example, the attribute data group corresponding to the coordinate a ₁ is composed of a set of (b _{11 to} b _1N , c _{11 to} c _1N , d _{11 to} d _1N , e _{11 to} e _1N ).
[0014]
FIG. 3 shows a relationship between a certain evaluation range S in arbitrary attribute data and a coordinate set E that satisfies the evaluation range S. For example, the defect definitive evaluation range S ₁ in the mounting position inspection machine 14. Further, the particular cassette number of mounting equipment evaluation range S _2. Set of coordinates of each corresponding to the evaluation range S ₁ and S _2, since that can be represented by E _1, E _2, the intersection E of the set of coordinates E ₁ and E ₂ is the intersection of both dependencies. If the number of mounting coordinates in this common set E is expressed by n (E ₁ Ｅ E ₂ ) and divided by the number of target coordinates n (E ₁ ∪ E ₂ ), the degree of dependence between S ₁ and S ₂ is shown. An index is required. That is, in the above example the degree of defect definitive in mounting position inspection machine 14 is dependent on the particular cassette is determined quantitatively. By obtaining the degree of correlation in this way, it is possible to clarify the causal relationship of defects quantitatively. It is obvious that two or more conditions for the evaluation range S are possible.
[0015]
Hereinafter, with reference to the flowchart of FIG. 1, in step # 1, an attribute data group in the measurement time zone T is extracted from the quality management database 1, and an evaluation table 3 is created as shown in FIG.
[0016]
Further, when the number of evaluation range S and M, Step # 2 at # 3, obtains the set of coordinates E _N that satisfy the evaluation range S _N until N = M. In step # 4, common coordinates of E _{1 to} E _M are obtained. Then, in step # 5, the number of common coordinates obtained in step # 4 is divided by the total number of coordinates E _{1 to} E _M to obtain the correlation frequency. The cause-and-effect relationship between defects can be quantitatively determined based on the correlation frequency between the evaluation ranges, and defect analysis and defect factor narrowing can be easily performed.
[0017]
【The invention's effect】
According to the mounting quality analysis method of the present invention, as is clear from the above description, a set of mounting positions corresponding to a certain evaluation range in an arbitrary attribute data group is obtained, and the mounting position obtained by changing the evaluation range. By finding the common part between sets, and obtaining the correlation between the evaluation ranges from the ratio of the common part, the correlation of the defect can be easily obtained quantitatively, so anyone can easily identify the cause of the defect be able to.
[Brief description of the drawings]
FIG. 1 is a flowchart of an embodiment of a mounting quality analysis method of the present invention.
FIG. 2 is an explanatory diagram of a configuration of an evaluation table of the same example.
FIG. 3 is an explanatory diagram of a relationship between an evaluation range and a coordinate set in the same example.
FIG. 4 is a configuration diagram of a quality management system in a conventional mounting facility.
FIG. 5 is a configuration diagram of measurement value data of a conventional example.
[Explanation of symbols]
1 Quality Control Database 3 Evaluation Table 4 Printed Circuit Board 5 Mounting Position S ₁ and S ₂ Evaluation Range E ₁ and E ₂ Coordinate Set E Common Set

Claims (2)

In the inspection of the mounting process for mounting components on a board, a set of mounting positions corresponding to a certain evaluation range in arbitrary attribute data is used using a database that manages attribute data groups at the mounting positions for each mounting position of components on the board. A common part between the first step to be obtained, the second step to change the evaluation range and obtain a set of mounting positions corresponding to the evaluation range, and the set obtained in the first step and the set obtained in the second step A mounting quality analysis method comprising: a third step to be obtained; and a fourth step to obtain a correlation between evaluation ranges from a ratio of the number of mounting positions of the common part to the number of all target mounting positions in both sets. 2. The mounting quality analysis method according to claim 1 , wherein the second step is performed a plurality of times with different evaluation ranges .

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