| 摘要 |
PURPOSE:To measure the stretching distance of a sheet like rubber test piece in its biaxial direction within its uniform deformation region, by measuring the intervals of chucks for grasping four sides of said test piece through reflective tapes adhered thereto by an image sensor. CONSTITUTION:The stretching distances of the section between P and Q and the section between p and R in a region PQRS to be measured in the vicinity of the center of a sheet like thin rubber test piece 10 being its uniform deformation region are measured and stretching ratios thereto are calculated from the measured values. In this case, reflective tapes A, B and C, D are adhered to each two chucks 12 of both ends in the direction of an axis X. When the cross point of the extension of the section PQ and the section between A and B, that is, the middle point (o) of the section AB is set (i) and the middle point of a section CD is similarily set to (j), the stretching of the section ij is read by an image sensor. The uniform deformation region is a region where the relation of Pij=Fij is formed with respect to the direction of the axis X. Pij is force acting on the section PQ and Fij is force acting on the section ij. The stretching of the section ij is calculated by measuring the displacement the reflective tapes A, B and C, D. |
