Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Unified modeling method of mechanical product tolerance

A modeling method and technology for mechanical products, applied in special data processing applications, instruments, electrical and digital data processing, etc., can solve the problems of modeling, unable to establish dimensional tolerance, shape tolerance unified model, etc., to eliminate diversity and two. Meaningful, easy-to-build effects

Inactive Publication Date: 2008-09-24
NORTHWESTERN POLYTECHNICAL UNIV
View PDF0 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The current tolerance modeling methods are: 1) CSG-based method; 2) B_rep-based method; 3) B_rep / CSG-based method; 4) variable geometry method; 5) TTRS-based (Topologically and Technologically Related Surface, and technology, Topologically related surfaces) methods, these methods are mainly aimed at the computer representation of geometric shapes and dimensional changes, without modeling the datum and direction of changes of geometric shapes and dimensional changes, and cannot establish tolerances including dimensional tolerances, shape tolerances, position tolerances and assembly Unified Model for Fitting Tolerances

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Unified modeling method of mechanical product tolerance
  • Unified modeling method of mechanical product tolerance
  • Unified modeling method of mechanical product tolerance

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0030] The present invention will be further described now in conjunction with accompanying drawing:

[0031] Take a component of an aircraft (see Figure 5 ) as an example for case analysis. The steps to establish the unified tolerance model of this component by adopting the unified modeling method of mechanical product tolerance of this patent are as follows:

[0032] The first step is to establish a part tolerance meta-model:

[0033] The part tolerance element model established by the extended directed graph is: G(KF, E, T, BT, V), where KF represents a set composed of n key features: KF={kf 1 , kf 2 ,..., kf n}, kf 1 , kf 2 ,..., kf n Represents n key features of parts, which are derived from basic features related to tolerances—points, lines, and surfaces; E represents a set of m tolerance relations connecting n key features: E={e i，j |i,j=1,2,...,n}, e i，j Indicates the key feature kf i , kf j The tolerance relationship between; T indicates the tolerance typ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a tolerance unified modeling method for a mechanical product, which adopts technologies of graph theory, vectors and characteristics, etc., and implements part tolerance element modeling, part tolerance modeling, assembly fit tolerance modeling and assembly body tolerance modeling layer by layer from bottom to top according to an assembly decomposition structure of the product, thereby realizing the unified modeling of product tolerances. The tolerance unified modeling method of the invention is characterized in that: the part tolerance element model is firstly established; each part tolerance element modeling built by extended directed graphs is adopted, and all the part tolerance element modeling are adopted to establish the part tolerance element models by a summation operation of the extended directed graphs; and each assembly fit tolerance modeling built by the extended directed graphs is adopted to establish a produc tolerance unified modeling. The tolerance unified modeling method for the mechanical product has the advantages of realizing the unified modeling of a dimension tolerance, a shape tolerance, a position tolerance and an assembly matching tolerance of the mechanical product. First, the diversity and the ambiguity of the tolerance models are eliminated; second, an assembly dimension chain and error accumulation analysis can be established conveniently.

Description

technical field [0001] The invention relates to a unified modeling method for mechanical product tolerances, which is used for establishing digital representations of mechanical product tolerances and belongs to the field of mechanical tolerance digitization. Background technique [0002] Tolerance refers to the precision characteristics used to describe the datum, direction of change and amount of change of geometric shape and size; tolerance modeling refers to the computer representation model describing the datum, direction of change and amount of change of geometric shape and size. The information is complete, valid, compatible, computable, etc. The current tolerance modeling methods are: 1) CSG-based method; 2) B_rep-based method; 3) B_rep / CSG-based method; 4) variable geometry method; 5) TTRS-based (Topologically and Technologically Related Surface, and technology, Topologically related surfaces) methods, these methods are mainly aimed at the computer representation o...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G06F17/50
Inventor 张开富李原
Owner NORTHWESTERN POLYTECHNICAL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com