Study On The Method Of Dimension Measurement Of Automobile Large Plastic Parts

At present, there are varieties of plastic parts that have been produced in manufacturing industry, especially plastic parts used in automobile, which has not only the large size but also the complex three-dimensional structure, is difficult and time-consuming to be measured by the conventional measurement tools (such as caliper, feeler, three coordinate measuring instrument, etc.), and the accurate results are difficult to be got too. All this directly affects the quality of the products, so as to bring great resistance to enterprise production and management.For all this, the systematic study on the detection method for automobile large plastic parts is made in this paper, involving the introduction of the checking fixture application and the use of statistical tools-MSA (Measurement Systems Analysis) to proceed a detailed analysis for checking fixture’s measurement system. In the process of the entire study, the checking fixture design principles are summarized, the checking fixture manufacture steps and acceptance criteria are formulated, the selecting method of the measurement points to large automobile plastic parts is determined. When using checking fixture to actually measure, the preparation and measurement methods are listed, the computer software is used to evaluate the repeatability and reproducibility, as for the standard of criterion according to the repeatability and reproducibility, combining with work experience, the checking fixture’s measuring method is improved. At last, the improvement effect through the tests is confirmed, an optimal measuring tool and method can be concluded.The research results can upgrade the company’s level of the detection for automobile large plastic parts, the automobile large plastic molding parts can meet the various production requirements.