| 摘要 |
PROBLEM TO BE SOLVED: To provide auxiliary handrails which can be stored while being accommodated in a manhole or locked on the manhole when closing the manhole, and can be detachably attached to an inner ladder when opening the manhole.SOLUTION: Auxiliary handrails 4, 4 are detachably attached to a manhole 1 having an inner ladder 3 constituted of two vertical materials 3a, 3a and a plurality of lateral materials 3b. In the auxiliary handrails 4, 4, flange lock members 4d at one-side ends of the auxiliary handrails 4, 4 are detachably attached to a flange 1b at an upper end of the manhole 1 with bolts 5, 5 in at least two points when opening the manhole 1, a grip part 4b at an upper part of the auxiliary handrail 4 is hung to the uppermost lateral material 3b of the inner ladder 3 when closing the manhole 1, thus accommodating the auxiliary handrails in the manhole 1, or the flange lock member 4d at one end side of the auxiliary handrail 4 is locked to an upper part of a lid 1c of the flange 1b with the bolts 5, 5 in at least two points, thus storing the auxiliary handrails.SELECTED DRAWING: Figure 3 |
