关键词：小型化 实验装置 弯扭组合 应变
Small portfolio deformation test-bed design and experimental research
Abstract
As to technical increasing development. Every country is also increasing emphasis on education and the investment in education is also increasing. the requirements to experimental equipment like Small size、Intelligent, simple, functional and economy is becoming more and more strict. However , compared with developed country, our country is relatively backwards in terms of Laboratory equipment because China's equipment has shortcomings of single function、huge size and not economic. This brings great impact on education. Thus the transformation and re-design of the experimental equipment will greatly enhance China's education level, bring very good results, and can save a lot for the state education fund.
Currently the shortcomings of the Combination of bending and torsion experimental device are as follows:
1. Too large volume. An experimental device needs to take up a test-bed size.
2. Complex Loading institutions, requested large load. Loading institutions are composed with hand wheel spin、weight and so on. The general load is 100 ～1000N, which also contributed to this large volume of devices.
3. Big experimental error. unreasonable designed experimental device 、unreasonable rosette location of the patch and unreasonable way of patch can cause big experimental error.
4. High cost of equipment is not conducive to expansion sets.
5. Single function. Incapable of dealing with a series of experiments. Our country’s teaching laboratory equipment exist so many shortcomings, Improving and re-designing equipment has great significance to education. That’s why this subject is choosed.
The improved design of small experimental combination of this subject has the following main features:
1. Low investment, convenient take up less space, facilitate the expansion sets
2. Easy to operate, low-fault, safety, and high accuracy because they are based on experimental teaching needs.
3. Each student could have one, help students complete an experiment independently. And also can verify theory by the comparison of Single-bending, single-twisting, bending and twisting combination and reverse shear elastic modulus G. providing simple and practical ways to experimental teaching as well as improving the quality of teaching.
In this paper, shortcomings of Old-fashioned combination of bending and torsion test equipment are raised through analysis of our country’s situation and program design. The theoretical basis and design principles of ultra-small experimental device combination of bending and torsion are established by measuring point state of stress and strain. An ultra-small experimental device combination of bending and torsion is designed with the feature of small volume、simple to load reasonable size of the structure and high accuracy.
Key words: miniaturization experimental device combined bending with torsion
