| 摘要 |
PURPOSE:To display marks of optional uniform size through simple constitution without trouble by forming a concave-shaped disk of spring wires between both expansible side plates, and expanding and contracting the side plates and varying the dismeter of the disk. CONSTITUTION:The spring wires 7 and 7' are fitted between the expansible side plates 1 and 2 and their vertical-angle part is made into a spring 8; and this part is coated with an elastic material member 10 such as a rubber thin piece to form the concave-shaped disk 5 and a projection 11 is provided on the circumference. When a butterfly nut 14 is rotated forward and backward, the diameter of the disk 5 varies. This variation in diameter is read on a scale bar 13 and after a desired diameter is obtained, this device is rolled on a body to be measured to obtain marks of the projection colored with a color pot 12 at equal intervals. Consequently, the marks of optional uniform size are displayed through the simple constitution without trouble and this is utilized effectively for construction work, etc. |
