CN104715109A - Automatic automobile body-in-white welding spot division method based on sphere interference - Google Patents

Abstract

The invention relates to a method for automatically dividing solder joints of an automobile body-in-white based on spherical interference, comprising the following steps: 1) constructing a panel tree structure according to the welding sequence, 2) performing hierarchical marking on each node of the panel structure tree, 3) Create a solder ball with each solder joint as the center, 4) Calculate the interference between the solder ball and the plate, and obtain the interference plate group, 5) According to the number of interference and the number of welding layers, and according to a certain division According to the principle, the solder joints are divided, and the solder joints are divided under the corresponding board assembly nodes.

Description

An automatic division method of automobile body-in-white solder joints based on sphere interference

【Technical field】

The invention is applicable to the welding process planning of automobile body-in-white and the design and manufacture of a production line, and belongs to the field of computer integrated manufacturing.

【Background technique】

The welding line of a car determines the manufacture of the car body and determines the production capacity of the car. Therefore, how to quickly deploy the welding line is very important. The emergence of digital technology has significantly changed the automotive industry. As an advanced design and production technology, it can conduct virtual reality for the layout, planning and simulation of welding in the middle and early stages, effectively improving the work efficiency of design. At the same time, the existing CAD/CAM system is more open. With the application of development technology, the integration and expansion of system functions can be realized, which provides conditions for further improving work efficiency.

Solder joint planning is one of the main contents of the welding process. Since there are as many as 4,000-5,000 solder joints in the body-in-white vehicle, and the scale is relatively large, in order to clarify the requirements for resource allocation and tempo of the production line, it is necessary to perform station-to-assembly In order to reduce the group size of solder joints, follow-up detailed work such as fixture design, welding path planning and so on. However, nearly half of the solder joints provided by the OEM will be provided in the form of a total station or even a complete vehicle. Generally, there are only the coordinate values of the solder joints and the number of welding layers (maximum four-layer welding), and all the solder joints are stored in one file without structure. Therefore, when planning the welding process, the designer will first divide the welding points into the sub-assembly according to the welding level according to the welding sequence structure tree of the plate, but now the common processing method relies on the generalized CAD system and Dividing solder joints based on human experience involves repetitive work and a large amount of work, which can easily lead to errors and affect work efficiency. Therefore, based on digital technology and development technology, it is of high practical value to invent a method for batch processing of BIW welding joints.

【Content of invention】

The purpose of the present invention is to provide a method for automatically dividing the solder joints of automobile body-in-white based on ball interference, by automatically creating solder joint balls at the solder joint positions, calculating the interference relationship between them and the tree structure plate, and based on Fig. 3 The division algorithm shown in the figure realizes the automation of solder joint division, reduces manual intervention, and significantly improves the work efficiency of process planning.

A kind of method for automatic division of solder joints of automobile body-in-white based on spherical interference proposed by the present invention comprises the following steps:

Step 1: Construct the body-in-white panels into a tree structure StructureTree (ST) according to the welding sequence;

Step 2: mark the panel structure tree hierarchically;

Step 3: Automatically create solder balls at solder joints;

Step 4: Carry out interference calculation between the solder joint ball and the tree structure plate, and obtain all the plates and their layers that interfere with it;

Step 5: According to the number of welding layers WL (Welding Layers) of the solder joint and the number of interference plates CN (Collision Number), based on the division principle shown in Figure 3, search for the correct summary from the bottom up to the plate tree node point and drag it under the node.

【Description of drawings】

Attached Figure 1 shows the panel tree structure diagram

Accompanying drawing 2 shows the figure of marking plate

Attached Figure 3 shows the flow chart of solder joint division

Accompanying drawing 4 shows to find the maximum common node figure

【Detailed ways】

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The automobile body panels are assembled into a tree structure according to the welding sequence, as shown in Figure 1. Set the root node level BodyLevel (BL) of the tree structure to 1. If a node is a k node, read the child node and record it as k+1 until the marking of the board tree structure is completed, as shown in Figure 2 shown.

Read the coordinate information of the solder joints, and given a diameter of 10mm (approximately the diameter of the actual welding nugget), create a sphere WSBall (WB) with all the solder joints at their positions.

Calculate the interference between the solder ball of the i-th solder joint (denoted as WB_i) and PT, and obtain all panel groups PanelGroup (Panel_1, Panel_2,...,Panel_n) that interfere with WB_i, and each panel in the PanelGroup in ST In the level array BLGroup(BL_1, BL_2,...,BL_n), its Panel_i and BL_i are recorded as the i-th interference plate and its level number.

Through the above operations, the welding layer information WL of all solder joints, the interference panel group PanelGroup and the total number of interference CN can be obtained. Finally, according to the relationship between WL and CN, the division principle is established, and the welding process is divided according to the division process shown in Figure 3. point division. The division process involves finding the "maximum common node" method, the principle is shown in Figure 4, and the specific steps are as follows:

Step 1: Obtain the minimum level number MinLevel of the plate interference group of each solder joint.

MinLevel＝Min(BL ₁ ,BL ₂ ,...,BL _x ) (1)

Step 2: Determine the starting search position StartPos of all interfering panels in the interfering group PanelGroup. Taking the jth board as an example, its initial search position is the current node where the board is located, and its BL _j -MinLevel+1 generation parent node is retroactively obtained;

Step 3: Find common nodes. After step 2, the number of levels BL of the initial search position of each board is the same, therefore, each board can search for the parent node synchronously until the same node is found, at this time the output node is the largest common node.

The specific content of the principle of solder joint division is as follows:

1. The number of interference plates CN<2, no division;

2. The number of interfering plates CN = the number of welding layers WL of the solder joints, then find the largest common node of the interfering plates, and divide the solder joints under it;

3. If the number of interfering plates CN>the number of soldering layers WL and CN-WL>WL, then the C _cn ^wl group is established to contain WL plate arrays, and the maximum common node is calculated, and then the C _cn ^wl group can be generated Node group, and find the node with the largest number of levels in this node group, and divide the solder joint under its node.

4. No division in other cases.

Considering that in the process of automobile welding, it is impossible to completely realize the division due to the problems such as secondary loading of the welding plate, but such cases are special and relatively rare. Using the above work can greatly reduce the scale of welding joint division and realize The automatic division of more than 90% solder joints has high efficiency and high practical value.

The above is a description of the present invention and its implementation, but it is not limited thereto. Without departing from the purpose of the present invention, any design of a structure or embodiment similar to the technical solution without creation belongs to the protection scope of the present invention.

Claims (3)

1., based on the automobile body-in-white solder joint Automated Partition Method that ball is interfered, it is characterized in that, comprising:

Analyze the vehicle body digital-to-analogue and solder joint data that import CAD system, the plate model of tree structure is built according to welding sequence, and level mark is carried out to it, simultaneously, read solder joint coordinate figure and create solder balls in its position, ball and plate model are carried out interference analysis, find out the plate of interference, again by interfering sum, the number of levels of each plate and the layer number of solder joint carry out judge decision-making, in one group of plate of interfering, search plate corresponding to this solder joint and the darkest common node of these plates in structure tree, under this solder joint is divided into this node, all solder joints are operated equally, and the division of all solder joints can be completed.

2. method according to claim 1, is characterized in that, described reading solder joint coordinate figure also creates solder balls in its position, itself and plate model is carried out interference analysis, finds out the plate of interference, specifically comprise:

By reading the coordinate information of solder joint, for simulation actual welding, create the solder balls of nugget size diameter at bond pad locations place, carry out interference treatment by this ball and all plates, obtain all plates of interfering with ball, namely obtain welded plates that may be corresponding with this solder joint.

3. method according to claim 1, is characterized in that, the division of described solder joint, specifically comprises:

The division of solder joint to specifications following principle divides:

1. interference plate number of packages CN<2, does not divide;

2. interference plate number of packages CN=solder joint layer number WL, then search and interfere the maximum common node of plate, under solder joint is divided it;

3. interference plate number of packages CN> solder joint layer number WL and CN-WL>WL, then to set up C _cn ^wlgroup comprises WL plate array, carries out asking for of maximum common node, and then can generate C _cn ^wlgroup node group, and in this node group, ask for the maximum node of number of levels, under this solder joint is divided to its node.

4. other situations do not divide.

The result exported is under all solder joints are mounted to corresponding assembling node with part form.