JPH0545967B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for creating numerical control data for component mounting, which is necessary when, for example, an electronic component automatic insertion machine automatically inserts an electronic component.

[Background of the invention]

Conventionally, numerical control (NC) for component insertion is used to automatically insert electronic components using automatic electronic component insertion machines.
Data is often created manually. Even when parts are automatically created using a computer, there are few cases in which mechanical interference between the automatic insertion machine and the already inserted parts is checked during insertion. At this time, an automatic insertion machine is used to actually check for interference while inserting parts one after another, which requires a lot of effort to check and correct data when interference occurs. Furthermore, even when checking for interference using a computer, the insertion order is determined in advance and interference is checked when parts are inserted in that order. The decline in the percentage of parts that can be automatically inserted using automatic insertion machines was considered to be unavoidable to some extent.

[Purpose of the invention]

In order to solve the above-mentioned problems, an object of the present invention is to provide numerical control data for component mounting that can improve the efficiency of creating component insertion NC data, increase the reliability of the same data, and improve the automatic insertion rate. The purpose is to provide a method for creating it.

[Summary of the invention]

A method for creating numerical control data for component mounting according to the present invention is a method for creating numerical control data for component mounting, in which each component to be automatically mounted on a printed circuit board by an automatic component mounting device is used in an information processing system having a data input/output device, a storage device, and an arithmetic device. Assembly information including the mounting position and mounting direction of each part and component information including the shape and dimensions of each part are stored in the storage device, and the mounting order of the parts is determined based on the pre-stored process order information. When each component is mounted, mechanical interference between at least one of the component's mounting means and the component and other mounted components is checked based on the assembly information and component information, and the result of the check is When mechanical interference occurs, in order to avoid the mechanical interference, at least one of the set order information, the mounting means, and the orientation of the component to be mounted is changed, and numerical control is performed for automatic mounting of the component. It is designed to automatically create and output data.

In addition, the following is a supplement to this. Regarding the above, to specifically explain the case of so-called automatic insertion of electronic components, when inserting a component, check for mechanical interference between the insertion head of the automatic insertion machine and a component that has already been inserted or another component that is inserted by the same machine. Insertion work precedence relationship (for example, when inserting part i, if part i cannot be inserted because the previously inserted part j interferes with the machine, part i should be inserted before part j. In terms of meaning, the insertion order relationship between parts expressed as part i → part j)
Create. From the insertion work precedence relationship created in this way, a group of uninsertable parts that cannot be inserted in any insertion order is determined. Here, for example, part i → part j, part j → part k,
When there is an insertion work precedent relationship of part k→part i, parts i, j, and k constitute a non-insertable parts group. Next, try changing the insertion process and direction of some of the parts included in the non-insertable parts group. For example, if the component has no polarity, such as a resistor, insert the component in the opposite direction. At this time, the insertion head of the automatic insertion machine also rotates 180°, so there is a possibility that mechanical interference can be avoided. As a result, a final work precedence relationship is created without any non-insertable component groups, and the insertion order is determined based on this constraint.

This aims to improve the efficiency of creating part insertion NC data, improve data reliability, and improve automatic insertion rate.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a configuration diagram of a computer system used in an embodiment of the method for creating numerical control data for component mounting according to the present invention. A detailed description will be given below using an example related to component insertion. Here, the processing device 1 is
In order to execute this method, various calculations are performed in the central part, including a magnetic disk device 2 for storing (memory) assembly information, parts information, etc., a floppy disk drive device 3 for inputting assembly information, A display device 4 for registering component information and displaying and modifying processing results, a paper tape puncher 5 for outputting component insertion NC data, and a line printer 6 for printing out processing results are connected. The present invention relates to a method of creating these output component insertion NC data, and is intended to enable component insertion while avoiding mechanical interference.

First, assembly information and parts information will be explained.

As shown in the explanatory diagram of FIG. 2, the assembly information is composed of one board information record for each printed board and as many parts records as the number of parts used in that board. Each component record includes data items such as the component name, insertion position, and insertion direction of the electronic component, and is usually created using a printed circuit board design system (CAD (Computer Aided Design)) and recorded via a floppy disk. entered into the system. Here, the insertion position indicates the X and Y coordinates on the printed circuit board of a reference point determined for each component type. Further, the insertion direction indicates the rotation angle when rotating and inserting the component from a reference direction determined for each component around a reference point. The parts record also has data items for the insertion process and insertion order for later use. These two data items do not have fixed values at the time they are created by CAD.

Such electronic components include chip components, IC
There are parts, resistors, coaxial parts such as diodes, vertical parts (capacitors, transistors, etc.), etc.

As shown in the explanatory diagram of FIG. 3, the component information stores component names, insertion process classifications, component dimensions, and presence or absence of polarity for all components handled by the system. Here, the insertion process classification indicates which process the part can be inserted in depending on the type of the part.For example, if it is an IC part, it is used with an IC part insertion machine, and if it is a coaxial part, it is used with a coaxial part insertion machine. As shown in Figure 3, it shows a machine that is generally used for mounting parts.

The above data is stored in an assembly information file and a parts information file in the magnetic disk device 2, respectively.

The component insertion NC data creation method of the present invention is based on the above-described configuration and determines the insertion process and insertion order in the following steps.

That is, as shown in the schematic explanatory diagram of the procedure in FIG. 4, this method includes (1) provisional determination of insertion process, (2) determination of insertion work precedence relationship (interference check), and (3) change of insertion process and insertion direction. , (4) Insertion order determination, (5) Parts insertion
It consists of five steps: NC data creation.

The functions will be explained step by step below.

(1) Temporary determination of insertion process Search the parts information file using the part name of each part record in the assembly information as a key, tentatively determine the insertion process based on the insertion process classification of the part, and determine the insertion process of the part record in the assembly information. Write the insertion process classification to the insertion process data item. The insertion process determined here may be modified by changing the insertion process in (3).

(2) Determining the precedence relationship of insertion work (interference check) As mentioned earlier, interference refers to interference between the insertion head of the insertion machine and the inserted parts that have already been inserted when automatically inserting parts. means interference. In addition, the insertion work precedence relationship is a condition regarding the insertion order of two parts i and j, and the insertion work precedence relationship (part i → part j) means that if part j is inserted before part i, the parts This indicates that component i should be inserted before component j because it interferes with component j when inserting component i.

There are several interference checking methods, one of which is a simple method that will be described below. The basic idea behind this interference check is that when inserting a certain part, the area required by the insertion head of an automatic insertion machine (insertion work space) and the area where the part exists (part area) are separated into a plane of simple shape. The interference is checked by determining the interference using figures (for example, rectangles and circles) and checking the overlap of these figures. Here, the plane figure of the above component area is the bird's-eye view (cross-sectional) shape of the component when mounted on a printed circuit board, and is generally a chip component,
IC parts, coaxial parts, etc. are rectangular, and vertical parts etc. are circular.

FIG. 5 is an explanatory diagram of an interference check during insertion in this method. Part m by insertion head P
When inserting into the substrate Q, the position of the insertion head at the time of insertion is P', as shown in FIG. 5a. In this case, when parts k and l have already been inserted, part l interferes with the insertion heads P and P'. Fifth
As shown in Figure b, on a plane, a component area M of a component m, a component area K of a component k, a component area L of a component l,
and the insertion work space N of part m,
The interference check is performed by checking the overlapping state of these figures K to N. here,
Since the insertion work space N of part m overlaps with the part area L of part l, the insertion work precedence relationship (part m→part l) can be determined. As can be seen from FIG. 5, the size of the insertion work space N needs to be changed depending on the height of the parts located around it. Therefore, first find the insertion work space assuming that the surrounding parts have the greatest height among all the parts, use this to check the overlapping condition, and if there are overlapping parts, the height of the parts is It is possible to correct the insertion work space to a smaller size accordingly and check the overlap again.

Above, we have described a method for interference checking in which the insertion work space and component area are represented by simple plane figures such as rectangles and circles, and interference is investigated by the overlapping state of these figures. It is also possible to express each object as a combination of rectangles, circles, etc., or to express it as a three-dimensional object such as a rectangular parallelepiped, cylinder, etc., and a combination thereof, and to investigate interference based on the overlapping state of the objects.

An example of an algorithm for checking figure overlap will be described in the case where the component area is a rectangle or a circle.

First, if the figures are rectangles, one rectangle is used as a reference, and the right-angled area (including the same rectangle) is defined by both sides that intersect at the lower left point (lower left vertex) and the upper right point (upper right vertex). a right-angled area defined by both sides that intersect at a vertex) (including the same rectangle)
If there is another rectangle in either of them, the two rectangles will overlap each other.

In addition, if the shapes are a rectangle and a circle, set an area around the rectangle with a width equivalent to the radius of the circle, and if the center of the circle is within this area and within the same rectangle, the rectangle and the circle shall overlap with each other.

Further, in the case where the figures are circles, if the distance between the centers of each circle is less than or equal to the sum of the radii of both circles, the circles are assumed to overlap each other.

Next, FIG. 6 is a flowchart of the insertion work precedent relationship determination (interference check) process in this method. The processing contents at each step will be explained below.

(Step 1) Using the component dimension data in the component information, find the component area for all inserted components in the assembly information.

(Step 2) The insertion work precedence relationship determination is performed for each process in order, and the target process (target process) is determined from the previously specified process order. When the insertion work precedence relationships have been determined for all processes, the entire process ends.

(Step 3) From all inserted parts, according to the contents of the insertion process data item of the parts record in the assembly information,
Parts inserted in the target process (target process insertion parts)
and parts inserted in a process before the target process (inserted parts).

(Step 4) Find the insertion work space for all target process insertion parts.

(Step 5) Select one part from the parts to be inserted in the target process.
If all parts are selected, return to step 2.

(Step 6) Check the overlap between the insertion work space of the selected part and the part area of all target process insertion parts other than the inserted part and the selected part. Here, the range exceeding the board size and the range used by the board holder and board loader are also treated as insertion restriction areas, equivalent to the component areas of inserted components.

(Step 7) After finding the insertion work precedence relationship from the result of step 6 and registering it in the insertion work precedence relationship file on the magnetic disk, return to step 5.

(3) From the insertion work precedence relationship created in (2), find parts that will interfere with each other even if the insertion order is changed (non-insertable parts group), and display this on the display. For example, the insertion process and insertion direction are changed by the designer. Although this process is also performed for each process, a group of parts that cannot be inserted occurs in the following two cases.

(i) When there is an insertion work precedence relationship of part i → part j, and the insertion process of part j is before the insertion process of part i.

(ii) Even if the parts are inserted in the same process, there is a preceding insertion work relationship such as, for example, part i → part j and part j → part i. Even if there are 3 or more parts, part k → part l, part l → part m, part m
→If there is a preceding insertion operation called part k.

As a countermeasure in such a case, ○B How to change the insertion process ○B How to change the insertion direction There is.

When changing the insertion process, for example, if there is an insertion work precedence relationship of part i → part j, and the insertion process of part j is before the insertion process of part i, the insertion process of part j is changed to the insertion process of part i. If it is changed after , there is an insertion order that satisfies this insertion work precedence relationship. Furthermore, for example, if the insertion process of part i is changed to a manual assembly process, the insertion work space can be reduced, so that the insertion work precedence relationship of part i → part j may disappear.

When the insertion direction is changed, for example, when there is a preceding insertion work relationship of part p → part q, part p
If there is no polarity, it is also possible to rotate the insertion direction of the component p by 180 degrees with the insertion head. Furthermore, as shown in Figure 5b, the part M is generally held on the insertion head along one edge (the N edge), so even if there is polarity, the part cannot be rotated 180° on the insertion head. If you do this, you can insert the correct polarity in the same way. Therefore, the insertion work space for part p changes, so part p→part q
There are cases where the insertion work precedence relationship disappears.

Regardless of which method is adopted, the overall insertion work precedence relationship changes, so it is necessary to re-execute the step (2) of determining the insertion work precedence relationship (interference check).

One way to find a group of parts that cannot be inserted in the same process and which will cause interference no matter what order they are inserted from the insertion work precedence relationship created in (2) is as follows using graph theory. The applied solution method is shown.

In this solution method, each insertion operation (inserted part) is
Express the insertion work precedence relationship in a directed graph with the insertion work precedence relationship as an edge (in the direction of the arrow). FIG. 7 is a directed graph of the insertion work precedence relationship in this method, and a is a graph in which, as an example, there is the insertion work precedence relationship shown in the figure for nine types of parts 11 to 19. If we find a strongly connected part on this graph, that is, a set of vertices that can be reached by following the edges, this becomes a set of non-insertable parts groups. For example, part 12, part 1
3. The component 14 is one non-insertable component group, and these three components do not have an insertion order that satisfies the insertion work precedence relationship. The same thing can be said about the set of parts 18 and 19.
Such non-insertable component groups can be easily determined using known graph theory.

By changing the insertion process and insertion direction as described above, it is possible to exclude all non-insertable component groups and create a final insertion work precedence relationship. For example, in FIG. 7a, the insertion process of component 12 is changed to a later insertion process, and
If you change the insertion direction of 9, part 11 → part 1
2. Part 12 → Part 13, Part 14 → Part 12,
Since the insertion work precedence relationship of component 19→component 18 is eliminated, it is possible to create a final directed graph of the insertion work precedence relationship in which there is at least one insertion order, as shown in FIG. 7b.

Above, we have described a method in which the insertion process and insertion direction are changed based on the designer's judgment in an interactive manner as an example, but this designer's judgment is based on the assembly information shown in Figure 2 and the parts information shown in Figure 3. For parts (groups) that cannot be inserted,
By repeating the insertion process, changing the insertion direction, and determining the insertion work precedence relationship one after another, it is also possible to obtain the insertion work precedence relationship without any non-insertable component groups.

(4) Determination of insertion order Once the final insertion work precedence relationship is determined in (3), there is always an order in which the target process insertion parts can be inserted while satisfying these constraints. In the insertion order determination step, the optimal insertion order is determined from among these insertion orders. For example, the moving distance of the insertion head during insertion (the moving distance of the XY table of the insertion machine)
There are methods such as considering the insertion order that minimizes the sum of , and it can be solved using the known traveling salesman problem.

(5) Creation of component insertion NC data Since the insertion process has been determined in (3) and the insertion order has been determined in (4), component insertion NC data can be created for each insertion machine according to this. This is possible using known technology.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to automatically generate numerical control data for component mounting in consideration of machine interference during automatic component mounting. This method eliminates the need to check data using a machine, and since the insertion process, insertion order, etc. are determined by taking into account the preceding relationship of insertion operations, the automatic insertion rate can be improved, and other effects are remarkable.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a computer system used in an embodiment of the method for creating numerical control data for parts insertion according to the present invention, and FIG. 2 is an explanatory diagram of its assembly information.
Fig. 3 is an explanatory diagram of the same component information, Fig. 4 is an explanatory diagram of the same general procedure, Fig. 5 is an explanatory diagram of the interference check at the time of insertion in this method, and Fig. 6 is also an explanatory diagram of the insertion work preceding the same. The flowchart of the relationship determination (interference check) process in FIG. 7 is also a directed graph of the insertion work precedence relationship. 1...processing device, 2...magnetic disk device, 3
... Floppy disk drive device, 4 ... Display device, 5 ... Paper tape puncher, 6 ... Line printer.

Claims (1)

[Claims] 1. In an information processing system having a data input/output device, a storage device, and an arithmetic unit, assembly information including the mounting position and mounting direction of each component for parts to be automatically mounted on a printed circuit board by an automatic component mounting device, and Component information including the shape and dimensions of each component is stored in the storage device, mounting order information of the component is set based on pre-stored process order information, and when mounting each component, a mounting means for the component is stored. Check for mechanical interference between at least one of the parts and other mounted parts based on the assembly information and the parts information, and if mechanical interference occurs as a result of the check, to avoid the mechanical interference. , changing at least one of the set order information, the mounting means, and the orientation of the component to be mounted, and automatically creating and outputting numerical control data related to automatic mounting of the component. How to create numerical control data for mounting parts.