| 摘要 |
<p>PROBLEM TO BE SOLVED: To facilitate ascending of a staircase by setting height of a rise low as it goes upstairs and setting length of a tread short as it goes upstairs. SOLUTION: The height of the rise of a staircase 1 is formed low as it goes from the bottom height of the rise 2A through the second height of the rise 2B, the third height of the rise 2C... to the head height of the rise 2N. Furthermore, as the heights of the rise 2A, 2B, 2C...2N of the staircase 1 go upstairs, they are set gradually low, and as the lengths of 3A, 3B, 3C...2N go upstairs, they are set gradually short. The heights of the rise and the lengths of the effective widths of a tread are made same up to the intermediate part of the staircase 1, the heights of the rise from the intermediate part to the head part are formed low, and the lengths of the effective widths of the tread and formed short. Thus, fatigue burden can be relieved at the time of ascending of the staircase.</p> |
