双侧和单侧电子引伸计的比较

分析和比较了单侧和双侧电子引伸仪测量原理及测量误差。指出，国内外使用的电子引伸计多数是测量拉伸试样单侧的变形，由于拉伸试样往往发生偏心拉伸，单侧测量的引伸计无法扣除偏心拉伸的影响，因而其测量结果极不稳定和产生比较大的误差。而设计的双侧电子引伸计，只用两个刀刃能测得试样的对称双侧变形的平均值，这样扣除了弯曲变形的影响而得到了纯粹拉伸伸长。

THE COMPARISION OF TWO-SIDE AND ONE-SIDE ELECTRONIC EXTENSOMETER

The one-side electronic extensometer fastened on only one side of tensile specimen cannot eliminate the effect of bend of eccentric tension. The results of measurement of such electronic extensometer are instable and then more errors may be included. The first writer of this paper designs the two-slde electronic extensometer, which also has two edges but it can be fastened on two symmetric sides of the tensile specimen. As a result, it can eliminate the effect of bend of eccentric tension and measures the pure tensile elongation of specimen. In this paper the error in application with the one-side electronic extensometer is revealed, and a simple figure of the two-side electronic extensometer is provided and a proof of measurement principle of the two-side electronic extensometer is given with mechanics mechanism.