CN116956485A - Screw column structure optimization design method based on CATIA software - Google Patents

Abstract

The application discloses a design method for optimizing stud modeling based on CATIA software, which integrates stud models of various types in one UDF module, and can realize the adaptation of 64 stud digital models by applying custom parameters when one UDF module is called, so that the risk of wrong allocation before stud model instantiation is avoided, corresponding parameter editing can be made along with modeling change after instantiation, the repeated calling of the model to adapt to a target environment can be avoided, and the modeling period is effectively shortened; technical requirements of enterprise design specifications are embedded in the UDF model, and prompt and optimization information is given for parameters which do not meet the requirements in the modeling process, so that the quantitative manufacturing feasibility can be effectively improved, and the project development cost is saved.

Description

Screw column structure optimization design method based on CATIA software

Technical Field

The application relates to a design method for modeling a plastic stud, in particular to an optimization design method based on CATIA software, and belongs to the technical field of CAD design of automobile parts.

Background

With the rapid development of domestic automobile industry, especially new energy automobiles, the requirements of comfortable, flexible and personalized clients are quite different, the functional complexity of the vehicle interior system is also increasingly improved, the market competition is globalized, the development period is continuously shortened, frequent vehicle type iteration and innovative modeling and process application are realized, and the development of the interior system is caused to face great challenges in efficiency.

Most of the part base materials of the automotive interior system are plastic products, and the parts base materials have better detachability, stability and lower use cost due to the fixed connection mode between the screw and the plastic stud, so that the automotive interior system is widely applied to the assembly of interior parts.

In the CAD conceptual design stage, the interior decoration system has great workload of digital-analog correction under a complex stud modeling environment because of great modeling change and frequent change. Therefore, the modeling efficiency of the stud is improved, the design specification is compatible with the design which is invalid in error prevention, and the development progress is very necessary to be rapidly advanced.

Among conventional modeling methods, there are generally the following 2 methods:

(1) Under the constructed local coordinate system, drawing a corresponding plan by utilizing a sketch function according to modeling and injection molding process requirements of an actual application area, and then constructing a 3D model on the basis. This approach requires redrawing the modeling at each point location, is inefficient, and has difficulty in ensuring consistency of the feature parameters.

(2) And constructing a local coordinate system at each point, and allocating a preset stud structure model (shown in figures 1a, 1b, 1c and 1 d) according to the modeling and injection molding process requirements of an actual application area to finish corresponding modeling requirements. The probability of the adaptation errors is high due to various types (table 1) when the model is called, parameters cannot be edited after the model is called, and when the model is subjected to multiple changes, repeated secondary design is needed to correct structural features, so that the efficiency is low.

TABLE 1 stud type

Disclosure of Invention

The application aims to solve the problem of providing a design method which can integrate stud models with various specifications, can adapt to various modeling application environments, and gives error reporting information and optimization suggestions aiming at parameters which do not meet the injection molding process and stud design specifications so as to realize the optimization stud structural modeling.

In view of the above, the technical scheme of the application is to provide a design method for optimizing stud modeling based on CATIA software, which comprises the following steps:

step 1, respectively constructing a stud seating point position, a stud demolding direction, an oblique top movement direction of the shrink-proof structure and a rib positioning direction to establish a coordinate system;

step 2: selecting a stud which is matched with the screw type;

step 3: calling and instantiating a stud model in a CATIA software Part Design application module;

step 4: according to the modeling environment, stud model parameters are customized, and the adaptive stud type, stud material type or size parameters for adjusting various structural characteristics can be selected from parameters issued by the instantiation model;

step 5: determining whether the stud needs the shrink prevention function, if so, checking the height dimension H of the shrink prevention platform, if the height H is larger than or equal to a set target value, turning to a step 6, otherwise, giving error prevention information, prompting to optimize the height parameter of the shrink prevention platform until the requirement is met;

step 6: checking the height dimension h of the screw column, if h is smaller than the set target value, turning to the step 7, otherwise, giving error-proofing information, and prompting to optimize the height parameter of the screw column until the requirement is met;

step 7: checking the effective screwing length L of the screw, if L is more than or equal to 2 times of the outer diameter d1 of the adaptive screw, turning to the step 8, otherwise, giving error-proofing information, prompting optimization of the screw height parameter until the requirement is met;

step 8: adjusting the angle of the positioning direction of the rib position according to the modeling environment;

step 9: and (5) ending.

Compared with the existing modeling method, the stud modeling optimization design method based on CATIA software has the following beneficial effects:

(1) Integrating multiple types of stud models into one UDF module, when one UDF module is called, the adaptation of 64 stud digital models (adapting 4 screws) can be realized by applying custom parameters (taking one type of adapting screw as an example, the corresponding stud type is shown in table 1), so that the risk of wrong allocation before the stud model is instantiated is avoided, corresponding parameter editing can be made along with modeling change after the stud model is instantiated, the situation that the model is called for multiple times to adapt to a target environment is avoided, and the modeling period is effectively shortened;

(2) Technical requirements of enterprise design specifications are embedded in the UDF model, and prompt and optimization information is given for parameters which do not meet the requirements in the modeling process, so that the quantitative manufacturing feasibility can be effectively improved, and the project development cost is saved.

These features and advantages of the present application will be disclosed in detail in the following detailed description and the accompanying drawings.

Drawings

The application is further described with reference to the accompanying drawings:

FIGS. 1a, 1b, 1c, 1d are schematic structural diagrams of studs;

FIG. 2 is a schematic diagram of a stud setup coordinate system;

FIG. 3 is a schematic illustration of stud size;

FIGS. 4a, 4b, 4c are diagrams illustrating variations in stud size;

FIG. 5 screw & stud assembly schematic;

FIG. 6 is a flow chart of a CATIA software stud modeling optimization design method;

FIG. 7 is a stud placement effect diagram.

Detailed Description

The technical solutions of the embodiments of the present application will be explained and illustrated below with reference to the drawings of the embodiments of the present application, but the following embodiments are only preferred embodiments of the present application, and not all embodiments. Based on the examples in the implementation manner, other examples obtained by a person skilled in the art without making creative efforts fall within the protection scope of the present application.

Before describing the embodiments in detail, some descriptions are first made of variable parameters of a 3D model of a stud, which may be divided into type variables and dimension variables.

Type variable: as shown in table 1, under the condition of adapting screw threads of the same specification (screw thread specification is according to GB/T5280-2002,I SO 1478:1999), the stud structure model can screen an adapted target type from the combination of 4 types of variables of "material type", "specification type", "shrink-proof function" and "positioning function", the stud model can adapt to multiple screw threads, and each screw thread has 16 combination results;

the dimension variable (shown in figures 4a, 4B and 4 c) is that a is the length dimension of the anti-shrinkage table, B is the width dimension of the anti-shrinkage table, c is the height dimension of the anti-shrinkage table, d is the height dimension of the anti-shrinkage section of the anti-shrinkage table, E is the distance dimension of a positioning column, A is the demoulding angle of the anti-shrinkage table in the main demoulding direction, B is the demoulding angle of the anti-shrinkage table in the oblique jacking stroke direction, E is the locating direction angle of the rib position, and N is the number of the supporting rib positions;

the demoulding angle of the shrink prevention table in the main demoulding direction is B, namely the demoulding angle of the shrink prevention table in the oblique jacking travel direction, E, namely the rib position positioning direction angle, and N, namely the number of supporting rib positions;

the variable parameters can be adjusted before and after the stud model is assembled and adjusted;

the following are specific implementation steps of the embodiment:

the first step: constructing a target point for placing the stud structure at a CATIA Part Design module, wherein the point is an intersection point of the top surface of the stud and the axis of the stud, a coordinate vector value under a vehicle body coordinate system is used for driving a position, the point is used as an origin, and a demoulding direction is used as the axis for creating a stud coordinate system; respectively constructing a stud seating point j, a stud demolding direction p, an oblique top movement direction q of the shrink-proof structure and a rib positioning direction k to establish a coordinate system;

and a second step of: corresponding stud models are selected according to the specification of the adapting thread, and the common screw models are ST4.2, ST3.5, PT4.0 and PT3.0, and the stud model adapting to the ST4.2 screw is selected in the embodiment;

and a third step of: matching corresponding point positions and axis elements at a CATIA Part Design module, and instantiating an ST4.2 stud model;

fourth step: according to the target use environment, adjusting type variable parameters to adapt to related part design specifications, wherein the types of materials are selected from PP types and ABS types, the sleeved type and the non-sleeved type are selected according to the screw screwing length space in the axis direction of the stud, and whether a positioning column structure is added is selected according to positioning requirements;

fifth step: according to the target use environment, selecting an anti-shrink table structure, setting an adjustable dimension variable c (shown in fig. 4a, 4b and 4 c) when the anti-shrink table is arranged so as to ensure that H is more than or equal to 4mm (set target value of an enterprise, shown in fig. 3), prompting error information if the limit value interval is exceeded, enabling engineers to pertinently optimize the value c according to the information until the requirement is met, and directly transferring to a sixth step if the anti-shrink table structure is not selected;

sixth step: according to the length of the matched screw, optimizing the height dimension h (figure 3) of the screw column, adjusting the value c (figures 4a, 4b and 4 c) to ensure that h is less than or equal to 25mm (enterprise set target value, figure 3), if the limit value interval is exceeded, prompting error information, and enabling engineers to pertinently optimize the value c according to the information until the requirement is met;

seventh step: according to the matching thread specification ST4.2, optimizing the effective screwing length L (figure 5) of the screw to ensure that L is less than 2d1 (enterprise set target value, figure 5), if the limit value interval is exceeded, prompting error reporting information, and enabling engineers to pertinently adjust the value c (figures 4a, 4b and 4 c) or the axial direction vector value of the stud seating point according to the information until the requirements are met (figure 2);

eighth step: optimizing the demoulding angle A of the main demoulding direction of the shrink prevention platform according to the use environment of the target,

the demoulding angle B in the oblique top stroke direction of the shrink prevention table, the rib position layout angle E and the number N of supporting rib positions;

ninth step: and (3) finishing stud model parameter optimization, and completing stud structural design of the target part by using Boolean operation (figure 6).

After the stud model is imported by the scheme, the stud position can be driven and edited by the vector value of the stud seating point, the stud model can be adjusted in batches by CATIA knowledge engineering array commands (figure 7), and then the type variable parameters and the size variable parameters are edited to adapt to the target environment area, so that the design efficiency can be remarkably improved compared with the traditional manual modeling mode.

The above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims (1)

1. The design method for optimizing stud modeling based on CATIA software is characterized by comprising the following steps:

step 1, respectively constructing a stud seating point position, a stud demolding direction, an oblique top movement direction of the shrink-proof structure and a rib positioning direction to establish a coordinate system;

step 2: selecting a stud which is matched with the screw type;

step 3: calling and instantiating a stud model in a CATIA software PartDesign application module;

step 4: according to the modeling environment, stud model parameters are customized, and the adaptive stud type, stud material type or size parameters for adjusting various structural characteristics can be selected from parameters issued by the instantiation model;

step 5: determining whether the stud needs the shrink prevention function, if so, checking the height dimension H of the shrink prevention platform, if the height H is larger than or equal to a set target value, turning to a step 6, otherwise, giving error prevention information, prompting to optimize the height parameter of the shrink prevention platform until the requirement is met;

step 6: checking the height dimension h of the screw column, if h is smaller than the set target value, turning to the step 7, otherwise, giving error-proofing information, and prompting to optimize the height parameter of the screw column until the requirement is met;

step 7: checking the effective screwing length L of the screw, if L is more than or equal to 2 times of the outer diameter d1 of the adaptive screw, turning to the step 8, otherwise, giving error-proofing information, prompting optimization of the screw height parameter until the requirement is met;

step 8: adjusting the angle of the positioning direction of the rib position according to the modeling environment;

step 9: and (5) ending.