| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide the tread fitting structure capable of securing a large contact area of a post and treads and being used for either of left-handed and right-handed going up and down. <P>SOLUTION: In this structure for fitting the post and treads of a spiral staircase, periphery of the wooden post 1 is formed by cutting with grooves 4, to which each of the treads respectively formed of two members is to be inserted in advance, and a hole 3 having the same dimension with the outer diameter of the groove cut in the post is bored in the tread in the condition that the two tread members 2a and 2b are combined together in advance. When assembling later, the tread formed of the two members can be fitted in the post from right and left to facilitate positioning and fitting of the post and the treads. The tread formed of the two members is formed into a bilateral symmetry shape to be used for any of right-handed and left-handed staircase. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
